1
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Helling C, Wilson DJD, Jones C. Monomeric Two-coordinate Beryllium Imido and Boryloxide Complexes Featuring Be-N and Be-O Triple Bonds. J Am Chem Soc 2025; 147:16620-16629. [PMID: 40312141 DOI: 10.1021/jacs.5c04320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2025]
Abstract
The 2p elements possess a unique propensity to participate in multiple bonding. Realization of multiple bonding involving the 2s elements, however, is challenging and remains exceedingly rare. In this contribution, we present the syntheses, detailed characterization, and molecular structures of heteroleptic beryllium imido and boryloxide complexes of the type [(HCNDip)2YXBeAr(OEt2)n]m (Y,X = C,N or B,O; n = 0, 1; m = 1, 2; Dip = 2,6-iPr2C6H3) by salt metathesis and arene elimination approaches. Systematic adjustment of the steric demand of the aryl substituent resulted in the isolation of monomeric, two-coordinate beryllium imido and boryloxide complexes, (HCNDip)2CNBeTip (9, Tip = 2,4,6-iPr3C6H2) and (HCNDip)2BOBeArDip (12, ArDip = 2,6-Dip2C6H3), containing virtually linear C-N-Be-C and B-O-Be-C arrangements and extremely short Be-N (1.434(2) Å, 1.437(3) Å) and Be-O (1.4035(14) Å) bonds, respectively. These were shown by in-depth computational electronic structure and bonding analyses to possess unprecedented triple bond character. The Be-O bond in 12 constitutes the first s-block metal-oxygen multiple bond.
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Affiliation(s)
- Christoph Helling
- School of Chemistry, Monash University, PO Box 23, Melbourne, VIC 3800, Australia
| | - David J D Wilson
- Department of Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086, Australia
| | - Cameron Jones
- School of Chemistry, Monash University, PO Box 23, Melbourne, VIC 3800, Australia
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2
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Morasch M, Vilpas T, Patel N, Maurer J, Thum S, Schmidt MA, Langer J, Harder S. Dinitrogen Activation with Low-Valent Strontium. Angew Chem Int Ed Engl 2025:e202506989. [PMID: 40317582 DOI: 10.1002/anie.202506989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2025] [Revised: 04/17/2025] [Accepted: 04/29/2025] [Indexed: 05/07/2025]
Abstract
DFT calculations on β-diketiminate (BDI) complexes with the full series of alkaline-earth (Ae) metals show that (BDI)AeAe(BDI) complexes of the heavier Ae metals (Ca, Sr, Ba) have long weak Ae─Ae bonds that are prone to homolytic bond cleavage. However, isolation of (BDI)Sr(μ-N2)Sr(BDI) with a side-on bridging N2 2- dianion should thermodynamically be feasible. Attempts to stabilize such a complex with the super bulky BDI* ligand failed (BDI* = HC[(Me)C = N-DIPeP]2, DIPeP = 2,6-Et2CH-phenyl). First, N2 fixation with a Sr complex was enabled by a heterobimetallic approach. Reduction of (DIPePNN)Sr with potassium gave (DIPePNN)2Sr2K2(N2) (6-Sr); DIPePNN = DIPePN-Si(Me)2CH2CH2Si(Me)2-NDIPeP. A similar Ca product was also isolated (6-Ca). Crystal structures reveal a N2 2- anion with side-on bonding to Ae2+ and end-on coordination to K+. DFT calculations and Atoms-In-Molecules analyses show mainly ionic bonding. Both 6-Ae complexes are synthons for hitherto unknown (BDI*)AeAe(BDI*) (Ae = Ca, Sr) and react by releasing N2 and two electrons. Although surprisingly stable in benzene, the reduction of I2 and H2 is facile. Fast reaction with Teflon led to formation of crystalline [(DIPePNN)SrKF]2 (7), which is labile and decomposed to KF and (DIPePNN)Sr. Latter reactivity underscores potential use of 6-Ae complexes as very strong, hydrocarbon-soluble reducing agents.
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Affiliation(s)
- Michael Morasch
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Timothy Vilpas
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Neha Patel
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Johannes Maurer
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Stefan Thum
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Marcel A Schmidt
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Jens Langer
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Sjoerd Harder
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
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3
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Berthold C, Lochte MH, Buchner MR. Transmetalation From Boron to Beryllium in Phosphorus-Based Scorpionate Complexes. Chemistry 2025; 31:e202500673. [PMID: 40084502 PMCID: PMC12043030 DOI: 10.1002/chem.202500673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2025] [Revised: 03/12/2025] [Accepted: 03/14/2025] [Indexed: 03/16/2025]
Abstract
Investigation of tris(di-iso-propylphosphanylmethyl)phenylborate ([TP(iPr)]-) organo-beryllium complexes [TP(iPr)]BeR with R = Ph, nBu, Cp, Cp* revealed transmetalation of [CH2P(iPr)2]- groups from boron onto beryllium. This reaction is caused by partial dissociation of the scorpionate, which can be triggered through steric overcrowding of the beryllium atom or reducing the ligand beryllium bond strength through oxidation of the phosphorus atoms with selenium. Oxidation with oxygen or sulfur results in the formation of stable phosphine oxide and sulfide scorpionates.
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Affiliation(s)
| | - Mark H. Lochte
- Fachbereich ChemiePhilipps‐Universität Marburg35043MarburgGermany
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4
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Boronski JT, Crumpton AE, Struijs JJC, Aldridge S. Methane Beryllation Catalyzed by a Base Metal Complex. J Am Chem Soc 2025; 147:10073-10077. [PMID: 40068010 PMCID: PMC11951138 DOI: 10.1021/jacs.5c02179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2025] [Revised: 03/06/2025] [Accepted: 03/07/2025] [Indexed: 03/27/2025]
Abstract
The homogeneous catalytic functionalization of methane is extremely challenging due to the relative nonpolarity and high C-H bond strength of this hydrocarbon. Here, using catalytic quantities (10 mol %) of CpMn(CO)3 or Cp*Re(CO)3, the conversion of methane and benzene C-H bonds to C-Be and H-Be bonds by CpBeBeCp has been achieved under photochemical conditions. Possible intermediates in the beryllation reactions─trans-bis(beryllyl)-manganese and -rhenium complexes─were also isolated. Quantum chemical calculations indicate that the inherent properties of the beryllyl ligands─which are powerfully σ-donating and feature highly Lewis acidic beryllium centers─are decisive in enabling methane functionalization by these systems.
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Affiliation(s)
- Josef T. Boronski
- Molecular
Sciences Research Hub, Department of Chemistry, Imperial College London, 82 Wood Lane, White City, London W12 0BZ, U.K.
| | - Agamemnon E. Crumpton
- Chemistry
Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K.
| | - Job J. C. Struijs
- Chemistry
Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K.
| | - Simon Aldridge
- Chemistry
Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K.
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5
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Bischoff IA, Morgenstern B, Zimmer M, Schäfer A. Heavy Pentaisopropylcyclopentadienyltriylenes and their Heterobimetallic Complexes. Angew Chem Int Ed Engl 2025; 64:e202419688. [PMID: 39541093 DOI: 10.1002/anie.202419688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2024] [Revised: 11/05/2024] [Accepted: 11/12/2024] [Indexed: 11/16/2024]
Abstract
A series of triylenes of the heavy group 13 elements gallium, indium and thallium, carrying the pentaisopropylcyclopentadienyl ligand is reported. The compounds were characterized in solution and in the solid-state and their donor ligand properties in heterobimetallic complexes were investigated, whereby a series of tungsten carbonyl complexes was isolated. Furthermore, a new synthetic route towards a previously described lithium-aluminum heterobimetallic dimetallocene is reported, which also enabled the isolation of a heterobimetallic polydecker of lithium and gallium.
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Affiliation(s)
- Inga-Alexandra Bischoff
- Department of Chemistry; Faculty of Natural Sciences and Technology, Saarland University Campus Saarbrücken, 66123, Saarbrücken, Saarland, Germany
| | - Bernd Morgenstern
- Department of Chemistry; Faculty of Natural Sciences and Technology, Saarland University Campus Saarbrücken, 66123, Saarbrücken, Saarland, Germany
| | - Michael Zimmer
- Department of Chemistry; Faculty of Natural Sciences and Technology, Saarland University Campus Saarbrücken, 66123, Saarbrücken, Saarland, Germany
| | - André Schäfer
- Department of Chemistry; Faculty of Natural Sciences and Technology, Saarland University Campus Saarbrücken, 66123, Saarbrücken, Saarland, Germany
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6
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Jackson RA, Evans NJ, Babula DJ, Horsley Downie TM, Charman RSC, Neale SE, Mahon MF, Liptrot DJ. Nucleophilicity at copper(-I) in a compound with a Cu-Mg bond. Nat Commun 2025; 16:1101. [PMID: 39875432 PMCID: PMC11775243 DOI: 10.1038/s41467-025-56544-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2024] [Accepted: 01/21/2025] [Indexed: 01/30/2025] Open
Abstract
Copper is ubiquitous as a structural material, and as a reagent in (bio)chemical transformations. A vast number of chemical reactions rely on the near-inevitable preference of copper for positive oxidation states to make useful compounds. Here we show this electronic paradigm can be subverted in a stable compound with a copper-magnesium bond, which conforms to the formal oxidation state of Cu(-I). The Cu-Mg bond is synthesized by the reaction of an N-heterocyclic carbene (NHC) ligated copper alkoxide with a dimeric magnesium(I) compound. Its identity is confirmed by single-crystal X-ray structural analysis and NMR spectroscopy, and computational investigations provide data consistent with a high charge density at copper. The Cu-Mg bond acts as a source of the cupride anion, transferring the NHC-copper fragment to electrophilic s-, p-, and d-block atoms to make known and new copper-containing compounds.
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Affiliation(s)
- Ross A Jackson
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | | | - Dawid J Babula
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
- Institute for Sustainability, University of Bath, Bath, BA2 7AY, UK
| | | | - Rex S C Charman
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | - Samuel E Neale
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | - Mary F Mahon
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | - David J Liptrot
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK.
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7
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Boronski JT, Crumpton AE, Aldridge S. A Crystalline NiX 6 Complex. J Am Chem Soc 2024; 146:35208-35215. [PMID: 39668527 DOI: 10.1021/jacs.4c12125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2024]
Abstract
High-valent nickel species are implicated as intermediates in industrially relevant chemical transformations and in the catalytic cycles of metalloenzymes. Although a small number of tetravalent NiX4 complexes have been crystallographically characterized, higher nickel valence states have not been identified. Here we report a stable, crystalline NiX6 complex, Ni(BeCp)6 (1; cyclopentadienyl anion (Cp)), formed by the insertion of zerovalent nickel into three Be-Be bonds. This 16-electron species features an inverted ligand field, is diamagnetic, and exhibits C3v symmetry, on account of the lifting of Ni 4p-orbital degeneracy in this molecular geometry. Single-crystal X-ray diffraction and quantum chemical calculations both reveal a toroidal band of electron density perpendicular to the C3 axis of the complex, which may be attributed to delocalized, multicenter aromatic NiBe6 bonding.
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Affiliation(s)
- Josef T Boronski
- Chemistry Research Laboratory, Department of Chemistry, Oxford OX1 3TA, U.K
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, 82 Wood Lane, White City, London W12 7TA, U.K
| | | | - Simon Aldridge
- Chemistry Research Laboratory, Department of Chemistry, Oxford OX1 3TA, U.K
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8
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Berthold C, Hoß G, Lochte MH, Buchner MR. Neutral Phosphorus-Based Beryllium Scorpionate Complexes as Spectroscopic Probes for Base Strength and Electron Donation. Inorg Chem 2024; 63:24392-24399. [PMID: 39648439 DOI: 10.1021/acs.inorgchem.4c04565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/10/2024]
Abstract
The synthesis and properties of tris(diisopropylphosphanylmethyl)phenylborate ([TP(iPr)]-) beryllium complexes [TP(iPr)]BeL with L = Cl, Br, I, CN, SCN, OCN, N3, and CF3SO3 are described. In these compounds, the 1JPBe NMR coupling constant can be used as a sensitive probe for the basicity and electron-donating properties of the L- anions in solution.
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Affiliation(s)
| | - Giuliana Hoß
- Fachbereich Chemie, Philipps-Universität Marburg, 35043 Marburg, Germany
| | - Mark H Lochte
- Fachbereich Chemie, Philipps-Universität Marburg, 35043 Marburg, Germany
| | - Magnus R Buchner
- Fachbereich Chemie, Philipps-Universität Marburg, 35043 Marburg, Germany
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9
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Shen Y, Roselló Y, Abella L, Qiu J, Du X, Meng Q, Zheng L, Cao Z, He Z, Poblet JM, Echegoyen L, Sun L, Rodríguez-Fortea A, Chen N. Fluoride Clusterfullerenes: Tuning Metal-Metal Bonding and Magnetic Properties via Single Fluorine Atom Doping. J Am Chem Soc 2024; 146:34924-34933. [PMID: 39644247 DOI: 10.1021/jacs.4c14430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2024]
Abstract
Endohedral fullerenes are known for their exceptional ability to host metal clusters that contain unique bonding motifs. In this study, we report a facile strategy to synthesize a new family of clusterfullerenes, fluoride clusterfullerenes (FCFs). This work demonstrates that actinides and rare earth metals as well as alkaline earth metals can be encapsulated within a variety of fullerene cages, and these fullerenes can be obtained in their pristine form without additional functionalization methods. Notably, Th2F@Ih(7)-C80 and CaScF@Cs(6)-C82 were isolated and their molecular structures and magnetic properties were characterized by X-ray single-crystal diffraction and multiple spectroscopic techniques as well as DFT calculations. These findings reveal that the unique internal addition of a single fluorine atom significantly alters the metal-metal bonding interactions of Th-Th and Ca-Sc. While Th2@Ih(7)-C80 hosts a σ2 Th-Th bond, an unprecedented actinide-actinide (Th-Th) single electron metal-metal bond is formed inside Th2F@Ih(7)-C80 upon the internal addition of fluoride. Similarly, while a Ca-Sc single electron bond exists in CaSc@Cs(6)-C82, which exhibits excellent molecular qubit properties, the addition of fluoride transforms the compound into a singlet. The present study not only highlights the successful synthesis of a novel family of FCFs, which will likely be an extensive family, it also shows that fluorine doping can induce novel metal-metal bonding motifs leading to potentially intriguing magnetic properties.
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Affiliation(s)
- Yi Shen
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P. R. China
| | - Yannick Roselló
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, 43007 Tarragona, Spain
| | - Laura Abella
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, 43007 Tarragona, Spain
| | - Jiawei Qiu
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P. R. China
| | - Xiya Du
- Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, Hangzhou, Zhejiang 310030, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Qingyu Meng
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P. R. China
| | - Lihao Zheng
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P. R. China
| | - Zhengkai Cao
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P. R. China
| | - Zhiwen He
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P. R. China
| | - Josep M Poblet
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, 43007 Tarragona, Spain
| | - Luis Echegoyen
- Department of Chemistry, University of Texas at El Paso, El Paso, Texas 79968, United States
- Institut Català d'Investigació Química, 43007 Tarragona, Catalonia, Spain
| | - Lei Sun
- Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, Hangzhou, Zhejiang 310030, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
- Key Laboratory for Quantum Materials of Zhejiang Province, Department of Physics, School of Science, Westlake University, Hangzhou, Zhejiang 310030, China
| | - Antonio Rodríguez-Fortea
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, 43007 Tarragona, Spain
| | - Ning Chen
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P. R. China
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10
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Griffin LP, Aldridge S. Zinc borylation and reduction by a diborane(4) species via B-O bond formation. Chem Sci 2024; 15:19577-19582. [PMID: 39568930 PMCID: PMC11575557 DOI: 10.1039/d4sc06389a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2024] [Accepted: 11/01/2024] [Indexed: 11/22/2024] Open
Abstract
We report a convenient synthesis of the zinc-boryl complex (NacnacMes)ZnBpin under mild conditions via formal disproportionation of bis(pinacolato)diboron(4), aided thermodynamically by B-O bond formation. This species can be isolated both base-free and as the DMAP adduct (NacnacMes)Zn(DMAP)Bpin and crystallographically characterised in the latter form. Onward reactivity of the base free zinc boryl complex with CO2 occurs reductively, yielding further B-O bonds as well as CO gas. The strength of this driving force can then be harnessed in the reaction between (NacnacMes)ZnBpin and a Zn-O bonded species (NacnacMes)ZnOB{(NDippCH)2}, which yields the metal-metal bonded dimer [(NacnacMes)Zn]2, the overall formation of which utilizes a diboron(4) species as the stoichiometric reductant of Zn(ii) to Zn(i).
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Affiliation(s)
- Liam P Griffin
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Simon Aldridge
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford South Parks Road Oxford OX1 3QR UK
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11
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Czernetzki C, Arrowsmith M, Jürgensen M, Hagspiel S, Braunschweig H. Synthesis and structures of molecular beryllium Grignard analogues featuring terminal and bridging pseudohalides. Dalton Trans 2024; 53:18296-18303. [PMID: 39450448 DOI: 10.1039/d4dt02457e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2024]
Abstract
The carbene-stabilised beryllium Grignards [(CAAC)BeBrR] (R = CAACH 1a, Dur 1b; CAAC/H = 1-(2,6-diisopropylphenyl)-2,2,4,4-tetramethylpyrrolidin-2-yl/idene; Dur = 2,3,5,6-tetramethylphenyl) undergo salt metathesis with various pseudohalide salt precursors. Whereas with [NaNCS] the thiocyanato Grignards [(CAAC)Be(NCS)R] (R = CAACH 2a, Dur 2b) are obtained selectively, salt metatheses with [Na(OCP)(dioxane)2.3] and [K(OCN)] are fraught with side reactions, in particular scrambling of both neutral and anionic ligands, leading to complex product mixtures, from which the first examples of beryllium phosphaethynolate Grignards [(thf)2(CAACH)Be(OCP)] (3) and [(CAAC)Be(OCP)R] (R = CAACH 4a, Dur 4b), as well as the isocyanate-bridged hexamer [(CAAC)BrBe(1,3-μ-OCN)]6 (7) were determined as the main products. The complexity of possible side reactions is seen in complex 5, a byproduct of the salt metathesis of 1b with [Na(OCP)(dioxane)2.3], which hints at radical redox processes, OCP homocoupling, OCP coupling with CAAC, as well as OCP insertion into the Be-R bond. Finally, the unstable, tetrameric cyano-bridged beryllium Grignard [(thf)(CAACH)Be(1,2-μ-CN)] (8) was obtained by salt metathesis of 1a with [Na/KSeCN] alongside one equiv. CAACSe. The new complexes were characterised by heteronuclear NMR and IR spectroscopy, as well X-ray crystallography.
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Affiliation(s)
- Corinna Czernetzki
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Merle Arrowsmith
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Malte Jürgensen
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Stephan Hagspiel
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
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12
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Bowles AWJ, Liu Y, Stevens MP, Ortu F. Heavy Alkaline Earth Cyclic (Alkyl)(Amino)Carbene Complexes Supported by Aryl-Silyl Amides. Inorg Chem 2024; 63:22061-22073. [PMID: 39505707 DOI: 10.1021/acs.inorgchem.4c03494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2024]
Abstract
A series of 8 trigonal planar, heavy alkaline earth (AE = Ca-Ba) metal complexes containing cyclic (alkyl)(amino)carbene (CAAC) ligands were prepared from AE bis(amide) species. Complexation can be achieved by first generating the free carbene in situ or by direct addition of the free carbene, with the former route giving rise to unexpected mixed-amide AE complexes. The frontier molecular orbitals of the highly equatorial, 3-coordinate AE-CAAC species were also probed computationally, revealing the lowest unoccupied molecular orbital (LUMO) consisting predominantly of the π* system located on the carbene ligand.
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Affiliation(s)
- Alex W J Bowles
- School of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, U.K
| | - Yu Liu
- School of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, U.K
| | - Matthew P Stevens
- School of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, U.K
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
| | - Fabrizio Ortu
- School of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, U.K
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13
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Bowles AW, Quirk JA, Liu Y, Morritt GH, Freitag M, Whitehead GFS, Woodward AW, Brookfield A, Goodwin CAP, Collison D, Tuna F, McMullin CL, Dawson JA, Lu E, Ortu F. Mechanochemical Synthesis, Characterization and Reactivity of a Room Temperature Stable Calcium Electride. J Am Chem Soc 2024; 146:28914-28924. [PMID: 39377174 PMCID: PMC11503782 DOI: 10.1021/jacs.4c09408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2024] [Revised: 09/23/2024] [Accepted: 09/24/2024] [Indexed: 10/09/2024]
Abstract
A new calcium-based Room temperature Stable Electride (RoSE), K[{Ca[N(Mes)(SiMe3)]3(e-)}2K3] (2), is successfully synthesized from the reaction of a calcium tris-amide, [Ca{N(Mes)(SiMe3)}3K] (1) (Mes = 2,4,6-trimethylphenyl), with potassium under mechanochemical treatment. The dimeric structure of K[{Ca[N(Mes)(SiMe3)]3(e-)}2K3] is calculated using ab initio random structure searching (AIRSS) methods. This shows the existence of highly localized anionic electrons (e-) and suggests poor electrical conductance, as confirmed via electroconductivity measurements. The two anionic electrons in 2 are strongly antiferromagnetically coupled, thus in agreement with the largely diamagnetic response from magnetometry. Reaction of 2 with pyridine affords 4,4'-bipyridine, while reaction with benzene gives C-H activation and formation of a calcium hydride complex, [K(η6-C6H6)4][{Ca[N(Mes)(SiMe3)](H)}2K3] (3). Computational DFT analysis reveals the crucial role played by the ligand framework in the stabilization of this new Ca-hydride complex.
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Affiliation(s)
- Alex W.
J. Bowles
- School
of Chemistry, University of Leicester, University Road, Leicester, LE1 7RH, U.K.
| | - James A. Quirk
- Chemistry
− School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU, U.K.
| | - Yu Liu
- School
of Chemistry, University of Leicester, University Road, Leicester, LE1 7RH, U.K.
| | - George H. Morritt
- School
of Mathematics, Statistics, and Physics, Newcastle University, Newcastle
upon Tyne, NE1 7RU, U.K.
| | - Marina Freitag
- Chemistry
− School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU, U.K.
| | | | - Adam W. Woodward
- Department
of Chemistry, The University of Manchester, Manchester, M13 9PL, U.K.
| | - Adam Brookfield
- Department
of Chemistry and Photon Science Institute, The University of Manchester, Manchester, M13 9PL, U.K.
| | - Conrad A. P. Goodwin
- Department
of Chemistry, The University of Manchester, Manchester, M13 9PL, U.K.
| | - David Collison
- Department
of Chemistry and Photon Science Institute, The University of Manchester, Manchester, M13 9PL, U.K.
| | - Floriana Tuna
- Department
of Chemistry and Photon Science Institute, The University of Manchester, Manchester, M13 9PL, U.K.
| | - Claire L. McMullin
- Department
of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, U.K.
| | - James A. Dawson
- Chemistry
− School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU, U.K.
| | - Erli Lu
- School
of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT, U.K.
| | - Fabrizio Ortu
- School
of Chemistry, University of Leicester, University Road, Leicester, LE1 7RH, U.K.
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14
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Bekiş DF, Thomas-Hargreaves LR, Ivlev SI, Buchner MR. Multinuclear beryllium amide and imide complexes: structure, properties and bonding. Dalton Trans 2024; 53:15551-15564. [PMID: 39229744 DOI: 10.1039/d4dt02269f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/05/2024]
Abstract
The beryllium amide and imide complexes [Be(HNMes)2]3, [(py)2Be(HNMes)2], [Be(HNDipp)2]2, [Be(NPh2)(μ2-HNDipp)]2 and [Be(NCPh2)2]3 have been prepared and characterised with NMR and IR spectroscopy as well as single crystal X-ray diffraction. Analysis of the localised molecular orbitals (LMOs) and intrinsic atomic orbital (IAO) atomic charges in the framework of the intrinsic bond orbital (IBO) localization method revealed a covalent bonding network consisting of 2-electron-2-centre and 2-electron-3-centre σ bonds, in which one electron pair of the anionic N-donor ligands is involved. The electron deficiency at the beryllium atoms is partially compensated through additional electron donation from the lone pair at the nitrogen atoms.
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Affiliation(s)
- Deniz F Bekiş
- Anorganische Chemie, Nachwuchsgruppe Hauptgruppenmetallchemie, Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany.
| | - Lewis R Thomas-Hargreaves
- Anorganische Chemie, Nachwuchsgruppe Hauptgruppenmetallchemie, Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany.
| | - Sergei I Ivlev
- Anorganische Chemie, Nachwuchsgruppe Hauptgruppenmetallchemie, Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany.
| | - Magnus R Buchner
- Anorganische Chemie, Nachwuchsgruppe Hauptgruppenmetallchemie, Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany.
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15
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Buchner MR, Müller M, Ivlev SI. Multinuclear Beryllium Chloro Carboxylates. Inorg Chem 2024. [PMID: 39253792 DOI: 10.1021/acs.inorgchem.4c03103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/11/2024]
Abstract
Reaction of 1 equiv of BeCl2 with mesityl (Mes) or o-tolyl (o-Tol) carboxylic acid in benzene gives hexanuclear heterocyles [BeCl(MesCO2)]6 and [BeCl(o-TolCO2)]6, respectively. Small amounts of the oxocarboxylates [Be4O(MesCO2)6] and [Be4O(o-TolCO2)6] are also formed. If chloroform is used as the solvent, a mixture of these complexes together with the unprecedented tertranuclear cage compounds [Be4Cl2(MesCO2)6] and [Be4Cl2(o-TolCO2)6] is obtained.
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Affiliation(s)
- Magnus R Buchner
- Fachbereich Chemie, Philipps-Universität Marburg, 35043 Marburg, Germany
| | - Matthias Müller
- Fachbereich Chemie, Philipps-Universität Marburg, 35043 Marburg, Germany
| | - Sergei I Ivlev
- Fachbereich Chemie, Philipps-Universität Marburg, 35043 Marburg, Germany
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16
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Gosch MA, Wilson DJD. Prediction of Covalent Metal-Metal Bonding in Cp-M-M'-Nacnac Complexes of Group 2 and 12 Metals (Be, Mg, Ca, Zn, Cd, Hg). Chemistry 2024; 30:e202402118. [PMID: 38935331 DOI: 10.1002/chem.202402118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 06/27/2024] [Accepted: 06/27/2024] [Indexed: 06/28/2024]
Abstract
Bimetallic CpMM'Nacnac molecules with group 2 and 12 metals (M=Be, Mg, Ca, Zn, Cd, Hg) that contain novel metal-metal bonding have been investigated in a theoretical study of their molecular and electronic structure, thermodynamic stability, and metal-metal bonding. In all cases the metal-metal bonds are characterized as electron-sharing covalent single bonds from natural bond orbital (NBO) and energy-decomposition analysis with natural orbitals of chemical valence (EDA-NOCV) analysis. The sum of [MM'] charges is relatively constant, with all complexes exhibiting a [MM']2+ core. Quantum theory of atoms in molecules (QTAIM) analysis indicates the presence of non-nuclear attractors (NNA) in the metal-metal bonds of the BeBe, MgMg, and CaCa complexes. There is substantial electron density (0.75-1.33 e) associated with the NNAs, which indicates that these metal-metal bonds, while classified as covalent electron-sharing bonds, retain significant metallic character that can be associated with reducing reactivity of the complex. The predicted stability of these complexes, combined with their novel covalent metal-metal bonding and potential as reducing agents, make them appealing targets for the synthesis of new metal-metal bonds.
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Affiliation(s)
- Matthew A Gosch
- Department of Chemistry, La Trobe Institute for Molecular Science (LIMS), La Trobe University, Melbourne, Victoria, 3086, Australia
| | - David J D Wilson
- Department of Chemistry, La Trobe Institute for Molecular Science (LIMS), La Trobe University, Melbourne, Victoria, 3086, Australia
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17
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Qiu J, Abella L, Du X, Cao Z, He Z, Meng Q, Yan Y, Poblet JM, Sun L, Rodríguez-Fortea A, Chen N. CaY@C 2n: Exploring Molecular Qubits with Ca-Y Metal-Metal Bonds. J Am Chem Soc 2024; 146:24310-24319. [PMID: 39165005 PMCID: PMC11555672 DOI: 10.1021/jacs.4c04720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 08/08/2024] [Accepted: 08/09/2024] [Indexed: 08/22/2024]
Abstract
Metal-metal bonding is crucial in chemistry for advancing our understanding of the fundamental aspects of chemical bonds. Metal-metal bonds based on alkaline-earth (Ae) elements, especially the heavier Ae elements (Ca, Sr, and Ba), are rarely reported due to their high electropositivity. Herein, we report two heteronuclear di-EMFs CaY@Cs(6)-C82 and CaY@C2v(5)-C80, which contain unprecedented single-electron Ca-Y metal-metal bonds. These compounds were characterized by single-crystal X-ray crystallography, electron paramagnetic resonance (EPR) spectroscopy, and DFT calculations. The crystallographic study of CaY@Cs(6)-C82 shows that Ca and Y are successfully encapsulated into the carbon cage with a Ca-Y distance of 3.691 Å. The CW-EPR study of both CaY@Cs(6)-C82 and CaY@C2v(5)-C80 exhibits a doublet, suggesting the presence of an unpaired electron located between Ca and Y. The combined experimental and theoretical results confirm the presence of a Ca-Y single-electron metal-metal bond with substantial covalent interaction, attributed to significant overlap between the 4s4p orbitals of Ca and the 5s5p4d orbitals of Y. Furthermore, pulse EPR spectroscopy was used to investigate the quantum coherence of the electron spin within this bond. The unpaired electron, characterized by its s orbital nature, is effectively protected by the carbon cage, resulting in efficient suppression of both spin-lattice relaxation and decoherence. CaY@Cs(6)-C82 behaves as an electron spin qubit, displaying a maximum decoherence time of 7.74 μs at 40 K. This study reveals an unprecedented Ae-rare-earth metal-metal bond stabilized by the fullerene cages and elucidates the molecular qubit properties stemming from their unique bonding character, highlighting their potential in quantum information processing applications.
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Affiliation(s)
- Jiawei Qiu
- College
of Chemistry, Chemical Engineering, and Materials Science and State
Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P.R. China
| | - Laura Abella
- Departament
de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, Tarragona 43007, Spain
| | - Xiya Du
- Department
of Chemistry, School of Science and Research Center for Industries
of the Future, Westlake University, Hangzhou, Zhejiang Province 310030, China
- Institute
of Natural Sciences, Westlake Institute
for Advanced Study, Hangzhou, Zhejiang Province 310024, China
| | - Zhengkai Cao
- College
of Chemistry, Chemical Engineering, and Materials Science and State
Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P.R. China
| | - Zhiwen He
- College
of Chemistry, Chemical Engineering, and Materials Science and State
Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P.R. China
| | - Qingyu Meng
- College
of Chemistry, Chemical Engineering, and Materials Science and State
Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P.R. China
| | - Yingjing Yan
- College
of Chemistry, Chemical Engineering, and Materials Science and State
Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P.R. China
| | - Josep M. Poblet
- Departament
de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, Tarragona 43007, Spain
| | - Lei Sun
- Department
of Chemistry, School of Science and Research Center for Industries
of the Future, Westlake University, Hangzhou, Zhejiang Province 310030, China
- Institute
of Natural Sciences, Westlake Institute
for Advanced Study, Hangzhou, Zhejiang Province 310024, China
- Key
Laboratory for Quantum Materials of Zhejiang Province, Department
of Physics, School of Science, Westlake
University, Hangzhou, Zhejiang Province 310030, China
| | - Antonio Rodríguez-Fortea
- Departament
de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, Tarragona 43007, Spain
| | - Ning Chen
- College
of Chemistry, Chemical Engineering, and Materials Science and State
Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu 215123, P.R. China
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18
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Boronski JT, Griffin LP, Conder C, Crumpton AE, Wales LL, Aldridge S. On the nature and limits of alkaline earth-triel bonding. Chem Sci 2024:d4sc03832k. [PMID: 39234213 PMCID: PMC11367318 DOI: 10.1039/d4sc03832k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Accepted: 08/21/2024] [Indexed: 09/06/2024] Open
Abstract
The synthesis of a series of isostructural organometallic complexes featuring Ae-Tr bonds (Ae = Be, Mg; Tr = Al, Ga, In) has been investigated, and their electronic structures probed by quantum chemical calculations. This systematic study allows for comparison, not only of the metal-metal bonding chemistries of the two lightest alkaline earth (Ae) elements, beryllium and magnesium, but also of the three triel (Tr) elements, aluminium, gallium, and indium. Computational analyses (NBO, QTAIM, EDA-NOCV) reveal that Be-Tr bonding is more covalent than Mg-Tr bonding. More strikingly, these calculations predict that the beryllium-indyl complex - featuring the first structurally characterised Be-In bond - should act as a source of nucleophilic beryllium. This has been confirmed experimentally by its reactivity towards methyl iodide, which yields the Be-Me functionality. By extension, the electrophilic character of the beryllium centre in the beryllium-gallyl complex contrasts with the umpoled, nucleophilic behaviour of the beryllium centre in both the -indyl and -aluminyl complexes.
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Affiliation(s)
- Josef T Boronski
- Chemistry Research Laboratory, Department of Chemistry Oxford OX1 3TA UK
| | - Liam P Griffin
- Chemistry Research Laboratory, Department of Chemistry Oxford OX1 3TA UK
| | - Caroline Conder
- Chemistry Research Laboratory, Department of Chemistry Oxford OX1 3TA UK
| | | | - Lewis L Wales
- Chemistry Research Laboratory, Department of Chemistry Oxford OX1 3TA UK
| | - Simon Aldridge
- Chemistry Research Laboratory, Department of Chemistry Oxford OX1 3TA UK
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19
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Berthold C, Maurer J, Klerner L, Harder S, Buchner MR. Formation, Structure and Reactivity of a Beryllium(0) Complex with Mg δ+-Be δ- Bond Polarization. Angew Chem Int Ed Engl 2024; 63:e202408422. [PMID: 38818668 DOI: 10.1002/anie.202408422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Revised: 05/22/2024] [Accepted: 05/27/2024] [Indexed: 06/01/2024]
Abstract
Attempts to create a novel Mg-Be bond by reaction of [(DIPePBDI*)MgNa]2 with Be[N(SiMe3)2]2 failed; DIPePBDI*=HC[(tBu)C=N(DIPeP)]2, DIPeP=2,6-Et2C-phenyl. Even at elevated temperatures, no conversion was observed. This is likely caused by strong steric shielding of the Be center. A similar reaction with the more open Cp*BeCl gave in quantitative yield (DIPePBDI*)MgBeCp* (1). The crystal structure shows a Mg-Be bond of 2.469(4) Å. Homolytic cleavage of the Mg-Be bond requires ΔH=69.6 kcal mol-1 (cf. CpBe-BeCp 69.0 kcal mol-1 and (DIPPBDI)Mg-Mg(DIPPBDI) 55.8 kcal mol-1). Natural-Population-Analysis (NPA) shows fragment charges: (DIPePBDI*)Mg +0.27/BeCp* -0.27. The very low NPA charge on Be (+0.62) compared to Mg (+1.21) and the strongly upfield 9Be NMR signal at -23.7 ppm are in line with considerable electron density on Be and the formal oxidation state assignment of MgII-Be0. Despite this Mgδ+-Beδ- polarity, 1 is extremely thermally stable and unreactive towards H2, CO, N2, cyclohexene and carbodiimide. It reacted with benzophenone, azobenzene, phenyl acetylene, CO2 and CS2. Reaction with 1-adamantyl azide led to reductive coupling and formation of an N6-chain. The azide reagent also inserted in the Cp*-Be bond. The inertness of 1 is likely due to bulky ligands protecting the Mg-Be unit.
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Affiliation(s)
| | - Johannes Maurer
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Lukas Klerner
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Sjoerd Harder
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Magnus R Buchner
- Fachbereich Chemie, Philipps-Universität Marburg, 35043, Marburg, Germany
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20
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Wang LS. Borozenes: Benzene-Like Planar Aromatic Boron Clusters. Acc Chem Res 2024; 57:2428-2436. [PMID: 39096510 DOI: 10.1021/acs.accounts.4c00380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/05/2024]
Abstract
ConspectusWith three valence electrons and four valence orbitals, boron (2s22p1) is an electron-deficient element, resulting in interesting chemical bonding and structures in both borane molecules and bulk boron materials. The electron deficiency leads to electron sharing and delocalization in borane compounds and bulk boron allotropes, characterized by polyhedral cages, in particular, the ubiquitous B12 icosahedral cage. During the past two decades, the structures and bonding of size-selected boron clusters have been elucidated via combined photoelectron spectroscopy and theoretical investigations. Unlike bulk boron materials, finite boron clusters have been found to possess 2D structures consisting of B3 triangles, dotted with tetragonal, pentagonal, or hexagonal holes. The discovery of the planar B36 cluster with a central hexagonal hole provided the first experimental evidence for the viability of 2D boron nanostructures (borophene), which have been synthesized on inert substrates. The B7-, B8-, and B9- clusters were among the first few boron clusters to be investigated by joint photoelectron spectroscopy and theoretical calculations, and they were all found to possess 2D structures with a central B atom inside a Bn ring. Recently, the B73- (C6v), B82- (D7h), and B9- (D8h) series of closed-shell species were shown to possess similar π bonding akin to that in the C5H5-, C6H6, and C7H7+ series, respectively, and the name "borozene" was coined to highlight their analogy to the classical aromatic hydrocarbon molecules.Among the borozenes, the D7h B82- species is unique for its high stability originating from both its double aromaticity and the fact that the B7 ring has the perfect size to host a central B atom. The B82- borozene has been realized experimentally in a variety of MB8 and M2B8 complexes. In particular, the B82- borozene has been observed to stabilize the rare valence-I oxidation state of lanthanides in LnB8- complexes, as well as a Cu2+ species in Cu2B8-. The B6 ring in B73- is too small to host a B atom, resulting in a slight out-of-plane distortion. Interestingly, the bowl-shaped B7 borozene is perfect for coordination to a metal atom, leading to the observation of a series of highly stable MB7 borozene complexes. On the other hand, the B8 ring is slightly too large to host the central B atom, such that a low-lying and low-symmetry isomer also exists for B9-. Even though most 2D boron clusters are aromatic, the B73-, B82-, and B9- borozenes are special because of their high symmetries and their analogy to the series of C5H5-, C6H6, and C7H7+ prototypical aromatic compounds. This Account discusses recent experimental and theoretical advances on the investigations of various borozene complexes. It is expected that many new borozene compounds can be designed and may be eventually synthesized.
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Affiliation(s)
- Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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21
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Pearce KG, Neale SE, Mahon MF, McMullin CL, Hill MS. Alkali metal reduction of crown ether encapsulated alkali metal cations. Chem Commun (Camb) 2024; 60:8391-8394. [PMID: 39037395 DOI: 10.1039/d4cc02725f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/23/2024]
Abstract
[{SiNDipp}BeClM]2 ({SiNDipp} = {CH2SiMe2N(Dipp)}2; M = Li, Na, K, Rb) are converted to ionic species by treatment with a crown ether. Whereas the lithium derivative reacts with Na or K to provide [{SiNDipp}BeCl]-[M(12-cr-4)2]+ (M = Na, K), the resultant sodium species is resistant to reduction by potassium. These observations are rationalised by a hybrid experimental/theoretical analysis.
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Affiliation(s)
- Kyle G Pearce
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
| | - Samuel E Neale
- 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.
| | - Michael S Hill
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
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22
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Polarizing the Be-Be bond. Nat Chem 2024; 16:1227-1228. [PMID: 38886616 DOI: 10.1038/s41557-024-01548-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
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23
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Nguyen DT, Helling C, Jones C. Synthesis and Characterization of Bulky 1,3-Diamidopropane Complexes of Group 2 Metals (Be-Sr). Chem Asian J 2024; 19:e202400498. [PMID: 38760323 DOI: 10.1002/asia.202400498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 05/14/2024] [Accepted: 05/17/2024] [Indexed: 05/19/2024]
Abstract
Reaction of lithium 1,3-diamidopropane Li2(TripNCN) (TripNCN=[{(Trip)NCH2}2CH2]2-, Trip=2,4,6-triisopropylphenyl) with BeBr2(OEt2)2 gave the diamido beryllium complex, [(TripNCN)Be(OEt2)]. Deprotonation reactions between the bulkier 1,3-diaminopropane (TCHPNCN)H2 (TCHPNCN=[{(TCHP)NCH2}2CH2]2-, TCHP=2,4,6-tricyclohexylphenyl) and magnesium alkyls afforded the adduct complexes [(TCHPNCN)Mg(OEt2)] and [(TCHPNCN)Mg(THF)2], depending on the reaction conditions employed. Treating [(TCHPNCN)Mg(THF)2] with the N-heterocyclic carbene :C{(MeNCMe)2} (TMC) gave [(TCHPNCN)Mg(TMC)2] via substitution of the THF ligands. Reactions of (ArNCN)H2 (Ar=Trip or TCHP) with Mg{CH2(SiMe3)}2, in the absence of Lewis bases, yielded the N-bridged dimers [{(ArNCN)Mg}2]. Salt metathesis reactions between alkali metal salts M2(TCHPNCN) (M=Li or K) and CaI2 or SrI2 led to the THF adduct compounds [(TCHPNCN)Ca(THF)3] and [(TCHPNCN)Sr(THF)4], the differing number of THF ligands in which is a result of the different sizes of the metals involved. The described complexes hold potential as precursors to kinetically protected, low oxidation state group 2 metal species.
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Affiliation(s)
- Dat T Nguyen
- School of Chemistry, Monash University, PO Box 23, Melbourne, VIC, 3800, Australia
| | - Christoph Helling
- School of Chemistry, Monash University, PO Box 23, Melbourne, VIC, 3800, Australia
| | - Cameron Jones
- School of Chemistry, Monash University, PO Box 23, Melbourne, VIC, 3800, Australia
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24
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Boronski JT, Crumpton AE, Roper AF, Aldridge S. A nucleophilic beryllyl complex via metathesis at [Be-Be] 2. Nat Chem 2024; 16:1295-1300. [PMID: 38760434 PMCID: PMC11321998 DOI: 10.1038/s41557-024-01534-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 04/10/2024] [Indexed: 05/19/2024]
Abstract
Owing to its high toxicity, the chemistry of element number four, beryllium, is poorly understood. However, as the lightest elements provide the basis for fundamental models of chemical bonding, there is a need for greater insight into the properties of beryllium. In this context, the chemistry of the homo-elemental Be-Be bond is of fundamental interest. Here the ligand metathesis chemistry of diberyllocene (1; CpBeBeCp)-a stable complex with a Be-Be bond-has been investigated. These studies yield two complexes with Be-Be bonds: Cp*BeBeCp (2) and [K{(HCDippN)2BO}2]BeBeCp (3; Dipp = 2,6-diisopropylphenyl). Quantum chemical calculations indicate that the Be-Be bond in 3 is polarized to such an extent that the complex could be formulated as a mixed-oxidation state Be0/BeII complex. Correspondingly, it is demonstrated that 3 can transfer the 'beryllyl' anion, [BeCp]-, to an organic substrate, by analogy with the reactivity of sp2-sp3 diboranes. Indeed, this work reveals striking similarities between the homo-elemental bonding linkages of beryllium and boron, despite the respective metallic and non-metallic natures of these elements.
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Affiliation(s)
- Josef T Boronski
- Chemistry Research Laboratory Department of Chemistry, University of Oxford, Oxford, UK.
| | - Agamemnon E Crumpton
- Chemistry Research Laboratory Department of Chemistry, University of Oxford, Oxford, UK
| | - Aisling F Roper
- Chemistry Research Laboratory Department of Chemistry, University of Oxford, Oxford, UK
| | - Simon Aldridge
- Chemistry Research Laboratory Department of Chemistry, University of Oxford, Oxford, UK.
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25
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Ruppert H, Meister A, Janßen P, Greb L. Conformational and Substitution Effects on the Donor and Reducing Strength of Tin(II) Porphyrinogens. Chemistry 2024; 30:e202401685. [PMID: 38803093 DOI: 10.1002/chem.202401685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 05/24/2024] [Accepted: 05/27/2024] [Indexed: 05/29/2024]
Abstract
Meso-octaalkylcalix[4]pyrrolates are a class of redox-active porphyrinogen ligands. They have been well established in d- and f-block chemistry for over three decades but have only recently been introduced as ligands for p-block elements. Here, we present a study on the influence of meso-substituents on the redox chemistry of calix[4]pyrrolato stannate(II) dianions [2R]2- (R=Me, Et). Expansion of the normal-mode structural decomposition (NSD) method, well known for porphyrin chemistry, provides insights into the ligand conformation of a calix[4]pyrrolato p-block complex. Combined with the results of spectroscopic donor scaling, electrochemical studies, and quantum mechanical bond analysis tools, subtle but significant substitution and conformational effects on the electronic structure are revealed. Exploiting this knowledge rationalizes the role of this class of tin(II) dianions to act as potent reducing agents, but can also be expanded for other central elements. Photoexcitation boosts this reactivity further, allowing for the reduction of even challenging chlorobenzene.
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Affiliation(s)
- Heiko Ruppert
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 275, 69120, Heidelberg, Germany
| | - Arne Meister
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 275, 69120, Heidelberg, Germany
| | - Paul Janßen
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 275, 69120, Heidelberg, Germany
| | - Lutz Greb
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 275, 69120, Heidelberg, Germany
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26
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Mills DP. A molecular sandwich with a lithium-aluminium filling. Nat Chem 2024; 16:1045-1046. [PMID: 38951615 DOI: 10.1038/s41557-024-01563-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/03/2024]
Affiliation(s)
- David P Mills
- Department of Chemistry, The University of Manchester, Manchester, UK.
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27
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Bischoff IA, Danés S, Thoni P, Morgenstern B, Andrada DM, Müller C, Lambert J, Gießelmann ECJ, Zimmer M, Schäfer A. A lithium-aluminium heterobimetallic dimetallocene. Nat Chem 2024; 16:1093-1100. [PMID: 38744915 PMCID: PMC11637000 DOI: 10.1038/s41557-024-01531-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 04/05/2024] [Indexed: 05/16/2024]
Abstract
Homobimetallic dimetallocenes exhibiting two identical metal atoms sandwiched between two η5 bonded cyclopentadienyl rings is a narrow class of compounds, with representative examples being dizincocene and diberyllocene. Here we report the synthesis and structural characterization of a heterobimetallic dimetallocene, accessible through heterocoupling of lithium and aluminylene fragments with pentaisopropylcyclopentadienyl ligands. The Al-Li bond features a high ionic character and profits from attractive dispersion interactions between the isopropyl groups of the cyclopentadienyl ligands. A key synthetic step is the isolation of a cyclopentadienylaluminylene monomer, which also enables the structural characterization of this species. In addition to their structural authentication by single-crystal X-ray diffraction analysis, both compounds were characterized by multinuclear NMR spectroscopy in solution and in the solid state. Furthermore, reactivity studies of the lithium-aluminium heterobimetallic dimetallocene with an N-heterocyclic carbene and different heteroallenes were performed and show that the Al-Li bond is easily cleaved.
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Affiliation(s)
- Inga-Alexandra Bischoff
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany
| | - Sergi Danés
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany
| | - Philipp Thoni
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany
| | - Bernd Morgenstern
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany
| | - Diego M Andrada
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany
| | - Carsten Müller
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany
| | - Jessica Lambert
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany
| | - Elias C J Gießelmann
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany
| | - Michael Zimmer
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany
| | - André Schäfer
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany.
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28
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Goodwin CAP. What is a Sandwich Complex? Inorg Chem 2024; 63:9363-9365. [PMID: 38306455 DOI: 10.1021/acs.inorgchem.4c00243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2024]
Affiliation(s)
- Conrad A P Goodwin
- Department of Chemistry, The University of Manchester, Manchester M13 9PL, United Kingdom
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29
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Evans MJ, Jones C. Low oxidation state and hydrido group 2 complexes: synthesis and applications in the activation of gaseous substrates. Chem Soc Rev 2024; 53:5054-5082. [PMID: 38595211 DOI: 10.1039/d4cs00097h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Numerous industrial processes utilise gaseous chemical feedstocks to produce useful chemical products. Atmospheric and other small molecule gases, including anthropogenic waste products (e.g. carbon dioxide), can be viewed as sustainable building blocks to access value-added chemical commodities and materials. While transition metal complexes have been well documented in the reduction and transformation of these substrates, molecular complexes of the terrestrially abundant alkaline earth metals have also demonstrated promise with remarkable reactivity reported towards an array of industrially relevant gases over the past two decades. This review covers low oxidation state and hydrido group 2 complexes and their role in the reduction and transformation of a selection of important gaseous substrates towards value-added chemical products.
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Affiliation(s)
- Matthew J Evans
- School of Chemistry, Monash University, PO Box 23, Melbourne, Victoria, 3800, Australia.
| | - Cameron Jones
- School of Chemistry, Monash University, PO Box 23, Melbourne, Victoria, 3800, Australia.
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30
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Liu HY, Neale SE, Hill MS, Mahon MF, McMullin CL, Richards E. [{SiN Dipp}MgNa] 2: A Potent Molecular Reducing Agent. Organometallics 2024; 43:879-888. [PMID: 38665773 PMCID: PMC11041119 DOI: 10.1021/acs.organomet.4c00076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 03/17/2024] [Accepted: 03/25/2024] [Indexed: 04/28/2024]
Abstract
The bimetallic species, [{SiNDipp}MgNa]2 [{SiNDipp} = {CH2SiMe2N(Dipp)}2; (Dipp = 2,6-i-Pr2C6H3)], is shown to be a potent reducing agent, able to effect one- or two-electron reduction of either dioxygen, TEMPO, anthracene, benzophenone, or diphenylacetylene. In most cases, the bimetallic reaction products imply that the dissimilar alkaline metal centers react with a level of cooperativity. EPR analysis of the benzophenone-derived reaction and the concurrent isolation of [{SiNDipp}Mg(OCPh2)2], however, illustrate that treatment with such reducible, but O-basic, species can also result in reactivity in which the metals provide independent reaction products. The notable E-stereochemistry of the diphenylacetylene reduction product prompted a computational investigation of the PhC≡CPh addition. This analysis invokes a series of elementary steps that necessitate ring-opening via Mg+ → Na+ amido group migration of the SiNDipp ligand, providing insight into the previously observed lability of the bidentate dianion and its consequent proclivity toward macrocyclization.
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Affiliation(s)
- Han-Ying Liu
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Samuel E. Neale
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Michael S. Hill
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Mary F. Mahon
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Claire L. McMullin
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Emma Richards
- School
of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, U.K.
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31
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Nguyen DT, Helling C, Evans MJ, Jones C. Enforcing Metal-Arene Interactions in Bulky p-Terphenyl Bis(anilide) Complexes of Group 2 Metals (Be-Ba): Potential Precursors for Low-Oxidation-State Alkaline Earth Metal Systems. Inorg Chem 2024; 63:5718-5726. [PMID: 38471088 DOI: 10.1021/acs.inorgchem.4c00207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
An extremely bulky p-terphenyl bis(aniline), p-C6H4{C6H4[N(H)TCHP]-2}2 (TCHP = 2,4,6-tricyclohexylphenyl) TCHPTerphH2, has been developed. Deprotonation of a less bulky analogue, DipTerphH2 (Dip = 2,6-diisopropylphenyl), with BePh2 affords the bimetallic system, [(BePh)2(μ-DipTerph)] 1. Treating either TCHPTerphH2 or DipTerphH2 with Mg{CH2(SiMe3)}2 gives the monomeric bis(anilide) complexes [Mg(ArTerph)] (Ar = Dip 2, TCHP 3) which display rare examples of η6-arene coordination to the metal center. Treating 2 with THF leads to partial dissociation of the Mg···arene interaction and formation of [Mg(DipTerph)(THF)] 4. Reactions of the bis(aniline)s with the group 2 metal amides [M{N(SiMe3)2}2] afford dimeric, structurally analogous compounds [{M(ArTerph)}2] (Ar = Dip, M = Ca 5, Sr 6, Ba 7; Ar = TCHP, M = Ca 8, Sr 9, Ba 10) which display intermolecular M···arene interactions in the solid state. Computational studies have shown that the intramolecular M···η6-arene interactions in models of the ether-free metal bis(anilide) compounds are largely electrostatic in nature. Reductions of these compounds with alkali metals led to mixtures of unidentified products.
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Affiliation(s)
- Dat T Nguyen
- School of Chemistry, Monash University, P.O. Box 23, Melbourne 3800, Victoria, Australia
| | - Christoph Helling
- School of Chemistry, Monash University, P.O. Box 23, Melbourne 3800, Victoria, Australia
| | - Matthew J Evans
- School of Chemistry, Monash University, P.O. Box 23, Melbourne 3800, Victoria, Australia
| | - Cameron Jones
- School of Chemistry, Monash University, P.O. Box 23, Melbourne 3800, Victoria, Australia
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32
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Kozuch S. When, Where and Why Boron Prefers Boron to Nitrogen. Chemphyschem 2024; 25:e202300875. [PMID: 38146920 DOI: 10.1002/cphc.202300875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/20/2023] [Accepted: 12/26/2023] [Indexed: 12/27/2023]
Abstract
Boron is the archetypal Lewis acid, and therefore it is only natural that it prefers to bind nitrogen, its usual Lewis base counterpart. To challenge this assumption, we present a computationally designed bicyclopentane molecule akin to [1.1.1]propellane, but with pyramidal B and N inner atoms bonded by an "inverted" dative bond. Unexpectedly, the dimer of this system prefers to interact via an atypical boron-boron bond over the supposedly obvious boron-nitrogen bond. A molecular orbital analysis shows that the boron in this peculiar entity acts both as an electron donor and an electron acceptor, making the dimerization an amphoteric-amphoteric interaction process.
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Affiliation(s)
- Sebastian Kozuch
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva, Israel, 84105
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33
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Pearce KG, Hill MS, Mahon MF. Cesium Reduction of a Lithium Diamidochloroberyllate. Organometallics 2024; 43:432-437. [PMID: 38362487 PMCID: PMC10865438 DOI: 10.1021/acs.organomet.3c00519] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/10/2024] [Accepted: 01/12/2024] [Indexed: 02/17/2024]
Abstract
Room temperature reaction of elemental cesium with the dimeric lithium chloroberyllate [{SiNDipp}BeClLi]2 [{SiNDipp} = {CH2SiMe2N(Dipp)}2, where Dipp = 2,6-di-isopropylphenyl, in C6D6 results in activation of the arene solvent. Although, in contrast to earlier observations of lithium and sodium metal reduction, the generation of a mooted cesium phenylberyllate could not be confirmed, this process corroborates a previous hypothesis that such beryllium-centered solvent activation also necessitates the formation of hydridoberyllium species. These observations are further borne out by the study of an analogous reaction performed in toluene, in which case the proposed generation of formally low oxidation state beryllium radical anion intermediates induces activation of a toluene sp3 C-H bond and the isolation of the polymeric cesium benzylberyllate, [Cs({SiNDipp}BeCH2C6H5)]∞.
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Affiliation(s)
- Kyle G. Pearce
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Michael S. Hill
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Mary F. Mahon
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
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34
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Parveen D, Yadav RK, Roy DK. Recent progress in beryllium organometallic chemistry. Chem Commun (Camb) 2024; 60:1663-1673. [PMID: 38260953 DOI: 10.1039/d3cc04844f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Beryllium possesses a unique amalgamation of characteristics, its electronegativity included, that not only make it a vital component in a wide range of technical sectors and consumer industries, but also make it an interesting candidate for forming covalently bonded compounds. However, the extremely toxic nature of beryllium, which can cause chronic beryllium disease, has limited the exploration of its chemistry, making beryllium one of the least studied (non-radioactive) elements. The development of selective chelating ligands, sterically encumbered substituents and, moreover, the boom of N-heterocyclic carbenes in organometallic chemistry and main group chemistry has revived the interest in beryllium chemistry. Therefore, some quite remarkable progress in the coordination and organometallic chemistry of beryllium has been made in the last two decades. For example, low oxidation state beryllium compounds, antiaromatic/aromatic beryllium compounds, where beryllium is involved in π-electron delocalization, and the isolation of beryllium-beryllium bonded species have all been achieved. This article provides an oversight over the recent developments in the organometallic chemistry of beryllium.
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Affiliation(s)
- Darakshan Parveen
- Department of Chemistry, Indian Institute of Technology Indore, Madhya Pradesh, 453552, India.
| | - Rahul Kumar Yadav
- Department of Chemistry, Indian Institute of Technology Indore, Madhya Pradesh, 453552, India.
| | - Dipak Kumar Roy
- Department of Chemistry, Indian Institute of Technology Indore, Madhya Pradesh, 453552, India.
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35
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Czernetzki C, Arrowsmith M, Endres L, Krummenacher I, Braunschweig H. Tricoordinate Beryllium Radicals and Their Reactivity. Inorg Chem 2024; 63:2670-2678. [PMID: 38259240 DOI: 10.1021/acs.inorgchem.3c04014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The one-electron reduction of [(CAAC)Be(Dur)Br] (CAAC = cyclic alkyl(amino)carbene, Dur = 2,3,5,6-tetramethylphenyl = duryl) with lithium sand in diethyl ether yields the first neutral, tricoordinate, and moderately stable beryllium radical, [(CAAC)(Et2O)BeDur]• (2-Et2O), which undergoes a facile second one-electron reduction concomitant with the insertion of the beryllium center into the endocyclic C-NCAAC bond and a cyclopropane-forming C-H bond activation of an adjacent methyl group. In situ generation of 2-Et2O and addition of PMe3 yield the stable analogue, [(CAAC)(Me3P)BeDur]• (2-PMe3), which serves as a platform for PMe3-ligand exchange with stronger donors, generating the radicals [(CAAC)LBeDur]• (2-L, L = isocyanides, pyridines, and N-heterocyclic carbenes). X-ray structural analyses show trigonal-planar beryllium centers and strong π backbonding from the metal to the CAAC ligand. The EPR signals of all six isolated [(CAAC)LBeDur]• radicals display significant, albeit small, hyperfine coupling to the 9Be nucleus. DFT calculations show that the spin density is mostly delocalized over the CAAC π framework and, where present, the isocyanide CN moiety, with only a small proportion (3-6%) on the beryllium center. 2-PMe3 proved thermally unstable at 80 °C, first undergoing radical hydrogen abstraction with the solvent, followed by insertion of beryllium into the endocyclic C-NCAAC bond and PMe3 transfer to the former carbene carbon atom. The reactions with diphenyl disulfide and phenyl azide occur at the beryllium center and yield the corresponding Be(II) phenyl sulfide and amino complexes, respectively, the latter concomitant with radical transfer and hydrogen abstraction by the beryllium-bound nitrogen center.
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Affiliation(s)
- Corinna Czernetzki
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
| | - Merle Arrowsmith
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
| | - Lukas Endres
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
| | - Ivo Krummenacher
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
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Weinhold F, Glendening ED. Natural resonance-theoretic conceptions of extreme electronic delocalization in soft materials. Phys Chem Chem Phys 2024; 26:2815-2822. [PMID: 38196333 DOI: 10.1039/d3cp04790c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
In the broad context of Dalton's atomic hypothesis and subsequent classical vs. quantum understanding of macroscopic materials, we show how Pauling's resonance-type conceptions, as quantified in natural resonance theory (NRT) analysis of modern wavefunctions, can be modified to unify description of interatomic interactions from the Lewis-like limit of localized e-pair covalency in molecules to the extreme delocalized limit of supramolecular "soft matter" aggregation. Such "NRT-centric" integration of NRT bond orders for hard- and soft-matter interactions is illustrated with application to a long-predicted and recently synthesized organometallic sandwich-type complex ("diberyllocene") that exhibits bond orders ranging from the soft limit (bBeC ≈ 0.01) to the typical values (bCC ≈ 1.35) of molecular resonance-covalency in the organic domain, with intermediate value (bBeBe ≈ 0.86) for intermetallic Be⋯Be interaction.
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Affiliation(s)
- Frank Weinhold
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA.
| | - Eric D Glendening
- Department of Chemistry and Physics, Indiana State University, Terre Haute, IN 47809, USA.
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37
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Hadlington TJ. An anionic beryllium hydride dimer with an exceedingly short Be⋯Be distance. Dalton Trans 2024; 53:882-886. [PMID: 38168968 DOI: 10.1039/d3dt03976e] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Heteroleptic hydride complexes of the group 2 metals have seen considerable attention as Earth-abundant synthetic tools, yet anionic derivatives are exceedingly rare. We described the facile synthesis and in-depth characterisation of an anionic beryllium hydride dimer, featuring a dynamic [Be2H3] cluster at its core with a short Be⋯Be distance. Despite this, there is no formal Be-Be bond in this complex, with only hydride bridging interactions leading to this remarkable structural attribute.
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Affiliation(s)
- Terrance J Hadlington
- Fakultät für Chemie, Technische Universität München, Lichtenbergstraße 4, 85747 Garching, Germany.
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38
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Cui LJ, Dong X, Liu YQ, Pan S, Cui ZH. Transition Metal Behavior of Heavier Alkaline Earth Elements in Doped Monocyclic and Tubular Boron Clusters. Inorg Chem 2024; 63:653-660. [PMID: 38146259 DOI: 10.1021/acs.inorgchem.3c03536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
Quantum chemical calculations are carried out to design highly symmetric-doped boron clusters by employing the transition metal behavior of heavier alkaline earth (Ae = Ca, Sr, and Ba) metals. Following an electron counting rule, a set of monocyclic and tubular boron clusters capped by two heavier Ae metals were tested, which leads to the highly symmetric Ae2B8, Ae2B18, and Ae2B30 clusters as true minima on the potential energy surface having a monocyclic ring, two-ring tubular, and three-ring tubular boron motifs, respectively. Then, a thorough global minimum (GM) structural search reveals that a monocyclic B8 ring capped with two Ae atoms is indeed a GM for Ca2B8 and Ba2B8, while for Sr2B8 it is a low-lying isomer. Similarly, the present search also unambiguously shows the most stable isomers of Ae2B18 and Ae2B30 to be highly symmetric two- and three-ring tubular boron motifs, respectively, capped with two Ae atoms on each side of the tube. In these Ae-doped boron clusters, in addition to the electrostatic interactions, a substantial covalent interaction, specifically the bonding occurring between (n - 1)d orbitals of Ae and delocalized orbitals of boron motifs, provides the essential driving force behind their highly symmetrical structures and overall stability.
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Affiliation(s)
- Li-Juan Cui
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130023, China
| | - Xue Dong
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130023, China
| | - Yu-Qian Liu
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130023, China
| | - Sudip Pan
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130023, China
| | - Zhong-Hua Cui
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130023, China
- Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), Jilin University, Changchun 130023, China
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39
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Cong F, Cai L, Cheng J, Pu Z, Wang X. Beryllium Dimer Reactions with Acetonitrile: Formation of Strong Be-Be Bonds. Molecules 2023; 29:177. [PMID: 38202759 PMCID: PMC10779904 DOI: 10.3390/molecules29010177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 12/25/2023] [Accepted: 12/26/2023] [Indexed: 01/12/2024] Open
Abstract
Laser ablated Be atoms have been reacted with acetonitrile molecules in 4 K solid neon matrix. The diberyllium products BeBeNCCH3 and CNBeBeCH3 have been identified by D and 13C isotopic substitutions and quantum chemical calculations. The stabilization of the diberyllium species is rationalized from the formation of the real Be-Be single bonds with bond distances as 2.077 and 2.058 Å and binding energies as -27.1 and -77.2 kcal/mol calculated at CCSD (T)/aug-cc-pVTZ level of theory for BeBeNCCH3 and CNBeBeCH3, respectively. EDA-NOCV analysis described the interaction between Be2 and NC···CH3 fragments as Lewis "acid-base" interactions. In the complexes, the Be2 moiety carries positive charges which transfer from antibonding orbital of Be2 to the bonding fragments significantly strengthen the Be-Be bonds that are corroborated by AIM, LOL and NBO analyses. In addition, mono beryllium products BeNCCH3, CNBeCH3, HBeCH2CN and HBeNCCH2 have also been observed in our experiments.
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Affiliation(s)
- Fei Cong
- Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China; (F.C.); (L.C.); (J.C.)
| | - Liyan Cai
- Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China; (F.C.); (L.C.); (J.C.)
| | - Juanjuan Cheng
- Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China; (F.C.); (L.C.); (J.C.)
| | - Zhen Pu
- China Academy of Engineering and Physics, Mianyang 621900, China
| | - Xuefeng Wang
- Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China; (F.C.); (L.C.); (J.C.)
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Boronski JT. Alkaline earth metals: homometallic bonding. Dalton Trans 2023; 53:33-39. [PMID: 38031468 DOI: 10.1039/d3dt03550f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
The study of alkaline earth metal complexes is undergoing a renaissance. Stable molecular species featuring Mg-Mg bonds were reported in 2007 and their reactivity has since been intensively investigated. Motivated by this work, efforts have also been devoted to the synthesis of complexes featuring Be-Be and Ca-Ca bonds. These collective endeavours have revealed that the chemistry of the group 2 metals is richer and more complex than had previously been appreciated. Here, a discussion of the nature of homometallic alkaline earth bonding is presented, recent synthetic advances are described, and future directions are considered.
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Affiliation(s)
- Josef T Boronski
- Chemistry Research Laboratory, Department of Chemistry, Oxford, OX1 3TA, UK.
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41
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Townrow OPE, Färber C, Zenneck U, Harder S. Metal Vapour Synthesis of an Organometallic Barium(0) Synthon. Angew Chem Int Ed Engl 2023:e202318428. [PMID: 38078903 DOI: 10.1002/anie.202318428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Indexed: 12/23/2023]
Abstract
A hydrocarbon-soluble barium anthracene complex was prepared by means of metal vapour synthesis. Reaction of 9,10-bis(trimethylsilyl)anthracene (Anth'') with barium vapour gave deep purple Ba(Anth'') which after extraction with diethyl ether crystallised as the cyclic octamer [Ba(Anth'')⋅Et2 O]8 . Dissolution in benzene or toluene led to replacement of the Et2 O ligand with a softer arene ligand and isolation of Ba(Anth'')⋅arene. Diffusion ordered spectroscopy (DOSY NMR ) measurements in benzene-d6 indicate solution species with a molecular weight that equals a trimeric constitution. Natural population analysis (NPA) assigned charges of +1.70 and -1.70 to Ba and Anth'', respectively, relating to highly ionic Ba2+ /Anth''2- bonding. Preliminary reactivity studies with air, Ph2 C=NPh, or H2 show that the complex reacts as a Ba0 synthon by release of neutral Anth''. This soluble molecular Ba0 /BaII redox synthon provides new routes for the syntheses of barium complexes under mild conditions.
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Affiliation(s)
- Oliver P E Townrow
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Christian Färber
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Ulrich Zenneck
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Sjoerd Harder
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
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42
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Pearce KG, Liu HY, Neale SE, Goff HM, Mahon MF, McMullin CL, Hill MS. Alkali metal reduction of alkali metal cations. Nat Commun 2023; 14:8147. [PMID: 38065953 PMCID: PMC10709313 DOI: 10.1038/s41467-023-43925-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 11/23/2023] [Indexed: 01/25/2024] Open
Abstract
Counter to synthetic convention and expectation provided by the relevant standard reduction potentials, the chloroberyllate, [{SiNDipp}BeClLi]2 [{SiNDipp} = {CH2SiMe2N(Dipp)}2; Dipp = 2,6-i-Pr2C6H3)], reacts with the group 1 elements (M = Na, K, Rb, Cs) to provide the respective heavier alkali metal analogues, [{SiNDipp}BeClM]2, through selective reduction of the Li+ cation. Whereas only [{SiNDipp}BeClRb]2 is amenable to reduction by potassium to its nearest lighter congener, these species may also be sequentially interconverted by treatment of [{SiNDipp}BeClM]2 by the successively heavier group 1 metal. A theoretical analysis combining density functional theory (DFT) with elemental thermochemistry is used to rationalise these observations, where consideration of the relevant enthalpies of atomisation of each alkali metal in its bulk metallic form proved crucial in accounting for experimental observations.
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Affiliation(s)
- Kyle G Pearce
- 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
| | - Samuel E Neale
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Hattie M Goff
- 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.
| | - Michael S Hill
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
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Echeverría J, Alvarez S. The borderless world of chemical bonding across the van der Waals crust and the valence region. Chem Sci 2023; 14:11647-11688. [PMID: 37920358 PMCID: PMC10619631 DOI: 10.1039/d3sc02238b] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 07/01/2023] [Indexed: 11/04/2023] Open
Abstract
The definition of the van der Waals crust as the spherical section between the atomic radius and the van der Waals radius of an element is discussed and a survey of the application of the penetration index between two interacting atoms in a wide variety of covalent, polar, coordinative or noncovalent bonding situations is presented. It is shown that this newly defined parameter permits the comparison of bonding between pairs of atoms in structural and computational studies independently of the atom sizes.
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Affiliation(s)
- Jorge Echeverría
- Instituto de Síntesis Química y Catalisis Homogénea (ISQCH) and Departmento de Química Inorgánica, Facultad de Ciencias, Universidad de Zaragoza Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Santiago Alvarez
- Department de Química Inorgànica i Orgànica, Secció de Química Inorgànica, e Institut de Química Teòrica i Computacional, Universitat de Barcelona Martí i Franquès 1-11 08028 -Barcelona Spain
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R Judge N, Logallo A, Hevia E. Main group metal-mediated strategies for C-H and C-F bond activation and functionalisation of fluoroarenes. Chem Sci 2023; 14:11617-11628. [PMID: 37920337 PMCID: PMC10619642 DOI: 10.1039/d3sc03548d] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 09/11/2023] [Indexed: 11/04/2023] Open
Abstract
With fluoroaromatic compounds increasingly employed as scaffolds in agrochemicals and active pharmaceutical ingredients, the development of methods which facilitate regioselective functionalisation of their C-H and C-F bonds is a frontier of modern synthesis. Along with classical lithiation and nucleophilic aromatic substitution protocols, the vast majority of research efforts have focused on transition metal-mediated transformations enabled by the redox versatilities of these systems. Breaking new ground in this area, recent advances in main group metal chemistry have delineated unique ways in which s-block, Al, Ga and Zn metal complexes can activate this important type of fluorinated molecule. Underpinned by chemical cooperativity, these advances include either the use of heterobimetallic complexes where the combined effect of two metals within a single ligand set enables regioselective low polarity C-H metalation; or the use of novel low valent main group metal complexes supported by special stabilising ligands to induce C-F bond activations. Merging these two different approaches, this Perspective provides an overview of the emerging concept of main-group metal mediated C-H/C-F functionalisation of fluoroarenes. Showcasing the untapped potential that these systems can offer in these processes; focus is placed on how special chemical cooperation is established and how the trapping of key reaction intermediates can inform mechanistic understanding.
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Affiliation(s)
- Neil R Judge
- Departement für Chemie, Biochemie und Pharmazie, Universität Bern Switzerland
| | - Alessandra Logallo
- Departement für Chemie, Biochemie und Pharmazie, Universität Bern Switzerland
| | - Eva Hevia
- Departement für Chemie, Biochemie und Pharmazie, Universität Bern Switzerland
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Buchner MR, Thomas-Hargreaves LR, Berthold C, Bekiş DF, Ivlev SI. A Preference for Heterolepticity - Schlenk Type Equilibria in Organometallic Beryllium Systems. Chemistry 2023; 29:e202302495. [PMID: 37575053 DOI: 10.1002/chem.202302495] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/09/2023] [Accepted: 08/11/2023] [Indexed: 08/15/2023]
Abstract
The reaction of homoleptic beryllium halide with diphenyl beryllium complexes leads to the clean formation of heteroleptic beryllium Grignard compounds [(L)1-2 BePhX]1-2 (X=Cl, Br, I; L=C-, N-, O-donor ligand). The influence of ligands and solvent on these compounds, their formation and exchange equilibria in solution were investigated, together with the factors determining the complex constitution.
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Affiliation(s)
- Magnus R Buchner
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032, Marburg, Germany
| | | | - Chantsalmaa Berthold
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032, Marburg, Germany
| | - Deniz F Bekiş
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032, Marburg, Germany
| | - Sergei I Ivlev
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032, Marburg, Germany
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Naumkin FY. Main-Group Metal Complexes of Benzene: Predicted Features of Stabilization and Isomerization. Molecules 2023; 28:5985. [PMID: 37630238 PMCID: PMC10458619 DOI: 10.3390/molecules28165985] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 08/04/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023] Open
Abstract
Complexes of metal atoms with organic molecules represent a broad variety of systems with many important applications, e.g., in metal-organic interfaces and organometallic chemistry. One class involves aromatic species like benzene (Bz). Here, such complexes with second-group metals are investigated systematically in terms of structure and shape, stability and isomerization, charge distribution and aromaticity, and polarity and IR spectra. Three groups of isomers are identified, varying from metastable to stable ones, in effect featuring "physisorption" or "chemisorption". In particular, the high polarity of binary complexes and nonadditive stabilization of ternary systems for some isomers are found. Also, the Bz component's shape alteration for different isomers and system sizes and related aromaticity variations are predicted to be considerable. Property evolution for the series of metal components is analyzed.
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Affiliation(s)
- Fedor Y Naumkin
- Faculty of Science, Ontario Tech University (UOIT), Oshawa, ON M4W 3C8, Canada
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Abstract
A stable organometallic compound with a Be-Be bond has been synthesized.
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Affiliation(s)
- Jason L Dutton
- Department of Biochemistry and Chemistry, La Trobe University, Melbourne, VIC, Australia
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