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Dhimba G, Muller A, Lammertsma K. Chiral-at-Metal Racemization Unraveled for MX 2 (a-chel) 2 by means of a Computational Analysis of MoO 2 (acnac) 2. Chemistry 2023; 29:e202302516. [PMID: 37730887 DOI: 10.1002/chem.202302516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 09/13/2023] [Accepted: 09/14/2023] [Indexed: 09/22/2023]
Abstract
Octahedral chiral-at-metal complexes MX2 (a-chel)2 (a-chel=asymmetric chelate) can rearrange their ligands by four mechanisms known as the Bailar (B), Ray-Dutt (RD), Conte-Hippler (CH), and Dhimba-Muller-Lammertsma (DML) twists. Racemization involves their interconnections, which were computed for MoO2 (acnac)2 (acnac=β-ketoiminate) using density functional theory at ωB97x-D with the 6-31G(d,p) and 6-311G(2d,p) basis sets and LANL2DZ for molybdenum. Racemizing the cis(NN) isomer, being the global energy minimum with trans oriented imine groups, is a three step process (DML-CH-DML) that requires 17.4 kcal/mol, while all three cis isomers (cis(NN), cis(NO), and cis(OO)) interconvert at ≤17.9 kcal/mol. The B and RD twists are energetically not competitive and neither are the trans isomers. The interconnection of all enantiomeric minima and transition structures is summarized in a graph that also visualizes valley ridge inflection points for two of the three CH twists. Geometrical features of the minima and twists are given. Lastly, the influence of N-substitution on the favored racemization pathway is evaluated. The present comprehensive study serves as a template for designing chiral-at-metal MX2 (a-chel)2 catalysts that may retain their chiral integrity.
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Affiliation(s)
- George Dhimba
- Department of Chemical Sciences, University of Johannesburg, Auckland Park, Johannesburg, 2006, South Africa
| | - Alfred Muller
- Department of Chemical Sciences, University of Johannesburg, Auckland Park, Johannesburg, 2006, South Africa
| | - Koop Lammertsma
- Department of Chemical Sciences, University of Johannesburg, Auckland Park, Johannesburg, 2006, South Africa
- Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ, Amsterdam, The Netherlands
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Vlasyuk D, Łyszczek R, Mazur L, Pladzyk A, Hnatejko Z, Woźny P. A Series of Novel 3D Coordination Polymers Based on the Quinoline-2,4-dicarboxylate Building Block and Lanthanide(III) Ions-Temperature Dependence Investigations. Molecules 2023; 28:6360. [PMID: 37687189 PMCID: PMC10489008 DOI: 10.3390/molecules28176360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/21/2023] [Accepted: 08/24/2023] [Indexed: 09/10/2023] Open
Abstract
A series of novel 3D coordination polymers [Ln2(Qdca)3(H2O)x]·yH2O (x = 3 or 4, y = 0-4) assembled from selected lanthanide ions (Ln(III) = Nd, Eu, Tb, and Er) and a non-explored quinoline-2,4-dicarboxylate building block (Qdca2- = C11H5NO42-) were prepared under hydrothermal conditions at temperatures of 100, 120, and 150 °C. Generally, an increase in synthesis temperature resulted in structural transformations and the formation of more hydrated compounds. The metal complexes were characterized by elemental analysis, single-crystal and powder X-ray diffraction methods, thermal analysis (TG-DSC), ATR/FTIR, UV/Vis, and luminescence spectroscopy. The structural variety of three-dimensional coordination polymers can be ascribed to the temperature effect, which enforces the diversity of quinoline-2,4-dicarboxylate ligand denticity and conformation. The Qdca2- ligand only behaves as a bridging or bridging-chelating building block binding two to five metal centers with seven different coordination modes arising mainly from different carboxylate group coordination types. The presence of water molecules in the structures of complexes is crucial for their stability. The removal of both coordinated and non-coordinated water molecules leads to the disintegration and combustion of metal-organic frameworks to the appropriate lanthanide oxides. The luminescence features of complexes, quantum yield, and luminescent lifetimes were measured and analyzed. Only the Eu complexes show emission in the VIS region, whereas Nd and Er complexes emit in the NIR range. The luminescence properties of complexes were correlated with the crystal structures of the investigated complexes.
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Affiliation(s)
- Dmytro Vlasyuk
- Department of General and Coordination Chemistry and Crystallography, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Skłodowska University, M. C. Skłodowskiej Sq. 2, 20-031 Lublin, Poland;
| | - Renata Łyszczek
- Department of General and Coordination Chemistry and Crystallography, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Skłodowska University, M. C. Skłodowskiej Sq. 2, 20-031 Lublin, Poland;
| | - Liliana Mazur
- Department of General and Coordination Chemistry and Crystallography, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Skłodowska University, M. C. Skłodowskiej Sq. 2, 20-031 Lublin, Poland;
| | - Agnieszka Pladzyk
- Department of Inorganic Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Zbigniew Hnatejko
- Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland; (Z.H.); (P.W.)
| | - Przemysław Woźny
- Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland; (Z.H.); (P.W.)
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Sockwell AK, Sweet TFM, Barth B, Isbill SB, DiBlasi NA, Szymanowski JES, Sigmon GE, Oliver AG, Miskowiec AJ, Burns PC, Hixon AE. Insight into the Structural Ambiguity of Actinide(IV) Oxalate Sheet Structures: A Case for Alternate Coordination Geometries. Chemistry 2023; 29:e202301164. [PMID: 37227412 DOI: 10.1002/chem.202301164] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 05/18/2023] [Accepted: 05/24/2023] [Indexed: 05/26/2023]
Abstract
Plutonium(IV) oxalate hexahydrate (Pu(C2 O4 )2 ⋅ 6 H2 O; PuOx) is an important intermediate in the recovery of plutonium from used nuclear fuel. Its formation by precipitation is well studied, yet its crystal structure remains unknown. Instead, the crystal structure of PuOx is assumed to be isostructural with neptunium(IV) oxalate hexahydrate (Np(C2 O4 )2 ⋅ 6 H2 O; NpOx) and uranium(IV) oxalate hexahydrate (U(C2 O4 )2 ⋅ 6 H2 O; UOx) despite the high degree of unresolved disorder that exists when determining water positions in the crystal structures of the latter two compounds. Such assumptions regarding the isostructural behavior of the actinide elements have been used to predict the structure of PuOx for use in a wide range of studies. Herein, we report the first crystal structures for PuOx and Th(C2 O4 )2 ⋅ 6 H2 O (ThOx). These data, along with new characterization of UOx and NpOx, have resulted in the full determination of the structures and resolution of the disorder around the water molecules. Specifically, we have identified the coordination of two water molecules with each metal center, which necessitates a change in oxalate coordination mode from axial to equatorial that has not been reported in the literature. The results of this work exemplify the need to revisit previous assumptions regarding fundamental actinide chemistry, which are heavily relied upon within the current nuclear field.
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Affiliation(s)
- A Kirstin Sockwell
- Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana, 46556, USA
| | - Teagan F M Sweet
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Brodie Barth
- Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana, 46556, USA
| | - Sara B Isbill
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Nicole A DiBlasi
- Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana, 46556, USA
- Current address: Actinide Analytical Chemistry, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Jennifer E S Szymanowski
- Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana, 46556, USA
| | - Ginger E Sigmon
- Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana, 46556, USA
| | - Allen G Oliver
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | | | - Peter C Burns
- Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana, 46556, USA
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Amy E Hixon
- Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana, 46556, USA
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Buyens DMS, Pilcher LA, Cukrowski I. Coordination Sites for Sodium and Potassium Ions in Nucleophilic Adeninate Contact ion-Pairs: A Molecular-Wide and Electron Density-Based (MOWED) Perspective. Molecules 2022; 27:molecules27186111. [PMID: 36144844 PMCID: PMC9505275 DOI: 10.3390/molecules27186111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 11/16/2022]
Abstract
The adeninate anion (Ade-) is a useful nucleophile used in the synthesis of many prodrugs (including those for HIV AIDS treatment). It exists as a contact ion-pair (CIP) with Na+ and K+ (M+) but the site of coordination is not obvious from spectroscopic data. Herein, a molecular-wide and electron density-based (MOWED) computational approach implemented in the implicit solvation model showed a strong preference for bidentate ion coordination at the N3 and N9 atoms. The N3N9-CIP has (i) the strongest inter-ionic interaction, by -30 kcal mol-1, with a significant (10-15%) covalent contribution, (ii) the most stabilized bonding framework for Ade-, and (iii) displays the largest ion-induced polarization of Ade-, rendering the N3 and N9 the most negative and, hence, most nucleophilic atoms. Alkylation of the adeninate anion at these two positions can therefore be readily explained when the metal coordinated complex is considered as the nucleophile. The addition of explicit DMSO solvent molecules did not change the trend in most nucleophilic N-atoms of Ade- for the in-plane M-Ade complexes in M-Ade-(DMSO)4 molecular systems. MOWED-based studies of the strength and nature of interactions between DMSO solvent molecules and counter ions and Ade- revealed an interesting and unexpected chemistry of intermolecular chemical bonding.
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Piesch M, Nicolay A, Haimerl M, Seidl M, Balázs G, Don Tilley T, Scheer M. Binding, Release and Functionalization of Intact Pnictogen Tetrahedra Coordinated to Dicopper Complexes. Chemistry 2022; 28:e202201144. [PMID: 35575052 PMCID: PMC9541576 DOI: 10.1002/chem.202201144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Indexed: 01/07/2023]
Abstract
The bridging MeCN ligand in the dicopper(I) complexes [(DPFN)Cu2(μ,η1 : η1‐MeCN)][X]2 (X=weakly coordinating anion, NTf2 (1 a), FAl[OC6F10(C6F5)]3 (1 b), Al[OC(CF3)3]4 (1 c)) was replaced by white phosphorus (P4) or yellow arsenic (As4) to yield [(DPFN)Cu2(μ,η2 : η2‐E4)][X]2 (E=P (2 a–c), As (3 a–c)). The molecular structures in the solid state reveal novel coordination modes for E4 tetrahedra bonded to coinage metal ions. Experimental data and quantum chemical computations provide information concerning perturbations to the bonding in coordinated E4 tetrahedra. Reactions with N‐heterocyclic carbenes (NHCs) led to replacement of the E4 tetrahedra with release of P4 or As4 and formation of [(DPFN)Cu2(μ,η1 : η1‐MeNHC)][X]2 (4 a,b) or to an opening of one E−E bond leading to an unusual E4 butterfly structural motif in [(DPFN)Cu2(μ,η1 : η1‐E4DippNHC)][X]2 (E=P (5 a,b), E=As (6)). With a cyclic alkyl amino carbene (EtCAAC), cleavage of two As−As bonds was observed to give two isomers of [(DPFN)Cu2(μ,η2 : η2‐As4EtCAAC)][X]2 (7 a,b) with an unusual As4‐triangle+1 unit.
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Affiliation(s)
- Martin Piesch
- Institute of Inorganic Chemistry, University of Regensburg, 93040, Regensburg, Germany
| | - Amélie Nicolay
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720-1460, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, 94720, United States
| | - Maria Haimerl
- Institute of Inorganic Chemistry, University of Regensburg, 93040, Regensburg, Germany
| | - Michael Seidl
- Institute of Inorganic Chemistry, University of Regensburg, 93040, Regensburg, Germany
| | - Gábor Balázs
- Institute of Inorganic Chemistry, University of Regensburg, 93040, Regensburg, Germany
| | - T Don Tilley
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720-1460, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, 94720, United States
| | - Manfred Scheer
- Institute of Inorganic Chemistry, University of Regensburg, 93040, Regensburg, Germany
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Canty AJ, Ariafard A, van Koten G. Computational Study of Bridge Splitting, Aryl Halide Oxidative Addition to Pt II , and Reductive Elimination from Pt IV : Route to Pincer-Pt II Reagents with Chemical and Biological Applications. Chemistry 2021; 27:15426-15433. [PMID: 34473849 DOI: 10.1002/chem.202102687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Indexed: 11/06/2022]
Abstract
Density functional theory computation indicates that bridge splitting of [PtII R2 (μ-SEt2 )]2 proceeds by partial dissociation to form R2 Pta (μ-SEt2 )Ptb R2 (SEt2 ), followed by coordination of N-donor bromoarenes (L-Br) at Pta leading to release of Ptb R2 (SEt2 ), which reacts with a second molecule of L-Br, providing two molecules of PtR2 (SEt2 )(L-Br-N). For R=4-tolyl (Tol), L-Br=2,6-(pzCH2 )2 C6 H3 Br (pz=pyrazol-1-yl) and 2,6-(Me2 NCH2 )2 C6 H3 Br, subsequent oxidative addition assisted by intramolecular N-donor coordination via PtII Tol2 (L-N,Br) and reductive elimination from PtIV intermediates gives mer-PtII (L-N,C,N)Br and Tol2 . The strong σ-donor influence of Tol groups results in subtle differences in oxidative addition mechanisms when compared with related aryl halide oxidative addition to palladium(II) centres. For R=Me and L-Br=2,6-(pzCH2 )2 C6 H3 Br, a stable PtIV product, fac-PtIV Me2 {2,6-(pzCH2 )2 C6 H3 -N,C,N)Br is predicted, as reported experimentally, acting as a model for undetected and unstable PtIV Tol2 {L-N,C,N}Br undergoing facile Tol2 reductive elimination. The mechanisms reported herein enable the synthesis of PtII pincer reagents with applications in materials and bio-organometallic chemistry.
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Affiliation(s)
- Allan J Canty
- School of Natural Sciences - Chemistry, University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia
| | - Alireza Ariafard
- School of Natural Sciences - Chemistry, University of Tasmania, Private Bag 75, Hobart, Tasmania, 7001, Australia
| | - Gerard van Koten
- Organic Chemistry and Catalysis, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584CG, Utrecht, The Netherlands
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Abstract
The seven-membered cyclic potassium alumanyl species, [{SiNMes }AlK]2 [{SiNMes }={CH2 SiMe2 N(Mes)}2 ; Mes=2,4,6-Me3 C6 H2 ], which adopts a dimeric structure supported by flanking K-aryl interactions, has been isolated either by direct reduction of the iodide precursor, [{SiNMes }AlI], or in a stepwise manner via the intermediate dialumane, [{SiNMes }Al]2 . Although the intermediate dialumane has not been observed by reduction of a Dipp-substituted analogue (Dipp=2,6-i-Pr2 C6 H3 ), partial oxidation of the potassium alumanyl species, [{SiNDipp }AlK]2 , where {SiNDipp }={CH2 SiMe2 N(Dipp)}2 , provided the extremely encumbered dialumane [{SiNDipp }Al]2 . [{SiNDipp }AlK]2 reacts with toluene by reductive activation of a methyl C(sp3 )-H bond to provide the benzyl hydridoaluminate, [{SiNDipp }AlH(CH2 Ph)]K, and as a nucleophile with BPh3 and RN=C=NR (R=i-Pr, Cy) to yield the respective Al-B- and Al-C-bonded potassium aluminaborate and alumina-amidinate products. The dimeric structure of [{SiNDipp }AlK]2 can be disrupted by partial or complete sequestration of potassium. Equimolar reactions with 18-crown-6 result in the corresponding monomeric potassium alumanyl, [{SiNDipp }Al-K(18-cr-6)], which provides a rare example of a direct Al-K contact. In contrast, complete encapsulation of the potassium cation of [{SiNDipp }AlK]2 , either by an excess of 18-cr-6 or 2,2,2-cryptand, allows the respective isolation of bright orange charge-separated species comprising the 'free' [{SiNDipp }Al]- alumanyl anion. Density functional theory (DFT) calculations performed on this moiety indicate HOMO-LUMO energy gaps in the of order 200-250 kJ mol-1 .
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Affiliation(s)
- Ryan J Schwamm
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
| | - Michael S Hill
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
| | - Han-Ying Liu
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
| | - Mary F Mahon
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
| | - Claire L McMullin
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
| | - Nasir A Rajabi
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
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Rong MK, Holtrop F, Bobylev EO, Nieger M, Ehlers AW, Slootweg JC, Lammertsma K. Atypical and Asymmetric 1,3-P,N Ligands: Synthesis, Coordination and Catalytic Performance of Cycloiminophosphanes. Chemistry 2021; 27:14007-14016. [PMID: 34403555 PMCID: PMC8519111 DOI: 10.1002/chem.202101921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Indexed: 11/22/2022]
Abstract
Novel seven-membered cyclic imine-based 1,3-P,N ligands were obtained by capturing a Beckmann nitrilium ion intermediate generated in situ from cyclohexanone with benzotriazole, and then displacing it by a secondary phosphane under triflic acid promotion. These "cycloiminophosphanes" possess flexible non-isomerizable tetrahydroazepine rings with a high basicity; this sets them apart from previously reported iminophophanes. The donor strength of the ligands was investigated by using their P-κ1 - and P,N-κ2 -tungsten(0) carbonyl complexes, by determining the IR frequency of the trans-CO ligands. Complexes with [RhCp*Cl2 ]2 demonstrated the hemilability of the ligands, giving a dynamic equilibrium of κ1 and κ2 species; treatment with AgOTf gives full conversion to the κ2 complex. The potential for catalysis was shown in the RuII -catalyzed, solvent-free hydration of benzonitrile and the RuII - and IrI -catalyzed transfer hydrogenation of cyclohexanone in isopropanol. Finally, to enable access to asymmetric catalysts, chiral cycloiminophosphanes were prepared from l-menthone, as well as their P,N-κ2 -RhIII and a P-κ1 -RuII complexes.
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Affiliation(s)
- Mark K. Rong
- Department of Chemistry and Pharmaceutical SciencesVrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
| | - Flip Holtrop
- Department of Chemistry and Pharmaceutical SciencesVrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
| | - Eduard O. Bobylev
- Department of Chemistry and Pharmaceutical SciencesVrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
| | - Martin Nieger
- Department of ChemistryUniversity of HelsinkiA. I. Virtasen aukio 1, P.O. Box 55FIN-00014HelsinkiFinland
| | - Andreas W. Ehlers
- Department of Chemistry and Pharmaceutical SciencesVrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
- Department of ChemistryUniversity of JohannesburgOakland Park2006JohannesburgSouth Africa
- Present address: Van 't Hoff Institute for Molecular SciencesUniversity of AmsterdamP.O. Box 941571090 GDAmsterdamThe Netherlands
| | - J. Chris Slootweg
- Department of Chemistry and Pharmaceutical SciencesVrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
- Present address: Van 't Hoff Institute for Molecular SciencesUniversity of AmsterdamP.O. Box 941571090 GDAmsterdamThe Netherlands
| | - Koop Lammertsma
- Department of Chemistry and Pharmaceutical SciencesVrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
- Department of ChemistryUniversity of JohannesburgOakland Park2006JohannesburgSouth Africa
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Teng X, Sheveleva A, Tuna F, Willison KR, Ying L. Acetylation Rather than H50Q Mutation Impacts the Kinetics of Cu(II) Binding to α-Synuclein. Chemphyschem 2021; 22:2413-2419. [PMID: 34617653 PMCID: PMC9293329 DOI: 10.1002/cphc.202100651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 10/02/2021] [Indexed: 11/10/2022]
Abstract
The interaction between α‐synuclein (αSyn) and Cu2+ has been suggested to be closely linked to brain copper homeostasis. Disruption of copper levels could induce misfolding and aggregation of αSyn, and thus contribute to the progression of Parkinson's disease (PD). Understanding the molecular mechanism of αSyn‐Cu2+ interaction is important and controversies in Cu2+ coordination geometry with αSyn still exists. Herein, we find that the pathological H50Q mutation has no impact on the kinetics of Cu2+ binding to the high‐affinity site of wild type αSyn (WT‐αSyn), indicating the non‐involvement of His50 in high‐affinity Cu2+ binding to WT‐αSyn. In contrast, the physiological N‐terminally acetylated αSyn (NAc‐αSyn) displays several orders of magnitude weaker Cu2+ binding affinity than WT‐αSyn. Cu2+ coordination mode to NAc‐αSyn has also been proposed based on EPR spectrum. In addition, we find that Cu2+ coordinated WT‐αSyn is reduction‐active in the presence of GSH, but essentially inactive towards ascorbate. Our work provides new insights into αSyn‐Cu2+ interaction, which may help understand the multifaceted normal functions of αSyn as well as pathological consequences of αSyn aggregation.
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Affiliation(s)
- Xiangyu Teng
- Department of Chemistry, Imperial College London, White City Campus, London, W12 0BZ, UK
| | - Alena Sheveleva
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Floriana Tuna
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Keith R Willison
- Department of Chemistry, Imperial College London, White City Campus, London, W12 0BZ, UK
| | - Liming Ying
- National Heart and Lung Institute, Imperial College London, White City Campus, London, W12 0BZ, UK
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Kumar V, Gonnade RG, Yildiz CB, Majumdar M. Stabilization of the Elusive Antimony(I) Cation and Its Coordination Complexes with Transition Metals. Angew Chem Int Ed Engl 2021; 60:25522-25529. [PMID: 34505340 DOI: 10.1002/anie.202111339] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Indexed: 12/16/2022]
Abstract
Upon stabilization by 5,6-bis(diisopropylphosphino)acenaphthene to form compound 1, the fugitive antimony (I) cation exhibited nucleophilic behavior towards coinage metals. Compound 1 was strategically synthesized at room temperature from SbCl3 , the bis(phosphine), and trimethylsilyl trifluoromethanesulfonate taken in a 1:2:3 ratio, whereby the bis(phosphine) plays the dual role of a reductant and a supporting ligand. The generation of 1 involves two-electron oxidation of the ligand to form a P-P bonded diphosphonium dication. Compound 1 was separated from this dication to give both products in pure form in moderate yields. Despite the overall positive charge, the SbI site in 1 was found to bind to metal centers, forming complexes with AuI , AgI and CuI . Compound 1 reduced CuII to CuI and formed a coordination complex with the resulting CuI species. The effects of the electron-rich bis(phosphine) and the constrained peri geometry in stabilizing and enhancing the nucleophilicity of 1 have been rationalized through computational studies.
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Affiliation(s)
- Vikas Kumar
- Department of Chemistry, Indian Institute of Science Education and Research, Pune, Dr. Homi Bhabha Road, Pashan, Pune, 411008, Maharashtra, India
| | - Rajesh G Gonnade
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune, 411008, Maharashtra, India
| | - Cem B Yildiz
- Department of Aromatic and Medicinal Plants, Aksaray University, 68100, Aksaray, Turkey
| | - Moumita Majumdar
- Department of Chemistry, Indian Institute of Science Education and Research, Pune, Dr. Homi Bhabha Road, Pashan, Pune, 411008, Maharashtra, India
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Zhang WX, Hao YN, Gao YR, Shu Y, Wang JH. Mutual Benefit between Cu(II) and Polydopamine for Improving Photothermal-Chemodynamic Therapy. ACS Appl Mater Interfaces 2021; 13:38127-38137. [PMID: 34347422 DOI: 10.1021/acsami.1c12199] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Combination therapy has attracted extensive interest in alleviating the shortcomings of monotherapy and enhancing the treatment efficacy. In this work, hollow mesoporous silica nanoparticles (HMSNs) play the role of nanocarriers in the delivery of Cu(II)-doped polydopamine (PDA), termed as HMSNs@PDA-Cu, for synergistic therapy. PDA acts as a traditional photothermal agent to realize photothermal treatment (PTT). Chemodynamic therapy (CDT) is realized by the reaction of Cu(II) with intracellular glutathione (GSH), and subsequently, the generated Cu(I) reacts with H2O2 to produce toxic hydroxyl radical (•OH) through a Fenton-like reaction. The photothermal performance of PDA is improved after its coordination with Cu(II). On the other hand, PDA exhibits superoxide dismutase (SOD)-mimicking activity. PDA converts O2•- to H2O2 and improves the production of H2O2, which promotes the therapeutic effect of CDT. Moreover, the high temperature caused by PTT further enhances the yield of •OH for CDT. This nanotheranostic platform perfectly applied to the tumor depletion of mice, presenting great potential for cancer metastasis therapy in vitro and in vivo.
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Affiliation(s)
- Wen-Xin Zhang
- Department of Chemistry, College of Sciences, Northeastern University, Box 332, Shenyang 110819, China
| | - Ya-Nan Hao
- Department of Chemistry, College of Sciences, Northeastern University, Box 332, Shenyang 110819, China
| | - Yi-Ru Gao
- Department of Chemistry, College of Sciences, Northeastern University, Box 332, Shenyang 110819, China
| | - Yang Shu
- Department of Chemistry, College of Sciences, Northeastern University, Box 332, Shenyang 110819, China
| | - Jian-Hua Wang
- Department of Chemistry, College of Sciences, Northeastern University, Box 332, Shenyang 110819, China
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12
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Cai X, Peng F, Luo X, Ye X, Zhou J, Lang X, Shi M. Understanding the Evolution of Cobalt-Based Metal-Organic Frameworks in Electrocatalysis for the Oxygen Evolution Reaction. ChemSusChem 2021; 14:3163-3173. [PMID: 34101996 DOI: 10.1002/cssc.202100851] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 06/03/2021] [Indexed: 06/12/2023]
Abstract
Metal-organic frameworks (MOFs) have attracted increasing attention as a promising electrode material for the oxygen evolution reaction (OER). Comprehending catalytic mechanisms in the OER process is of key relevance for the design of efficient catalysts. In this study, two types of Co based MOF with different organic ligands (ZIF-67 and CoBDC; BDC=1,4-benzenedicarboxylate) are synthesized as OER electrocatalysts and their electrochemical behavior is studied in alkaline solution. Physical characterization indicates that ZIF-67, with tetrahedral Co sites, transforms into α-Co(OH)2 on electrochemical activation, which provides continuous active sites in the following oxidation, whereas CoBDC, with octahedral sites, evolves into β-Co(OH)2 through hydrolysis, which is inert for the OER. Electrochemical characterization reveals that Co sites coordinated by nitrogen from imidazole ligands (Co-N coordination) are more inclined to electrochemical activation than Co-O sites. The successive exposure and accumulation of real active sites is responsible for the gradual increase in activity of ZIF-67 in OER. This work not only indicates that CoMOFs are promising OER electrocatalysts but also provides a reference system to understand how metal coordination in MOFs affects the OER process.
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Affiliation(s)
- Xiaowei Cai
- The State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310032, Zhejiang, P. R. China
| | - Fei Peng
- The State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310032, Zhejiang, P. R. China
| | - Xingyu Luo
- The State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310032, Zhejiang, P. R. China
| | - Xuejie Ye
- The State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310032, Zhejiang, P. R. China
| | - Junxi Zhou
- The State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310032, Zhejiang, P. R. China
| | - Xiaoling Lang
- Fujian Provincial Key Laboratory of Clean Energy Materials, Longyan, 364000, Fujian, P. R. China
| | - Meiqin Shi
- The State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310032, Zhejiang, P. R. China
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13
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Abstract
Homometallic titanium oxo clusters are one of the most important groups of metal oxo clusters, with more than 300 examples characterized by X-ray structure analyses. Most of them are uncharged and are obtained by partial hydrolysis and condensation of titanium alkoxo derivatives. The cluster cores, ranging from 3 to >50 titanium atoms, are stabilized by organic ligands. Apart from residual OR groups, carboxylato and phosphonato ligands are most frequent. The article critically reviews and categorizes the known structures and works out basic construction principles by comparing the different cluster types.
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Affiliation(s)
- Ulrich Schubert
- Institute of Materials ChemistryTechnische Universität WienGetreidemarkt 91060WienAustria
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14
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Zhang L, Lin YJ, Li ZH, Fraser Stoddart J, Jin GX. Coordination-Driven Selective Formation of D 2 Symmetric Octanuclear Organometallic Cages. Chemistry 2021; 27:9524-9528. [PMID: 33882176 DOI: 10.1002/chem.202101204] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Indexed: 11/09/2022]
Abstract
The coordination-driven self-assembly of organometallic half-sandwich iridium(III)- and rhodium(III)-based building blocks with asymmetric ambidentate pyridyl-carboxylate ligands is described. Despite the potential for obtaining a statistical mixture of multiple products, D2 symmetric octanuclear cages were formed selectively by taking advantage of the electronic effects emanating from the two types of chelating sites - (O,O') and (N,N') - on the tetranuclear building blocks. The metal sources and the lengths of bridging ligands influence the selectivity of the self-assembly. Experimental observations, supported by computational studies, suggest that the D2 symmetric cages are the thermodynamically favored products. Overall, the results underline the importance of electronic effects on the selectivity of coordination-driven self-assembly, and demonstrate that asymmetric ambidentate ligands can be used to control the design of discrete supramolecular coordination complexes.
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Affiliation(s)
- Long Zhang
- State Key Laboratory of Molecular Engineering of Polymers, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200433, P.R. China.,Department of Chemistry, Northwestern University, Evanston, Illinois, 60208, United States
| | - Yue-Jian Lin
- State Key Laboratory of Molecular Engineering of Polymers, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200433, P.R. China
| | - Zhen-Hua Li
- State Key Laboratory of Molecular Engineering of Polymers, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200433, P.R. China
| | - J Fraser Stoddart
- Department of Chemistry, Northwestern University, Evanston, Illinois, 60208, United States.,School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia.,Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou, 310021, P.R. China.,ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou, 311215, P.R. China
| | - Guo-Xin Jin
- State Key Laboratory of Molecular Engineering of Polymers, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200433, P.R. China
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15
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Baranov AY, Pritchina EA, Berezin AS, Samsonenko DG, Fedin VP, Belogorlova NA, Gritsan NP, Artem'ev AV. Beyond Classical Coordination Chemistry: The First Case of a Triply Bridging Phosphine Ligand. Angew Chem Int Ed Engl 2021; 60:12577-12584. [PMID: 33749065 DOI: 10.1002/anie.202103037] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Indexed: 02/02/2023]
Abstract
The first example of a triply bridging (μ3 -P) phosphine ligand has been discovered in the crown-shaped [Cu3 (μ2 -Hal)3 L] (Hal=Cl, Br, or I) complexes supported by tris[2-(2-pyridyl)ethyl]phosphine (L). Theoretical analysis completely confirms the observed μ3 -P-bridging pattern, revealing the interaction of the same lone pair of phosphorus with three valence 4s-orbitals of Cu atoms. The presented complexes exhibit outstanding blue phosphorescence (λem =442-465 nm) with the quantum efficiency reaching 100 %. The complex [Cu3 (μ2 -I)3 L] also exhibits remarkable thermo- and mechanochromic luminescence resulting in a sharp change in the emission colour upon external stimuli. These findings essentially contribute to coordination chemistry of the pnictine ligands.
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Affiliation(s)
- Andrey Y Baranov
- Nikolaev Institute of Inorganic Chemistry, SB RAS, 3 Acad. Lavrentiev Ave., 630090, Novosibirsk, Russian Federation
| | - Elena A Pritchina
- Voevodsky Institute of Chemical Kinetics and Combustion, SB RAS, 3 Institutskaya Str., 630090, Novosibirsk, Russian Federation.,Novosibirsk State University, 2, Pirogova Str., Novosibirsk, 630090, Russian Federation
| | - Alexey S Berezin
- Nikolaev Institute of Inorganic Chemistry, SB RAS, 3 Acad. Lavrentiev Ave., 630090, Novosibirsk, Russian Federation
| | - Denis G Samsonenko
- Nikolaev Institute of Inorganic Chemistry, SB RAS, 3 Acad. Lavrentiev Ave., 630090, Novosibirsk, Russian Federation
| | - Vladimir P Fedin
- Nikolaev Institute of Inorganic Chemistry, SB RAS, 3 Acad. Lavrentiev Ave., 630090, Novosibirsk, Russian Federation
| | - Nataliya A Belogorlova
- A. E. Favorsky Irkutsk Institute of Chemistry, SB RAS, 1 Favorsky Str., 664033, Irkutsk, Russian Federation
| | - Nina P Gritsan
- Voevodsky Institute of Chemical Kinetics and Combustion, SB RAS, 3 Institutskaya Str., 630090, Novosibirsk, Russian Federation.,Novosibirsk State University, 2, Pirogova Str., Novosibirsk, 630090, Russian Federation
| | - Alexander V Artem'ev
- Nikolaev Institute of Inorganic Chemistry, SB RAS, 3 Acad. Lavrentiev Ave., 630090, Novosibirsk, Russian Federation
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16
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Abstract
Copper-alumanyl complexes, [LCu-Al(SiNDipp )], where L=carbene=NHCiPr (N,N'-diisopropyl-4,5-dimethyl-2-ylidene) and Me2 CAAC (1-(2,6-diisopropylphenyl)-3,3,5,5-tetramethyl-pyrrolidin-2-ylidene) and featuring unsupported Al-Cu bonds, have been prepared. Divergent reactivity observed with carbodiimides and CO2 implies an ambiphilicity in the Cu-Al interaction that is dependent on the identity of the carbene co-ligand.
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Affiliation(s)
- Han-Ying Liu
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | - Ryan J Schwamm
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | - Michael S Hill
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | - Mary F Mahon
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | | | - Nasir A Rajabi
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
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17
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Petelski AN, Marquez J, Pamies SC, Sosa GL, Peruchena NM. Understanding the Chloride Affinity of Barbiturates for Anion Receptor Design. Chemphyschem 2021; 22:665-674. [PMID: 33538090 DOI: 10.1002/cphc.202100008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 02/02/2021] [Indexed: 11/09/2022]
Abstract
Due to their potential binding sites, barbituric acid (BA) and its derivatives have been used in metal coordination chemistry. Yet their abilities to recognize anions remain unexplored. In this work, we were able to identify four structural features of barbiturates that are responsible for a certain anion affinity. The set of coordination interactions can be finely tuned with covalent decorations at the methylene group. DFT-D computations at the BLYP-D3(BJ)/aug-cc-pVDZ level of theory show that the C-H bond is as effective as the N-H bond to coordinate chloride. An analysis of the electron charge density at the C-H⋅⋅⋅Cl- and N-H⋅⋅⋅Cl- bond critical points elucidates their similarities in covalent character. Our results reveal that the special acidity of the C-H bond shows up when the methylene group moves out of the ring plane and it is mainly governed by the orbital interaction energy. The amide and carboxyl groups are the best choices to coordinate the ion when they act together with the C-H bond. We finally show how can we use this information to rationally improve the recognition capability of a small cage-like complex that is able to coordinate NaCl.
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Affiliation(s)
- Andre Nicolai Petelski
- Departamento de Ingeniería Química, Grupo de Investigación en Química Teórica y Experimental (QUITEX), Universidad Tecnológica Nacional, Facultad Regional Resistencia, French 414, H3500CHJ), Resistencia, Chaco, Argentina.,Instituto de Química Básica y Aplicada del Nordeste Argentino, IQUIBA-NEA, UNNE-CONICET, Avenida Libertad 5460, 3400, Corrientes, Argentina
| | - Josefina Marquez
- Departamento de Ingeniería Química, Grupo de Investigación en Química Teórica y Experimental (QUITEX), Universidad Tecnológica Nacional, Facultad Regional Resistencia, French 414, H3500CHJ), Resistencia, Chaco, Argentina
| | - Silvana Carina Pamies
- Departamento de Ingeniería Química, Grupo de Investigación en Química Teórica y Experimental (QUITEX), Universidad Tecnológica Nacional, Facultad Regional Resistencia, French 414, H3500CHJ), Resistencia, Chaco, Argentina
| | - Gladis Laura Sosa
- Departamento de Ingeniería Química, Grupo de Investigación en Química Teórica y Experimental (QUITEX), Universidad Tecnológica Nacional, Facultad Regional Resistencia, French 414, H3500CHJ), Resistencia, Chaco, Argentina.,Instituto de Química Básica y Aplicada del Nordeste Argentino, IQUIBA-NEA, UNNE-CONICET, Avenida Libertad 5460, 3400, Corrientes, Argentina
| | - Nélida María Peruchena
- Instituto de Química Básica y Aplicada del Nordeste Argentino, IQUIBA-NEA, UNNE-CONICET, Avenida Libertad 5460, 3400, Corrientes, Argentina.,Área de Química Física - Departamento de Química, Laboratorio de Estructura Molecular y Propiedades (LEMyP), Facultad de Ciencias Exactas y Naturales y Agrimensura, Universidad Nacional del Nordeste, Avenida Libertad 5460, 3400, Corrientes, Argentina
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18
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Sharma MK, Rottschäfer D, Neumann B, Stammler HG, Danés S, Andrada DM, van Gastel M, Hinz A, Ghadwal RS. Metalloradical Cations and Dications Based on Divinyldiphosphene and Divinyldiarsene Ligands. Chemistry 2021; 27:5803-5809. [PMID: 33470468 PMCID: PMC8048781 DOI: 10.1002/chem.202100213] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Indexed: 01/09/2023]
Abstract
Metalloradicals are key species in synthesis, catalysis, and bioinorganic chemistry. Herein, two iron radical cation complexes (3‐E)GaCl4 [(3‐E).+ = [{(IPr)C(Ph)E}2Fe(CO)3].+, E = P or As; IPr = C{(NDipp)CH}2, Dipp = 2,6‐iPr2C6H3] are reported as crystalline solids. Treatment of the divinyldipnictenes {(IPr)C(Ph)E}2 (1‐E) with Fe2(CO)9 affords [{(IPr)C(Ph)E}2Fe(CO)3] (2‐E), in which 1‐E binds to the Fe atom in an allylic (η3‐EECvinyl) fashion and functions as a 4e donor ligand. Complexes 2‐E undergo 1e oxidation with GaCl3 to yield (3‐E)GaCl4. Spin density analysis revealed that the unpaired electron in (3‐E).+ is mainly located on the Fe (52–64 %) and vinylic C (30–36 %) atoms. Further 1e oxidation of (3‐E)GaCl4 leads to unprecedented η3‐EECvinyl to η3‐ECvinylCPh coordination shuttling to form the dications (4‐E)(GaCl4)2.
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Affiliation(s)
- Mahendra K Sharma
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Dennis Rottschäfer
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Beate Neumann
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Hans-Georg Stammler
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Sergi Danés
- Allgemeine und Anorganische Chemie, Universität des Saarlandes, Campus C4.1, 66123, Saarbrücken, Germany
| | - Diego M Andrada
- Allgemeine und Anorganische Chemie, Universität des Saarlandes, Campus C4.1, 66123, Saarbrücken, Germany
| | - Maurice van Gastel
- Max-Planck-Institut für Kohlenforschung Molecular Theory and Spectroscopy, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr, 45470, Germany
| | - Alexander Hinz
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, 76131, Karlsruhe, Germany
| | - Rajendra S Ghadwal
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
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19
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Kelemen D, May NV, Andrási M, Gáspár A, Fábián I, Lihi N. High Enzyme Activity of a Binuclear Nickel Complex Formed with the Binding Loops of the NiSOD Enzyme*. Chemistry 2020; 26:16767-16773. [PMID: 32744741 PMCID: PMC7756883 DOI: 10.1002/chem.202002706] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Indexed: 11/08/2022]
Abstract
Detailed equilibrium, spectroscopic and superoxide dismutase (SOD) activity studies are reported on a nickel complex formed with a new metallopeptide bearing two nickel binding loops of NiSOD. The metallopeptide exhibits unique nickel binding ability and the binuclear complex is a major species with 2×(NH2 ,Namide ,S- ,S- ) donor set even in an equimolar solution of the metal ion and the ligand. Nickel(III) species were generated by oxidizing the NiII complexes with KO2 and the coordination modes were identified by EPR spectroscopy. The binuclear complex formed with the binding motifs exhibits superior SOD activity, in this respect it is an excellent model of the native NiSOD enzyme. A detailed kinetic model is postulated that incorporates spontaneous decomposition of the superoxide ion, the dismutation cycle and fast redox degradation of the binuclear complex. The latter process leads to the elimination of the SOD activity. A unique feature of this system is that the NiIII form of the catalyst rapidly accumulates in the dismutation cycle and simultaneously the NiII form becomes a minor species.
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Affiliation(s)
- Dóra Kelemen
- Department of Inorganic and Analytical Chemistry, University of Debrecen, 4032, Debrecen, Hungary
| | - Nóra V May
- Research Centre for Natural Sciences, 1117, Budapest, Hungary
| | - Melinda Andrási
- Department of Inorganic and Analytical Chemistry, University of Debrecen, 4032, Debrecen, Hungary
| | - Attila Gáspár
- Department of Inorganic and Analytical Chemistry, University of Debrecen, 4032, Debrecen, Hungary
| | - István Fábián
- Department of Inorganic and Analytical Chemistry, University of Debrecen, 4032, Debrecen, Hungary.,MTA-DE Redox and Homogeneous Catalytic Reaction Mechanisms, Research Group, University of Debrecen, 4032, Debrecen, Hungary
| | - Norbert Lihi
- Department of Inorganic and Analytical Chemistry, University of Debrecen, 4032, Debrecen, Hungary.,MTA-DE Redox and Homogeneous Catalytic Reaction Mechanisms, Research Group, University of Debrecen, 4032, Debrecen, Hungary
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20
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Suzuki S, Ishida Y, Kameo H, Sakaki S, Kawaguchi H. Counterion Dependence of Dinitrogen Activation and Functionalization by a Diniobium Hydride Anion. Angew Chem Int Ed Engl 2020; 59:13444-13450. [PMID: 32352196 DOI: 10.1002/anie.202006039] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Indexed: 01/10/2023]
Abstract
We report the synthesis of anionic diniobium hydride complexes with a series of alkali metal cations (Li+ , Na+ , and K+ ) and the counterion dependence of their reactivity with N2 . Exposure of these complexes to N2 initially produces the corresponding side-on end-on N2 complexes, the fate of which depends on the nature of countercations. The lithium derivative undergoes stepwise migratory insertion of the hydride ligands onto the aryloxide units, yielding the end-on bridging N2 complex. For the potassium derivative, the N-N bond cleavage takes place along with H2 elimination to form the nitride complex. Treatment of the side-on end-on N2 complex with Me3 SiCl results in silylation of the terminal N atom and subsequent N-N bond cleavage along with H2 elimination, giving the nitride-imide-bridged diniobium complex.
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Affiliation(s)
- Shoi Suzuki
- Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Yutaka Ishida
- Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Hajime Kameo
- Department of Chemistry, Graduate School of Science, Osaka Prefecture University, Gakuen-cho 1-1, Naka-ku, 599-8531, Sakai, Osaka, Japan
| | - Shigeyoshi Sakaki
- Fukui Institute for Fundamental Chemistry, Kyoto University, Takano-nishihiraki-cho 34-4, Sakyo-ku, Kyoto, 606-8103, Japan
| | - Hiroyuki Kawaguchi
- Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
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21
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Woźniczka M, Sutradhar M, Pombeiro AJL, Świątek M, Pająk M, Gądek-Sobczyńska J, Chmiela M, Gonciarz W, Pasternak B, Kufelnicki A. Equilibria in Aqueous Cobalt(II)-Reduced Schiff Base N-(2-hydroxybenzyl)alanine System: Chemical Characterization, Kinetic Analysis, Antimicrobial and Cytotoxic Properties. Molecules 2020; 25:molecules25153462. [PMID: 32751474 PMCID: PMC7436002 DOI: 10.3390/molecules25153462] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 11/16/2022] Open
Abstract
The present study describes the coordination properties of a reduced Schiff base, N-(2-hydroxybenzyl)alanine, towards cobalt(II) using potentiometric as well as spectroscopic (UV-Vis and ESI-MS) methods. The results indicate the formation of six mononuclear complexes showing high stability in aqueous solution. Coordination occurs in the {O−phenolic,N,O−carboxyl} and {N,O−carboxyl} chelation modes, depending on the degree of ligand deprotonation. Examination of the complexation equilibria at pH ca 7, which is important from a biological point of view, allowed to identify two species: [CoL] and [CoL2H]−. The kinetic analysis showed a structural change of those cobalt(II) complexes from octahedral to tetrahedral in accordance with a first-order time relationship. The antimicrobial properties of N-(2-hydroxybenzyl)alanine, cobalt(II) nitrate and of the Co(II) – ligand complexes were determined against Gram-positive bacteria (Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis), Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Helicobacter pylori) and a fungal strain (Candida). The results indicate that the complexes are more active for more strains than the ligand alone. Nevertheless, the complexes induce a higher decrease in the metabolic activity of cells but without damage to nuclei. Tetrahedral structures show stronger anti-cellular toxicity than octahedral complexes, which is most likely due to the higher accessibility of the cobalt(II) center.
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Affiliation(s)
- Magdalena Woźniczka
- Department of Physical and Biocoordination Chemistry, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Lodz, Poland; (M.Ś.); (M.P.); (J.G.-S.); (A.K.)
- Correspondence:
| | - Manas Sutradhar
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal; (M.S.); (A.J.L.P.)
| | - Armando J. L. Pombeiro
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal; (M.S.); (A.J.L.P.)
| | - Mirosława Świątek
- Department of Physical and Biocoordination Chemistry, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Lodz, Poland; (M.Ś.); (M.P.); (J.G.-S.); (A.K.)
| | - Marek Pająk
- Department of Physical and Biocoordination Chemistry, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Lodz, Poland; (M.Ś.); (M.P.); (J.G.-S.); (A.K.)
| | - Joanna Gądek-Sobczyńska
- Department of Physical and Biocoordination Chemistry, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Lodz, Poland; (M.Ś.); (M.P.); (J.G.-S.); (A.K.)
| | - Magdalena Chmiela
- Department of Immunology and Infectious Biology, Institute of Microbiology, Biotechnology and Immunology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland; (M.C.); (W.G.)
| | - Weronika Gonciarz
- Department of Immunology and Infectious Biology, Institute of Microbiology, Biotechnology and Immunology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland; (M.C.); (W.G.)
| | - Beata Pasternak
- Department of Organic Chemistry, Faculty of Chemistry, University of Lodz, Tamka 12, 91-403 Lodz, Poland;
| | - Aleksander Kufelnicki
- Department of Physical and Biocoordination Chemistry, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Lodz, Poland; (M.Ś.); (M.P.); (J.G.-S.); (A.K.)
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22
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Yi D, Lu F, Zhang F, Liu S, Zhou B, Gao D, Wang X, Yao J. Regulating Charge Transfer of Lattice Oxygen in Single-Atom-Doped Titania for Hydrogen Evolution. Angew Chem Int Ed Engl 2020; 59:15855-15859. [PMID: 32293087 DOI: 10.1002/anie.202004510] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Indexed: 11/08/2022]
Abstract
Single-atom catalysts have attracted much attention. Reported herein is that regulating charge transfer of lattice oxygen atoms in serial single-atom-doped titania enables tunable hydrogen evolution reaction (HER) activity. First-principles calculations disclose that the activity of lattice oxygen for the HER can be regularly promoted by substituting its nearest metal atom, and doping-induced charge transfer plays an essential role. Besides, the realm of the charge transfer of the active site can be enlarged to the second nearest atom by creating oxygen vacancies, resulting in further optimization for the HER. Various single-atom-doped titania nanosheets were fabricated to validate the proposed model. Taking advantage of the localized charge transfer to the lattice atom is demonstrated to be feasible for realizing precise regulation of the electronic structures and thus catalytic activity of the nanosheets.
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Affiliation(s)
- Ding Yi
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,Department of Physics, School of Science, Beijing Jiaotong University, Beijing, 100044, China
| | - Fei Lu
- Department of Physics, School of Science, Beijing Jiaotong University, Beijing, 100044, China
| | - Fengchu Zhang
- Department of Physics, School of Science, Beijing Jiaotong University, Beijing, 100044, China
| | - Shoujie Liu
- Chemistry and Chemical Engineering Guangdong Laboratory, Shantou, 515031, China
| | - Bo Zhou
- Chemistry and Chemical Engineering Guangdong Laboratory, Shantou, 515031, China
| | - Denglei Gao
- Department of Physics, School of Science, Beijing Jiaotong University, Beijing, 100044, China
| | - Xi Wang
- Department of Physics, School of Science, Beijing Jiaotong University, Beijing, 100044, China
| | - Jiannian Yao
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,Chemistry and Chemical Engineering Guangdong Laboratory, Shantou, 515031, China
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23
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Katoh K, Yasuda N, Damjanović M, Wernsdorfer W, Breedlove BK, Yamashita M. Manipulation of the Coordination Geometry along the C 4 Rotation Axis in a Dinuclear Tb 3+ Triple-Decker Complex via a Supramolecular Approach. Chemistry 2020; 26:4805-4815. [PMID: 31984579 DOI: 10.1002/chem.201905400] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 01/21/2020] [Indexed: 01/02/2023]
Abstract
A supramolecular complex (1⋅C60 ) was prepared by assembling (C60-Ih)[5,6]fullerene (C60 ) with the dinuclear Tb3+ triple-decker complex [(TPP)Tb(Pc)Tb(TPP)] (1: Tb3+ =trivalent terbium ion, Pc2- =phthalocyaninato, TPP2- =tetraphenylporphyrinato) with quasi-D4h symmetry to investigate the relationship between the coordination symmetry and single-molecule magnet (SMM) properties. Tb3+ -Pc triple-decker complexes (Tb2 Pc3 ) have an important advantage over Tb3+ -Pc double-decker complexes (TbPc2 ) since the magnetic relaxation processes correspond to the Zeeman splitting when there are two 4f spin systems. The two Tb3+ sites of 1 are equivalent, and the twist angle (φ) was determined to be 3.62°. On the other hand, the two Tb3+ sites of 1⋅C60 are not equivalent. The φ values for sites Tb1 and Tb2 were determined to be 3.67° and 33.8°, respectively, due to a change in the coordination symmetry of 1 upon association with C60 . At 1.8 K, 1 and 1⋅C60 undergo different magnetic relaxations, and the changes in the ground state affect the spin dynamics. Although 1 and 1⋅C60 relax via QTM in a zero applied magnetic field (H), H dependencies of the magnetic relaxation times (τ) for H>1500 Oe are similar. On the other hand, for H<1500 Oe, the τ values have different behaviors since the off-diagonal terms ( B k q ; q ≠ 0 ) affect the magnetic relaxation mechanism. From temperature (T) and H dependences of τ, spin-phonon interactions along with direct and Raman mechanisms explain the spin dynamics. We believe that a supramolecular method can be used to control the magnetic anisotropy along the C4 rotation axis and the spin dynamic properties in dinuclear Ln3+ -Pc multiple-decker complexes.
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Affiliation(s)
- Keiichi Katoh
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi, 980-8578, Japan
| | - Nobuhiro Yasuda
- Diffraction and Scattering Division, Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan
| | - Marko Damjanović
- Institute of Nanotechnology, KIT, 76344, Eggenstein-Leopoldshafen, Germany
| | - Wolfgang Wernsdorfer
- Institute of Nanotechnology, KIT, 76344, Eggenstein-Leopoldshafen, Germany.,Physikalisches Institut, KIT, Wolfgang-Gaede-Str. 1, 76131, Karlsruhe, Germany.,Institut Néel, CNRS, 38042, Grenoble, France
| | - Brian K Breedlove
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi, 980-8578, Japan
| | - Masahiro Yamashita
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi, 980-8578, Japan.,WPI Research Center, Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.,School of Materials Science and Engineering, Nankai University, Tianjin, 300350, P. R. China
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24
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Park H, Lee D. Ligand Taxonomy for Bioinorganic Modeling of Dioxygen-Activating Non-Heme Iron Enzymes. Chemistry 2020; 26:5916-5926. [PMID: 31909506 DOI: 10.1002/chem.201904975] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 01/04/2020] [Indexed: 12/15/2022]
Abstract
Novel functions emerge from novel structures. To develop efficient catalytic systems for challenging chemical transformations, chemists often seek inspirations from enzymatic catalysis. A large number of iron complexes supported by nitrogen-rich multidentate ligands have thus been developed to mimic oxo-transfer reactivity of dioxygen-activating metalloenzymes. Such efforts have significantly advanced our understanding of the reaction mechanisms by trapping key intermediates and elucidating their geometric and electronic properties. Critical to the success of this biomimetic approach is the design and synthesis of elaborate ligand systems to balance the thermodynamic stability, structural adaptability, and chemical reactivity. In this Concept article, representative design strategies for biomimetic atom-transfer chemistry are discussed from the perspectives of "ligand builders". Emphasis is placed on how the primary coordination sphere is constructed, and how it can be elaborated further by rational design for desired functions.
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Affiliation(s)
- Hyunchang Park
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea
| | - Dongwhan Lee
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea
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25
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Balogh RK, Gyurcsik B, Hunyadi‐Gulyás É, Schell J, Thulstrup PW, Hemmingsen L, Jancsó A. C-terminal Cysteines of CueR Act as Auxiliary Metal Site Ligands upon Hg II Binding-A Mechanism To Prevent Transcriptional Activation by Divalent Metal Ions? Chemistry 2019; 25:15030-15035. [PMID: 31365771 PMCID: PMC6899792 DOI: 10.1002/chem.201902940] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Indexed: 01/20/2023]
Abstract
Intracellular CuI is controlled by the transcriptional regulator CueR, which effectively discriminates between monovalent and divalent metal ions. It is intriguing that HgII does not activate transcription, as bis-thiolate metal sites exhibit high affinity for HgII . Here the binding of HgII to CueR and a truncated variant, ΔC7-CueR, without the last 7 amino acids at the C-terminus including a conserved CCHH motif is explored. ESI-MS demonstrates that up to two HgII bind to CueR, while ΔC7-CueR accommodates only one HgII . 199m Hg PAC and UV absorption spectroscopy indicate HgS2 structure at both the functional and the CCHH metal site. However, at sub-equimolar concentrations of HgII at pH 8.0, the metal binding site displays an equilibrium between HgS2 and HgS3 , involving cysteines from both sites. We hypothesize that the C-terminal CCHH motif provides auxiliary ligands that coordinate to HgII and thereby prevents activation of transcription.
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Affiliation(s)
- Ria K. Balogh
- Department of Inorganic and Analytical ChemistryUniversity of SzegedDóm tér 76720SzegedHungary
| | - Béla Gyurcsik
- Department of Inorganic and Analytical ChemistryUniversity of SzegedDóm tér 76720SzegedHungary
| | - Éva Hunyadi‐Gulyás
- Laboratory of Proteomics ResearchInstitute of Biochemistry, Biological Research Centre of the Hungarian Academy of SciencesTemesvári krt. 626726SzegedHungary
| | - Juliana Schell
- Institute for Materials Science and Center for Nanointegration Duisburg-Essen (CENIDE)University of Duisburg-Essen, 45141 Essen (Germany), European Organization for Nuclear Research (CERN)1211GenevaSwitzerland
| | - Peter W. Thulstrup
- Department of ChemistryUniversity of CopenhagenUniversitetsparken 52100CopenhagenDenmark
| | - Lars Hemmingsen
- Department of ChemistryUniversity of CopenhagenUniversitetsparken 52100CopenhagenDenmark
| | - Attila Jancsó
- Department of Inorganic and Analytical ChemistryUniversity of SzegedDóm tér 76720SzegedHungary
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26
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Carmona M, Ferrer J, Rodríguez R, Passarelli V, Lahoz FJ, García-Orduña P, Cañadillas-Delgado L, Carmona D. Reversible Activation of Water by an Air- and Moisture-Stable Frustrated Rhodium Nitrogen Lewis Pair. Chemistry 2019; 25:13665-13670. [PMID: 31353749 DOI: 10.1002/chem.201902452] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/12/2019] [Indexed: 12/15/2022]
Abstract
[Cp*Rh(κ3 N,N',P-L)][SbF6 ] (Cp*=C5 Me5 ), bearing a guanidine-derived phosphano ligand L, behaves as a "dormant" frustrated Lewis pair and activates H2 and H2 O in a reversible manner. When D2 O is employed, a facile H/D exchange at the Cp* ring takes place through sequential C(sp3 )-H bond activation.
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Affiliation(s)
- María Carmona
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Joaquina Ferrer
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Ricardo Rodríguez
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Vincenzo Passarelli
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain.,Centro Universitario de la Defensa, Ctra. Huesca s/n, 50090, Zaragoza, Spain
| | - Fernando J Lahoz
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Pilar García-Orduña
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Laura Cañadillas-Delgado
- Centro Universitario de la Defensa, Ctra. Huesca s/n, 50090, Zaragoza, Spain.,Institut Laue-Langevin, 71 Avenue des Martyrs, Grenoble, 38042, France
| | - Daniel Carmona
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
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27
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Li J, Xia W, Wang T, Zheng L, Lai Y, Pan J, Jiang C, Song L, Wang M, Zhang H, Chen N, Chen G, He J. A Facile Route for Constructing Effective Cu-N x Active Sites for Oxygen Reduction Reaction. Chemistry 2019; 26:4070-4079. [PMID: 31633249 DOI: 10.1002/chem.201903822] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 10/09/2019] [Indexed: 11/10/2022]
Abstract
The coordination number between copper and nitrogen in copper/nitrogen-based electrocatalysts is important for boosting the oxygen reduction reaction (ORR). However, it is difficult to control unsaturated copper/nitrogen constructions as well as to compare their ORR performances in similar carbon matrices in a simple yet efficient manner. In this study, we have easily attained two types of Cu+ -N2 and Cu2+ -N4 constructions simply by etching pyrolyzed Cu-doped zeolitic imidazolate framework nanoleaves (Cu-ZIF-L) with sulfuric acid or nitric acid, respectively. X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectra were recorded to further confirm the different copper/nitrogen constructions after the different acid treatments. Electrochemical studies have demonstrated that Cu+ -N2 sites are more active in boosting the ORR performance than Cu2+ -N4 sites. Furthermore, Cu-N/C-H2 SO4 , used as an air cathode in a zinc-air battery, exhibited excellent performance and stability.
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Affiliation(s)
- Jingjing Li
- College of Materials Science and Technology, Jiangsu Key Laboratory of, Electrochemical Energy Storage Technologies, Nanjing University of, Aeronautics and Astronautics, 210016, Nanjing, P. R. China
| | - Wei Xia
- College of Materials Science and Technology, Jiangsu Key Laboratory of, Electrochemical Energy Storage Technologies, Nanjing University of, Aeronautics and Astronautics, 210016, Nanjing, P. R. China
| | - Tao Wang
- College of Materials Science and Technology, Jiangsu Key Laboratory of, Electrochemical Energy Storage Technologies, Nanjing University of, Aeronautics and Astronautics, 210016, Nanjing, P. R. China
| | - Lirong Zheng
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Yue Lai
- College of Materials Science and Technology, Jiangsu Key Laboratory of, Electrochemical Energy Storage Technologies, Nanjing University of, Aeronautics and Astronautics, 210016, Nanjing, P. R. China
| | - Junjie Pan
- College of Materials Science and Technology, Jiangsu Key Laboratory of, Electrochemical Energy Storage Technologies, Nanjing University of, Aeronautics and Astronautics, 210016, Nanjing, P. R. China
| | - Cheng Jiang
- College of Materials Science and Technology, Jiangsu Key Laboratory of, Electrochemical Energy Storage Technologies, Nanjing University of, Aeronautics and Astronautics, 210016, Nanjing, P. R. China
| | - Li Song
- College of Materials Science and Technology, Jiangsu Key Laboratory of, Electrochemical Energy Storage Technologies, Nanjing University of, Aeronautics and Astronautics, 210016, Nanjing, P. R. China
| | - Mengyu Wang
- College of Materials Science and Technology, Jiangsu Key Laboratory of, Electrochemical Energy Storage Technologies, Nanjing University of, Aeronautics and Astronautics, 210016, Nanjing, P. R. China
| | - Huting Zhang
- College of Materials Science and Technology, Jiangsu Key Laboratory of, Electrochemical Energy Storage Technologies, Nanjing University of, Aeronautics and Astronautics, 210016, Nanjing, P. R. China
| | - Na Chen
- College of Materials Science and Technology, Jiangsu Key Laboratory of, Electrochemical Energy Storage Technologies, Nanjing University of, Aeronautics and Astronautics, 210016, Nanjing, P. R. China
| | - Guang Chen
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, P. R. China.,University of the Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Jianping He
- College of Materials Science and Technology, Jiangsu Key Laboratory of, Electrochemical Energy Storage Technologies, Nanjing University of, Aeronautics and Astronautics, 210016, Nanjing, P. R. China
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28
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Cleveland GT, Radosevich AT. A Nontrigonal Tricoordinate Phosphorus Ligand Exhibiting Reversible "Nonspectator" L/X-Switching. Angew Chem Int Ed Engl 2019; 58:15005-15009. [PMID: 31469492 DOI: 10.1002/anie.201909686] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Indexed: 11/11/2022]
Abstract
We report here a "nonspectator" behavior for an unsupported L-function σ3 -P ligand (i.e. P{N[o-NMe-C6 H4 ]2 }, 1a) in complex with the cyclopentadienyliron dicarbonyl cation (Fp+ ). Treatment of 1a⋅Fp+ with [(Me2 N)3 S][Me3 SiF2 ] results in fluoride addition to the P-center, giving the isolable crystalline fluorometallophosphorane 1aF ⋅Fp that allows a crystallographic assessment of the variance in the Fe-P bond as a function of P-coordination number. The nonspectator reactivity of 1a⋅Fp+ is rationalized on the basis of electronic structure arguments and by comparison to trigonal analogue (Me2 N)3 P⋅Fp+ (i.e. 1b⋅Fp+ ), which is inert to fluoride addition. These observations establish a nonspectator L/X-switching in (σ3 -P)-M complexes by reversible access to higher-coordinate phosphorus ligand fragments.
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Affiliation(s)
- Gregory T Cleveland
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Alexander T Radosevich
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
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29
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Wilden A, Kowalski PM, Klaß L, Kraus B, Kreft F, Modolo G, Li Y, Rothe J, Dardenne K, Geist A, Leoncini A, Huskens J, Verboom W. Unprecedented Inversion of Selectivity and Extraordinary Difference in the Complexation of Trivalent f Elements by Diastereomers of a Methylated Diglycolamide. Chemistry 2019; 25:5507-5513. [PMID: 30720905 DOI: 10.1002/chem.201806161] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 02/05/2019] [Indexed: 11/10/2022]
Abstract
When considering f elements, solvent extraction is primarily used for the removal of lanthanides from ore and their recycling, as well as for the separation of actinides from used nuclear fuel. Understanding the complexation mechanism of metal ions with organic extractants, particularly the influence of their molecular structure on complex formation is of fundamental importance. Herein, we report an extraordinary (up to two orders of magnitude) change in the extraction efficiency of f elements with two diastereomers of dimethyl tetraoctyl diglycolamide (Me2 -TODGA), which only differ in the orientation of a single methyl group. Solvent extraction techniques, extended X-ray absorption fine structure (EXAFS) measurements, and density functional theory (DFT) based ab initio calculations were used to understand their complex structures and to explain their complexation mechanism. We show that the huge differences observed in extraction selectivity results from a small change in the complexation of nitrate counter-ions caused by the different orientation of one methyl group in the backbone of the extractant. The obtained results give a significant new insight into metal-ligand complexation mechanisms, which will promote the development of more efficient separation techniques.
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Affiliation(s)
- Andreas Wilden
- Institut für Energie- und Klimaforschung-Nukleare Entsorgung, und Reaktorsicherheit- (IEK-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Strasse 1, 52428, Jülich, Germany.,JARA High-Performance Computing, Schinkelstrasse 2, 52062, Aachen, Germany
| | - Piotr M Kowalski
- Institut für Energie- und Klimaforschung-Nukleare Entsorgung, und Reaktorsicherheit- (IEK-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Strasse 1, 52428, Jülich, Germany.,JARA High-Performance Computing, Schinkelstrasse 2, 52062, Aachen, Germany
| | - Larissa Klaß
- Institut für Energie- und Klimaforschung-Nukleare Entsorgung, und Reaktorsicherheit- (IEK-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Strasse 1, 52428, Jülich, Germany.,JARA High-Performance Computing, Schinkelstrasse 2, 52062, Aachen, Germany
| | - Benjamin Kraus
- Institut für Energie- und Klimaforschung-Nukleare Entsorgung, und Reaktorsicherheit- (IEK-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Strasse 1, 52428, Jülich, Germany.,JARA High-Performance Computing, Schinkelstrasse 2, 52062, Aachen, Germany
| | - Fabian Kreft
- Institut für Energie- und Klimaforschung-Nukleare Entsorgung, und Reaktorsicherheit- (IEK-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Strasse 1, 52428, Jülich, Germany.,JARA High-Performance Computing, Schinkelstrasse 2, 52062, Aachen, Germany
| | - Giuseppe Modolo
- Institut für Energie- und Klimaforschung-Nukleare Entsorgung, und Reaktorsicherheit- (IEK-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Strasse 1, 52428, Jülich, Germany.,JARA High-Performance Computing, Schinkelstrasse 2, 52062, Aachen, Germany
| | - Yan Li
- Institut für Energie- und Klimaforschung-Nukleare Entsorgung, und Reaktorsicherheit- (IEK-6), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Strasse 1, 52428, Jülich, Germany.,JARA High-Performance Computing, Schinkelstrasse 2, 52062, Aachen, Germany
| | - Jörg Rothe
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), 76021, Karlsruhe, Germany
| | - Kathy Dardenne
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), 76021, Karlsruhe, Germany
| | - Andreas Geist
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), 76021, Karlsruhe, Germany
| | - Andrea Leoncini
- Laboratory of Molecular Nanofabrication, Mesa+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500, AE, Enschede, The Netherlands
| | - Jurriaan Huskens
- Laboratory of Molecular Nanofabrication, Mesa+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500, AE, Enschede, The Netherlands
| | - Willem Verboom
- Laboratory of Molecular Nanofabrication, Mesa+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500, AE, Enschede, The Netherlands
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30
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Devillard M, Ehlers A, Siegler MA, van der Vlugt JI. Selective Carbanion-Pyridine Coordination of a Reactive P,N Ligand to Rh I. Chemistry 2019; 25:3875-3883. [PMID: 30600857 PMCID: PMC6519283 DOI: 10.1002/chem.201805504] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 12/12/2018] [Indexed: 01/12/2023]
Abstract
Ligands with reactive carbon sites in the periphery of a metal center have emerged as a powerful approach for metal-ligand bond activation. These reactive carbon sites are commonly generated by deprotonation strategies. Carbon-silicon bond cleavage is a potential alternative to access such constructs. Herein, the monodesilylation of bis-silyl-substituted P,N scaffold PNSi2 in the coordination sphere of [RhI (Cl)(CO)(PNSi2 )] (1) with sodium azide is disclosed. This affords a unique dinucleating anionic κ2 -C,N-κ1 -P ligand with a carbanionic methine carbon atom directly bound to rhodium as part of a four-membered Rh-N-C-C rhodacycle. This dimer undergoes meta-pyridine C-H activation facilitated by weak bases, which leads to a desymmetrization of the system and provides a σ,π-bridging 3-pyridyl fragment bound to RhI . The facile Si-C cleavage strategy may pave the way to studying the reactivity and functionalization of a variety of κ2 -C,N-coordinated pyridine scaffolds for selective transformations.
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Affiliation(s)
- Marc Devillard
- van ‘t Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XHAmsterdamThe Netherlands
| | - Andreas Ehlers
- van ‘t Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XHAmsterdamThe Netherlands
- Department of ChemistryUniversity of Johannesburg, P.O. Box 254Auckland ParkJohannesburgSouth Africa
| | - Maxime A. Siegler
- Department of ChemistryJohns Hopkins University3400 N Charles StreetBaltimoreMD21218USA
| | - Jarl Ivar van der Vlugt
- van ‘t Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XHAmsterdamThe Netherlands
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31
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Heathman CR, Grimes TS, Jansone-Popova S, Roy S, Bryantsev VS, Zalupski PR. Influence of a Pre-organized N-Donor Group on the Coordination of Trivalent Actinides and Lanthanides by an Aminopolycarboxylate Complexant. Chemistry 2019; 25:2545-2555. [PMID: 30444030 DOI: 10.1002/chem.201804723] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 11/14/2018] [Indexed: 01/17/2023]
Abstract
The thermodynamic influence of a pre-organized N-donor group on the coordination of trivalent actinides and lanthanides by an aqueous aminopolycarboxylate complexant has been investigated. The synthesized reagent, N-2-methylpicolinate-ethylenediamine-N,N',N'-triacetic acid (EDTA-Mpic), resembles ethylenediamine-N,N,N',N'-tetraacetic acid (EDTA) with a single acetate pendant arm replaced by a 6-carboxypyridin-2-ylmethyl group. The rigid N-donor picolinate functionality has a profound impact on ligand protonation and trivalent f element complexation equilibria, as demonstrated by potentiometric, spectroscopic, and liquid/liquid metal-partitioning studies as well as by molecular dynamics calculations. Relative to diethylenetriamine-N,N,N',N'',N''-pentaacetic acid (DTPA), the ability to preferentially bind trivalent actinides over trivalent lanthanides was moderately lowered due to the presence of the N-(6-carboxypyridin-2-ylmethyl) substituent. The structural modification substantially amplifies the total ligand acidity of EDTA-Mpic. As a result the complexant sustains the metal complexation and efficient An3+ /Ln3+ differentiation in aqueous mixtures of unprecedented acidity for this class of reagents.
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Affiliation(s)
- Colt R Heathman
- Aqueous Separations and Radiochemistry, Idaho National Laboratory, Idaho Falls, ID, 83415, USA
| | - Travis S Grimes
- Aqueous Separations and Radiochemistry, Idaho National Laboratory, Idaho Falls, ID, 83415, USA
| | - Santa Jansone-Popova
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Santanu Roy
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | | | - Peter R Zalupski
- Aqueous Separations and Radiochemistry, Idaho National Laboratory, Idaho Falls, ID, 83415, USA
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32
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Abstract
Boron and aluminum are lighter Group 13 elements, found in daily life commodities, and considered environmentally benign. Nevertheless, they markedly differ in their elemental properties (e.g., metal character, atomic radius). The use of Lewis acidic complexes of boron and aluminum for methods of bond activation and catalysis (e.g., hydrogenation of unsaturated substrates, polymerization of olefins and epoxides) is quickly expanding. The introduction of cationic charge may boost the metalloid-centered Lewis acidity and allow for its fine-tuning particularly with regard to preference for "hard" or "soft" Lewis bases (i.e., substrates). Especially the isolation of low-coordinate cations (number of ligand atoms smaller than four) demands elaborate techniques of thermodynamic and kinetic stabilization (i.e., electronic saturation and steric shielding) by a ligand system. Furthermore, the properties of the solvent and the counteranion must be considered with care. Here, selected examples of boron and aluminum cations are described.
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Affiliation(s)
- Daniel Franz
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstr. 4, 85748, Garching bei München, Germany
| | - Shigeyoshi Inoue
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstr. 4, 85748, Garching bei München, Germany
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33
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Klein J, Beerhues J, Schweinfurth D, van der Meer M, Gazvoda M, Lahiri GK, Košmrlj J, Sarkar B. Versatile Coordination of Azocarboxamides: Redox-Triggered Change of the Chelating Binding Pocket in Ruthenium Complexes. Chemistry 2018; 24:18020-18031. [PMID: 30136748 DOI: 10.1002/chem.201803606] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 08/22/2018] [Indexed: 11/09/2022]
Abstract
Azocarboxamides occupy a special place among azo ligands owing to their versatility for metal coordination. Herein ruthenium complexes with two different azocarboxamide ligands that differ in the presence (or not) of a coordinating pyridyl heterocycle are presented. By making full use of the O,N(amide), N(azo), and N(pyridyl) coordinating sites, the first diruthenium complex that is bridged by an azo ligand containing two different binding pockets was obtained. Moreover, it was conclusively proven that, in the mononuclear complexes, oxidation at the ruthenium center leads to a complete change of coordination at the chelating binding pocket. The complexes were characterized by NMR spectroscopy, mass spectrometry, and single-crystal X-ray diffraction. Additionally, the mechanism of the aforementioned redox-triggered change in the chelating binding pocket and the electronic structures of all the complexes were investigated by a combination of electrochemistry, UV/Vis/NIR/EPR spectroelectrochemistry, and DFT calculations. This is first instance in which a redox-driven change in the complete chelating binding pocket has been observed in a ruthenium complex as well as with azo-based ligands. These results thus show the potential of these versatile azocarboxamide ligands to act as redox-driven switches with possible relevance to electrocatalysis.
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Affiliation(s)
- Johannes Klein
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstrasse 34-36, 14195, Berlin, Germany
| | - Julia Beerhues
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstrasse 34-36, 14195, Berlin, Germany
| | - David Schweinfurth
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstrasse 34-36, 14195, Berlin, Germany
| | - Margarethe van der Meer
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstrasse 34-36, 14195, Berlin, Germany
| | - Martin Gazvoda
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1000, Ljubljana, Slovenia
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Janez Košmrlj
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1000, Ljubljana, Slovenia
| | - Biprajit Sarkar
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstrasse 34-36, 14195, Berlin, Germany
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34
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Taguchi HO, Tanigawa I, Takeuchi K, Ozawa F. On the Geometrical Stability of Square-Planar Platinum(0) Complexes That Bear a PNP-Pincer-Type Phosphaalkene Ligand (Eind 2 -BPEP). Chemistry 2018; 24:17055-17061. [PMID: 30350899 DOI: 10.1002/chem.201803097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/05/2018] [Indexed: 11/12/2022]
Abstract
The four-coordinate Pt0 complex [Pt(PPh3 )(Eind2 -BPEP)] (Eind=1,1,3,3,5,5,7,7-octaethyl-1,2,3,5,6,7-hexahydro-s-indacen-4-yl; BPEP=2,6-bis(1-phenyl-2-phosphaethenyl)pyridine), which bears a PNP-pincer-type phosphaalkene ligand (Eind2 -BPEP; PNP=N,N-bis(diphenylphosphine)-2,6-diaminopyridine), were found to adopt a square-planar configuration around the Pt center (τ4 =0.11). This coordination geometry is very uncommon for formal d10 complexes. In this study, a series of ligands with different electronic properties (i.e., DMAP, 2,6-lutidine, PMe3 , tBuNC, and CO) were introduced in place of PPh3 , and their effects on the coordination geometry were examined. X-ray diffraction analysis revealed that all complexes adopted a square-planar configuration (τ4 =0.20-0.27). In contrast, DFT calculations indicated that the geometrical stability towards distortion around Pt varied with the ligand. The complexes with pyridine-based ligands had rigid planar structures, whereas those with π-accepting ligands, such as CO, were relatively flexible towards distortion. The electronic effects of the ligands were reflected in the spectroscopic properties of the complexes, which showed a large color change in the near-infrared region.
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Affiliation(s)
- Hiro-Omi Taguchi
- International Research Center for Elements Science (IRCELS), Institute for Chemical Research & IRCCS, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Ippei Tanigawa
- International Research Center for Elements Science (IRCELS), Institute for Chemical Research & IRCCS, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Katsuhiko Takeuchi
- International Research Center for Elements Science (IRCELS), Institute for Chemical Research & IRCCS, Kyoto University, Uji, Kyoto 611-0011, Japan.,Present Address: Interdisciplinary Research Center for Catalytic Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, 305-8565, Japan
| | - Fumiyuki Ozawa
- International Research Center for Elements Science (IRCELS), Institute for Chemical Research & IRCCS, Kyoto University, Uji, Kyoto 611-0011, Japan
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35
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Abstract
We present here the synthesis of chiral BINOL-derived (BINOL=1,1'-bi-2-naphthol) bisamine and bispyridine-aldehyde building blocks that can be used for the self-assembly of novel chiral FeII 2 L3 cages when mixed with an iron(II) precursor. The properties of a series of chiral cages were studied by NMR and circular dichroism (CD) spectroscopy, cold-spray ionization MS, and molecular modeling. Upon formation of the M2 L3 cages, the iron corners can adopt various isomeric forms: mer, fac-Δ, or fac-Λ. We found that the coordination geometry around the metal centers in R-Cages 1 and 2 were influenced by the chiral BINOL backbone only to a limited extent, as a mixture of cages was formed with fac and mer configurations at the iron corners. However, single cage species (fac-RR-Cage and fac-RS-Cage) that are enantiopure and highly symmetric were obtained by generating these chiral M2 L3 cages by using the bispyridine-aldehyde building blocks in combination with chiral amine moieties to form pyridylimine ligands for coordination to iron. Next to consistent NMR spectra, the CD spectra confirm the configurations fac-(Λ,Λ) and fac-(Δ,Δ) corresponding to RR- and RS-Cage, respectively.
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Affiliation(s)
- Bin Sun
- Homogeneous, Bioinspired and Supramolecular Catalysis, van 't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098XHAmsterdamThe Netherlands
| | - Sandra S. Nurttila
- Homogeneous, Bioinspired and Supramolecular Catalysis, van 't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098XHAmsterdamThe Netherlands
| | - Joost N. H. Reek
- Homogeneous, Bioinspired and Supramolecular Catalysis, van 't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098XHAmsterdamThe Netherlands
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36
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Stuhl C, Maichle-Mössmer C, Anwander R. Magnesium Stung by Nonclassical Scorpionate Ligands: Synthesis and Cone-Angle Calculations. Chemistry 2018; 24:14254-14268. [PMID: 29993157 DOI: 10.1002/chem.201803067] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 07/11/2018] [Indexed: 12/24/2022]
Abstract
A series of tris(pyrazolyl)alkane (RCTp) scorpionate ligands of the type RCTp3-R' (R=Me, nBu, SiMe3 ; R'=H, Me, Ph, iPr, tBu) were synthesized and their ability to coordinate methylmagnesium moieties was examined. The reaction of Mg(AlMe4 )2 with neutral proligands HCTp3-Ph or Me3 SiCTp3-Me , containing a non-innocent backbone methine moiety, led to deprotonation/rearrangement and SiMe3 /AlMe3 exchange to afford [(Me3 AlCTp3-Ph )2 Mg] and [(Me3 AlCTp3-Me )Mg(AlMe4 )], respectively, with monoanionic tripodal ligands. Treatment of sterically less demanding RCTp3-R' with Mg(AlMe4 )2 produced isostructural dicationic "metal-in-a-box" complexes of the type [(RCTp3-R' )2 Mg][AlMe4 ]2 (R=Me, nBu; R'=H, Me). Utilization of the superbulky ligands MeCTp3-Ph and MeCTp3-tBu gave monocationic complexes [(MeCTp3-Ph )MgMe][AlMe4 ] and [(MeCTp3-tBu )MgMe][Al2 Me7 ] as separated ion pairs. The reaction of Mg(AlMe4 )2 with nBuCTp3-Ph led to the formation of the dimagnesium complex [{(nBuCTp3-Ph )Mg(AlMe4 )}2 (μ-CH3 )], which features a bridging methyl moiety and terminal η1 -coordinated tetramethylaluminato ligands. Isopropyl-substituted ligand MeCTp3-iPr emerged from further fine-tuning of the steric and electronic parameters and, upon reaction with Mg(AlMe4 )2 , gave (MeCTp3-iPr )Mg(AlMe4 )2 ; this represents the first example of a magnesium bis(alkyl) complex with an intact RCTp3-R' ligand. The exact ligand cone angles Θ° of all magnesium complexes were determined according to the mathematical analysis developed by Allen et al. [J. Comput. Chem. 2013, 34, 1189-1197].
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Affiliation(s)
- Christoph Stuhl
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Cäcilia Maichle-Mössmer
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Reiner Anwander
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
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37
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Klein JEMN, Havenith RWA, Knizia G. The Pentagonal-Pyramidal Hexamethylbenzene Dication: Many Shades of Coordination Chemistry at Carbon. Chemistry 2018; 24:12340-12345. [PMID: 29341342 PMCID: PMC6120489 DOI: 10.1002/chem.201705812] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Indexed: 12/15/2022]
Abstract
A recent report on the crystal structure of the pentagonal-pyramidal hexamethylbenzene dication C6 (CH3 )62+ by Malischewski and Seppelt [Angew. Chem. Int. Ed. 2017, 56, 368] confirmed the structural proposal made in the first report of this compound in 1973 by Hogeveen and Kwant [Tetrahedron Lett. 1973, 14, 1665]. The widespread attention that this compound quickly gained led us to reinvestigate its electronic structure. On the basis of intrinsic bond orbital analysis, effective oxidation state analysis, ring current analysis, and comparison with well-established coordination complexes, it is demonstrated that the central carbon atom behaves like a transition metal. The central (apical) carbon atom, although best described as a highly Lewis-acidic carbon atom coordinated with an anionic cyclopentadienyl ligand, is also capable of acting as an electron-pair donor to a formal CH3+ group. The different roles of coordination chemistry are discussed.
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Affiliation(s)
- Johannes E. M. N. Klein
- Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of Science and EngineeringUniversity of GroningenNijenborgh 49747AG GroningenThe Netherlands
| | - Remco W. A. Havenith
- Zernike Institute for Advanced Materials and Stratingh Institute for ChemistryUniversity of GroningenNijenborgh 49747AG GroningenThe Netherlands
- Ghent Quantum Chemistry Group, Department of Inorganic and Physical ChemistryGhent UniversityKrijgslaan 281 (S3)9000GentBelgium
| | - Gerald Knizia
- Department of ChemistryPennsylvania State University401A Chemistry Bldg; University ParkPA16802USA
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38
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Wang SY, Huang JY, Liang YP, He YJ, Chen YS, Zhan YY, Hiraoka S, Liu YH, Peng SM, Chan YT. Multicomponent Self-Assembly of Metallo-Supramolecular Macrocycles and Cages through Dynamic Heteroleptic Terpyridine Complexation. Chemistry 2018; 24:9274-9284. [PMID: 29714039 DOI: 10.1002/chem.201801753] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 04/28/2018] [Indexed: 12/31/2022]
Abstract
Spontaneous formation of the heteroleptic cadmium(II) bis(terpyridine) complex under ambient conditions can be achieved by a combination of 6,6''-di(2,6-dimethoxylphenyl)-substituted and unsubstituted terpyridine-based ligands. Building on this dynamic heteroleptic complexation, diverse metallo-supramolecular macrocycles and cages were readily assembled in quantitative yields from the predesigned multicomponent systems. The complementary ligation reinforced self-recognition to facilitate the shape-dependent self-sorting of a four-component dynamic library into two well-defined parallelograms. In addition, the subtle lability difference between homoleptic and heteroleptic complexes led to the site-selective CdII -ZnII transmetalation in the Sierpiński triangle. Facile construction of a dodecanuclear tetrahedral metallocage was also realized by using two self-recognizable tritopic building blocks. The photophysical study of the metallo-supramolecules assembled from the d10 metal ions revealed intense ligand-based photoluminescence in solution. The self-assembly strategy described here provides an efficient methodology for building pre-programmable, sophisticated supramolecular architectures furnished with photoactivity.
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Affiliation(s)
- Shih-Yu Wang
- Department of Chemistry, National Taiwan University, No. 1, Sec.4, Roosevelt Rd., Taipei, 10617, Taiwan
| | - Jyun-Yang Huang
- Department of Chemistry, National Taiwan University, No. 1, Sec.4, Roosevelt Rd., Taipei, 10617, Taiwan
| | - Yen-Peng Liang
- Department of Chemistry, National Taiwan University, No. 1, Sec.4, Roosevelt Rd., Taipei, 10617, Taiwan
| | - Yun-Jui He
- Department of Chemistry, National Taiwan University, No. 1, Sec.4, Roosevelt Rd., Taipei, 10617, Taiwan
| | - Yu-Sheng Chen
- Department of Chemistry, National Taiwan University, No. 1, Sec.4, Roosevelt Rd., Taipei, 10617, Taiwan
| | - Yi-Yang Zhan
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
| | - Shuichi Hiraoka
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
| | - Yi-Hung Liu
- Department of Chemistry, National Taiwan University, No. 1, Sec.4, Roosevelt Rd., Taipei, 10617, Taiwan
| | - Shie-Ming Peng
- Department of Chemistry, National Taiwan University, No. 1, Sec.4, Roosevelt Rd., Taipei, 10617, Taiwan
| | - Yi-Tsu Chan
- Department of Chemistry, National Taiwan University, No. 1, Sec.4, Roosevelt Rd., Taipei, 10617, Taiwan
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39
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Abstract
The chemistry of carbeniophosphines and phosphoniocarbenes, which have general structures derived formally from the three-component "carbene/phosphine/positive charge" association, is presented. These two complementary classes of carbon-phosphorus-based ligands, defined by the presence of an inverted cationic coordinating structure (C+ ∼P: vs. P+ ∼C:) have the common purpose of positioning a positive charge in the vicinity of the metal center. Through selected examples, the synthetic methods, coordination properties, and general reactivity of both cationic species is described. Particular emphasis is placed on the influence of the positive charge on the respective chemical behavior of the two classes of compound.
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Affiliation(s)
- Yves Canac
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077, Toulouse Cedex 4, France
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40
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Wang H, Cao H, Zheng JJ, Mathew S, Hosono N, Zhou B, Lyu H, Kusaka S, Jin W, Kitagawa S, Duan J. Finely Controlled Stepwise Engineering of Pore Environments and Mechanistic Elucidation of Water-Stable, Flexible 2D Porous Coordination Polymers. Chemistry 2018; 24:6412-6417. [PMID: 29419938 DOI: 10.1002/chem.201705858] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 02/04/2018] [Indexed: 11/06/2022]
Abstract
Two porous coordination polymers (PCPs) with different topologies (NTU-19: sql and NTU-20: dia) underwent finely controlled, stepwise crystal conversions to yield a common water-stable, flexible 2D framework (NTU-22: kgm). The crystal conversions occurred directly at higher temperature via the 3D intermediate (NTU-21: nbo), which could be observed at lower temperature. The successful isolation of the intermediate product of NTU-21, characterization with in situ PXRD and UV/Vis spectra were combined with DFT calculations to allow an understanding of the dynamic processes at the atomic level. Remarkably, breakthrough experiments demonstrate NTU-22 with integral structural properties allowed significant CO2 /CH4 mixture separation.
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Affiliation(s)
- Haijun Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing, 210009, P.R. China
| | - Haifei Cao
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing, 210009, P.R. China
| | - Jia-Jia Zheng
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University Institute for Advanced Study (KUIAS), Kyoto University, Ushinomiya-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Simon Mathew
- Van't Hoff Institute for Molecular Sciences, Universiteit van Amsterdam, Science Park 904, 1098, XH, Amsterdam, The Netherlands
| | - Nobuhiko Hosono
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University Institute for Advanced Study (KUIAS), Kyoto University, Ushinomiya-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Bihang Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing, 210009, P.R. China
| | - Hongliang Lyu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing, 210009, P.R. China
| | - Shinpei Kusaka
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University Institute for Advanced Study (KUIAS), Kyoto University, Ushinomiya-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Wanqin Jin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing, 210009, P.R. China
| | - Susumu Kitagawa
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University Institute for Advanced Study (KUIAS), Kyoto University, Ushinomiya-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Jingui Duan
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing, 210009, P.R. China
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41
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Verhoeven DGA, van Wiggen MAC, Kwakernaak J, Lutz M, Klein Gebbink RJM, Moret ME. Periodic Trends in the Binding of a Phosphine-Tethered Ketone Ligand to Fe, Co, Ni, and Cu. Chemistry 2018; 24:5163-5172. [PMID: 29077236 DOI: 10.1002/chem.201703254] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Indexed: 11/10/2022]
Abstract
π-Coordinating ligands are commonly found in intermediate structures in homogeneous catalysis, and are gaining interest as supporting ligands for the development of cooperative catalysts. Herein, we systematically investigate the binding of the ketone group, a strongly accepting π ligand, to mid-to-late metals of the first transition series. To this end, the coordination of 2,2'-bis(diphenylphosphino)benzophenone (Ph dpbp), which features a ketone moiety flanked by two strongly binding P-donor groups, to Fe, Co, Ni, and Cu was explored. The ketone moiety does not bind to the metal in MII complexes, whereas MI complexes (Fe, Co, Ni) adopt an η2 (C,O) coordination. A structural and computational investigation of periodic trends in this series was performed. These data suggest that the coordination of the ketone to MI can mostly be described by the resonance extremes of the Dewar-Chatt-Duncanson model, that is, the π complex and the metallaoxacycle extreme, with a possible minor contribution from a ketyl radical resonance structure in the case of the iron complex.
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Affiliation(s)
- Dide G A Verhoeven
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
| | - Maxime A C van Wiggen
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
| | - Joost Kwakernaak
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
| | - Martin Lutz
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, Padualaan 8, 3584 CG, Utrecht, The Netherlands
| | - Robertus J M Klein Gebbink
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
| | - Marc-Etienne Moret
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
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42
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Abstract
Chirality is an essential feature of asymmetric catalysts. This review summarizes asymmetric catalysts that derive their chirality exclusively from stereogenic metal centers. Reported chiral-at-metal catalysts can be divided into two classes, namely, inert metal complexes, in which the metal fulfills a purely structural role, so catalysis is mediated entirely through the ligand sphere, and reactive metal complexes. The latter are particularly appealing because structural simplicity (only achiral ligands) is combined with the prospect of particularly effective asymmetric induction (direct contact of the substrate with the chiral metal center). Challenges and solutions for the design of such reactive stereogenic-only-at-metal asymmetric catalysts are discussed.
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Affiliation(s)
- Lilu Zhang
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043, Marburg, Germany
| | - Eric Meggers
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043, Marburg, Germany
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43
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Kuwabara T, Kurokawa N, Saito M. Reactions of Dilithium Dibenzopentalenides with Cr(CO) 3 (CH 3 CN) 3 : Unexpected Formation of a Cubic Tetramer of an Anionic Hydrodibenzopentalenyl Complex. Chempluschem 2017; 82:1039-1042. [PMID: 31961600 DOI: 10.1002/cplu.201700043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/02/2017] [Indexed: 11/06/2022]
Abstract
To explore the coordination chemistry of dibenzopentalene dianion, reactions of two dilithium dibenzopentalenides having different silyl substituents with Cr(CO)3 (CH3 CN)3 were investigated. The products were unexpected anionic complexes, [Li(Et2 O)]+ [Cr(η5 -9-hydrodibenzopentalenyl)(CO)3 ]- . The proton at the 9-position is derived from Cr(CO)3 (CH3 CN)3 , as evidenced by the use of Cr(CO)3 (CD3 CN)3 . The X-ray diffraction analysis revealed that the chromium is coordinated by an anionic five-membered ring of the pentalene skeleton, and the lithium atom is coordinated by oxygen atoms of the carbonyl groups. The complexes form a dimer or a cage-like tetramer via carbonyl-lithium interactions, depending on the bulk of the silyl groups. The cubic tetramer appears to retain its cage structure in nonpolar solvents such as benzene.
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Affiliation(s)
- Takuya Kuwabara
- Department of Chemistry, Graduate School of Science and Engineering, Saitama University, Shimo-okubo, Sakura-ku, Saitama-city, Saitama, 338-8570, Japan
| | - Nobuaki Kurokawa
- Department of Chemistry, Graduate School of Science and Engineering, Saitama University, Shimo-okubo, Sakura-ku, Saitama-city, Saitama, 338-8570, Japan
| | - Masaichi Saito
- Department of Chemistry, Graduate School of Science and Engineering, Saitama University, Shimo-okubo, Sakura-ku, Saitama-city, Saitama, 338-8570, Japan
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Aman F, Hanif M, Kubanik M, Ashraf A, Söhnel T, Jamieson SMF, Siddiqui WA, Hartinger CG. Anti-Inflammatory Oxicams as Multi-donor Ligand Systems: pH- and Solvent-Dependent Coordination Modes of Meloxicam and Piroxicam to Ru and Os. Chemistry 2017; 23:4893-4902. [PMID: 28198061 DOI: 10.1002/chem.201700263] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Indexed: 11/11/2022]
Abstract
The nitrogen- and sulfur-containing 1,2-benzothiazines meloxicam and piroxicam are widely used as nonsteroidal anti-inflammatory drugs. Intrigued by the presence of multiple donor atoms and therefore potentially rich coordination chemistry, we prepared a series of organometallic Ru and Os compounds with meloxicam and piroxicam featuring either as mono- or bidentate ligand systems. The choice of the solvent and the pH value was identified as the critical parameter to achieve selectively mono- or bidentate coordination. The coordination modes were confirmed experimentally by NMR spectroscopy and single crystal X-ray diffraction analysis. Using DFT calculations, it was established that complexes in which meloxicam acts as a bidentate N,O donor are energetically more favorable than coordination as O,O and S,O donor systems. Since meloxicam and piroxicam derivatives have shown anticancer activity in the past, we aimed to compare the complexes with mono- and bidentate ligands on their in vitro anticancer activity. However, stability studies revealed that only the latter complexes were stable in [D6 ]DMSO/D2 O (5:95) and therefore no direct comparisons could be made. The meloxicam complexes 1 and 2 showed moderate cytotoxicity, whereas the piroxicam derivatives 5 and 6 were hardly active against the utilized cell lines.
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Affiliation(s)
- Farhana Aman
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand.,Department of Chemistry, University of Sargodha, Sargodha, 40100, Pakistan
| | - Muhammad Hanif
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Mario Kubanik
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Adnan Ashraf
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand.,Department of Chemistry, University of Sargodha, Sargodha, 40100, Pakistan
| | - Tilo Söhnel
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Stephen M F Jamieson
- Auckland Cancer Society Research Centre, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | | | - Christian G Hartinger
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
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Wächtler E, Oro LA, Iglesias M, Gerke B, Pöttgen R, Gericke R, Wagler J. Synthesis and Oxidation of a Paddlewheel-Shaped Rhodium/Antimony Complex Featuring Pyridine-2-Thiolate Ligands. Chemistry 2017; 23:3447-3454. [PMID: 28083957 DOI: 10.1002/chem.201605485] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Indexed: 01/11/2023]
Abstract
The paddlewheel-shaped complex [Sb(μ-pyS)4 Rh]2 (1) (pyS- = 2-S-C5 H4 N- ) was synthesized from [Rh(pyS)(cod)]2 (cod=1,5-cyclooctadiene) and Sb(pyS)3 . Upon oxidation with ONMe3 , the complex [(μ-O)Sb(μ-pyS)3 Rh(κ2 -pyS)]2 (2) is formed. Both 1 and 2 form dimers and feature short Rh-Sb bonds and bridging pyS ligands. 121 Sb Mössbauer spectro- scopy and computational studies were employed to elucidate the Rh-Sb bonding in 1 and 2. Both covalent (Rh-Sb, X-type Sb ligand) and dative (Rh→Sb, Z-type; Rh←Sb L-type Sb ligand) interactions have to be considered for the description of their bonding situations.
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Affiliation(s)
- Erik Wächtler
- Institut für Anorganische Chemie, TU Bergakademie Freiberg, Leipziger Straße 29, 09596, Freiberg, Germany.,Departamento Química Inorgánica-ISQCH, Universidad de Zaragoza-CSIC, C/Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Luis A Oro
- Departamento Química Inorgánica-ISQCH, Universidad de Zaragoza-CSIC, C/Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Manuel Iglesias
- Departamento Química Inorgánica-ISQCH, Universidad de Zaragoza-CSIC, C/Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Birgit Gerke
- Institut für Anorganische und Analytische Chemie, WWU Münster, Corrensstraße 30, 48149, Münster, Germany
| | - Rainer Pöttgen
- Institut für Anorganische und Analytische Chemie, WWU Münster, Corrensstraße 30, 48149, Münster, Germany
| | - Robert Gericke
- Institut für Anorganische Chemie, TU Bergakademie Freiberg, Leipziger Straße 29, 09596, Freiberg, Germany
| | - Jörg Wagler
- Institut für Anorganische Chemie, TU Bergakademie Freiberg, Leipziger Straße 29, 09596, Freiberg, Germany
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Dielmann F, Timoshkin A, Piesch M, Balázs G, Scheer M. The Cobalt cyclo-P 4 Sandwich Complex and Its Role in the Formation of Polyphosphorus Compounds. Angew Chem Int Ed Engl 2017; 56:1671-1675. [PMID: 28078794 PMCID: PMC5299486 DOI: 10.1002/anie.201610967] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 11/28/2016] [Indexed: 11/18/2022]
Abstract
A synthetic approach to the sandwich complex [Cp′′′Co(η4‐P4)] (2) containing a cyclo‐P4 ligand as an end‐deck was developed. Complex 2 is the missing homologue in the series of first‐row cyclo‐Pn sandwich complexes, and shows a unique tendency to dimerize in solution to form two isomeric P8 complexes [(Cp′′′Co)2(μ,η4:η2:η1‐P8)] (3 and 4). Reactivity studies indicate that 2 and 3 react with further [Cp′′′Co] fragments to give [(Cp′′′Co)2(μ,η2:η2‐P2)2] (5) and [(Cp′′′Co)3P8] (6), respectively. Furthermore, complexes 2, 3, and 4 thermally decompose forming 5, 6, and the P12 complex [(Cp′′′Co)3P12] (7). DFT calculations on the P4 activation process suggest a η3‐P4 Co complex as the key intermediate in the synthesis of 2 as well as in the formation of larger polyphosphorus complexes via a unique oligomerization pathway.
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Affiliation(s)
- Fabian Dielmann
- Institut für Anorganische Chemie, Universität Regensburg, Universitätsstrasse 31, 93040, Regensburg, Germany
| | - Alexey Timoshkin
- Institute of Chemistry, St. Petersburg State University, Universitetskaya nab. 7/9, 199034, St. Petersburg, Russia
| | - Martin Piesch
- Institut für Anorganische Chemie, Universität Regensburg, Universitätsstrasse 31, 93040, Regensburg, Germany
| | - Gábor Balázs
- Institut für Anorganische Chemie, Universität Regensburg, Universitätsstrasse 31, 93040, Regensburg, Germany
| | - Manfred Scheer
- Institut für Anorganische Chemie, Universität Regensburg, Universitätsstrasse 31, 93040, Regensburg, Germany
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Abstract
Given the importance of Fe-NO complexes in both human biology and the global nitrogen cycle, there has been interest in understanding their diverse electronic structures. Herein a redox series of isolable iron nitrosyl complexes stabilized by a tris(phosphine)borane (TPB) ligand is described. These structurally characterized iron nitrosyl complexes reside in the following highly reduced Enemark-Feltham numbers: {FeNO}(8) , {FeNO}(9) , and {FeNO}(10) . These {FeNO}(8-10) compounds are each low-spin, and feature linear yet strongly activated nitric oxide ligands. Use of Mössbauer, EPR, NMR, UV/Vis, and IR spectroscopy, in conjunction with DFT calculations, provides insight into the electronic structures of this uncommon redox series of iron nitrosyl complexes. In particular, the data collectively suggest that {TPBFeNO}(8-10) are all remarkably covalent. This covalency is likely responsible for the stability of this system across three highly reduced redox states that correlate with unusually high Enemark-Feltham numbers.
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Affiliation(s)
- Matthew J Chalkley
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA, 91125, USA
| | - Jonas C Peters
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA, 91125, USA.
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Abstract
Organometallic chemistry can be considered as a wide area of knowledge that combines concepts of classic organic chemistry, that is, based essentially on carbon, with molecular inorganic chemistry, especially with coordination compounds. Transition-metal methyl complexes probably represent the simplest and most fundamental way to view how these two major areas of chemistry combine and merge into novel species with intriguing features in terms of reactivity, structure, and bonding. Citing more than 500 bibliographic references, this review aims to offer a concise view of recent advances in the field of transition-metal complexes containing M-CH3 fragments. Taking into account the impressive amount of data that are continuously provided by organometallic chemists in this area, this review is mainly focused on results of the last five years. After a panoramic overview on M-CH3 compounds of Groups 3 to 11, which includes the most recent landmark findings in this area, two further sections are dedicated to methyl-bridged complexes and reactivity.
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Affiliation(s)
- Jesús Campos
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Joaquín López-Serrano
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química, Avanzada (ORFEO-CINQA), Universidad de Sevilla and Consejo Superior de Investigaciones Cientificas (CSIC), Avenida Américo Vespucio 49, 41092, Sevilla, Spain
| | - Riccardo Peloso
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química, Avanzada (ORFEO-CINQA), Universidad de Sevilla and Consejo Superior de Investigaciones Cientificas (CSIC), Avenida Américo Vespucio 49, 41092, Sevilla, Spain
| | - Ernesto Carmona
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química, Avanzada (ORFEO-CINQA), Universidad de Sevilla and Consejo Superior de Investigaciones Cientificas (CSIC), Avenida Américo Vespucio 49, 41092, Sevilla, Spain.
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Shi Q, Yan L, Chan T, Jing C. Arsenic Adsorption on Lanthanum-Impregnated Activated Alumina: Spectroscopic and DFT Study. ACS Appl Mater Interfaces 2015; 7:26735-26741. [PMID: 26565426 DOI: 10.1021/acsami.5b08730] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Rare earth-modified adsorbents (REMAs) have been widely used to remove oxyanion pollutants from water, including arsenic (As). However, the molecular-level structural information and reactions at the liquid/solid interface are still murky, which limits the design of applicable REMAs. Herein, a lanthanum-impregnated activated alumina (LAA) was synthesized as a representative REMA, and its As uptake mechanisms were explored using multiple complementary characterization techniques. Our adsorption experiments showed that LAA exhibited 2-3 times higher As adsorption capacity than AA. In contrast to the bidentate configuration formed on most metal oxide surfaces, our EXAFS and DFT results suggest that As(III) and As(V) form monodentate surface complexes on LAA through As-O-La coordinative bonding. In situ flow cell ATR-FTIR observed a strong dependence of As-O peak positions on pH, which could be interpreted as the change in the fractions of As(V) surface complexes with zero- to double-protonation on LAA, AA, and LaOOH. As(V) on LAA existed as singly and doubly protonated surface species, and the pKa of transition from double to single protonation (∼5.8) was lower than that for its soluble counterpart (6.97). The surface reaction and structural configuration were incorporated in a CD-MUSIC model to satisfactorily predict macroscopic As adsorption behaviors. The insights gained from the molecular-level reactions shed light on the design and application of REMAs in environmental remediation for As and its structural analogues.
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Affiliation(s)
- Qiantao Shi
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
| | - Li Yan
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
| | - Tingshan Chan
- National Synchrotron Radiation Research Center , 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan
| | - Chuanyong Jing
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
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50
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Thomsen MK, Dange D, Jones C, Overgaard J. Chemical bonding and electronic localization in a Ga(I) amide. Chemistry 2015; 21:14460-70. [PMID: 26296814 DOI: 10.1002/chem.201500760] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 07/08/2015] [Indexed: 11/07/2022]
Abstract
The electron density in a one-coordinate [Ga(I) N(SiMe3 )R] complex has been determined from ab initio calculations and multipole modeling of 90 K X-ray data. The topologies of the Laplacian distribution and the ELI-D match a situation having an sp(3) -hybridized nitrogen with a tetrahedral arrangement of two single σ-bonds (to carbon and silicon) and two lone pairs pointing towards gallium in a scissor-grasping fashion. The analysis of the Laplacian distribution furthermore reveals a ligand-induced charge concentration (LICC) in the outer core of gallium oriented directly towards the nitrogen atom, and thus in between the two lone pairs. These observations might suggest that the trigonal planar nitrogen geometry result from a dative GaN bond, in which the roles of the metal and the ligand have been reversed with respect to a "standard" metal-ligand interaction, that is, the metal is here electron-donating. The ELI-D reveals a diffuse and directional lone pair on gallium, suggesting that this complex could serve as a σ-donor.
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Affiliation(s)
- Maja K Thomsen
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus (Denmark)
| | - Deepak Dange
- School of Chemistry, Monash University, Melbourne, VIC, 3800 (Australia)
| | - Cameron Jones
- School of Chemistry, Monash University, Melbourne, VIC, 3800 (Australia)
| | - Jacob Overgaard
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus (Denmark).
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