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Alkhaibari IS, Zhang X, Zhao J, Stonelake TM, Knighton RC, Horton PN, Coles SJ, Buurma NJ, Richards E, Pope SJA. Tuning Excited State Character in Iridium(III) Photosensitizers and Its Influence on TTA-UC. Inorg Chem 2024. [PMID: 38738860 DOI: 10.1021/acs.inorgchem.4c01003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2024]
Abstract
A series of mixed ligand, photoluminescent organometallic Ir(III) complexes have been synthesized to incorporate substituted 2-phenyl-1H-naphtho[2,3-d]imidazole cyclometalating ligands. The structures of three example complexes were categorically confirmed using X-ray crystallography each sharing very similar structural traits including evidence of interligand hydrogen bond contacts that account for the shielding effects observed in the 1H NMR spectra. The structural iterations of the cyclometalated ligand provide tuning of the principal electronic transitions that determine the visible absorption and emission properties of the complexes: emission can be tuned in the visible region between 550 and 610 nm and with triplet lifetimes up to 10 μs. The nature of the emitting state varies across the series of complexes, with different admixtures of ligand-centered and metal-to-ligand charge transfer triplet levels evident. Finally, the use of the complexes as photosensitizers in triplet-triplet annihilation energy upconversion (TTA-UC) was investigated in the solution state. The study showed that the complexes possessing the longest triplet lifetimes showed good viability as photosensitizers in TTA-UC. Therefore, the use of an electron-withdrawing group on the 2-phenyl-1H-naphtho[2,3-d]imidazole ligand framework can be used to rationally promote TTA-UC using this class of complex.
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Affiliation(s)
- Ibrahim S Alkhaibari
- School of Chemistry, Main Building, Cardiff University, Cardiff, Cymru/Wales CF10 3AT, U.K
- Department of Chemistry, College of Science, Qassim University, Buraydah 52571, Saudi Arabia
| | - Xue Zhang
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, PR China
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, PR China
| | - Thomas M Stonelake
- School of Chemistry, Main Building, Cardiff University, Cardiff, Cymru/Wales CF10 3AT, U.K
| | - Richard C Knighton
- School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, U.K
| | - Peter N Horton
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton SO17 1BJ, U.K
| | - Simon J Coles
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton SO17 1BJ, U.K
| | - Niklaas J Buurma
- School of Chemistry, Main Building, Cardiff University, Cardiff, Cymru/Wales CF10 3AT, U.K
| | - Emma Richards
- School of Chemistry, Main Building, Cardiff University, Cardiff, Cymru/Wales CF10 3AT, U.K
| | - Simon J A Pope
- School of Chemistry, Main Building, Cardiff University, Cardiff, Cymru/Wales CF10 3AT, U.K
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2
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Payce EN, Knighton RC, Platts JA, Horton PN, Coles SJ, Pope SJA. Luminescent Pt(II) Complexes Using Unsymmetrical Bis(2-pyridylimino)isoindolate Analogues. Inorg Chem 2024; 63:8273-8285. [PMID: 38656154 PMCID: PMC11080048 DOI: 10.1021/acs.inorgchem.4c00558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/09/2024] [Accepted: 04/11/2024] [Indexed: 04/26/2024]
Abstract
A series of ligands based upon a 1,3-diimino-isoindoline framework have been synthesized and investigated as pincer-type (N∧N∧N) chelates for Pt(II). The synthetic route allows different combinations of heterocyclic moieties (including pyridyl, thiazole, and isoquinoline) to yield new unsymmetrical ligands. Pt(L1-6)Cl complexes were obtained and characterized using a range of spectroscopic and analytical techniques: 1H and 13C NMR, IR, UV-vis and luminescence spectroscopies, elemental analyses, high-resolution mass spectrometry, electrochemistry, and one example via X-ray crystallography which showed a distorted square planar environment at Pt(II). Cyclic voltammetry on the complexes showed one irreversible oxidation between +0.75 and +1 V (attributed to Pt2+/3+ couple) and a number of ligand-based reductions; in four complexes, two fully reversible reductions were noted between -1.4 and -1.9 V. Photophysical studies showed that Pt(L1-6)Cl absorbs efficiently in the visible region through a combination of ligand-based bands and metal-to-ligand charge-transfer features at 400-550 nm, with assignments supported by DFT calculations. Excitation at 500 nm led to luminescence (studied in both solutions and solid state) in all cases with different combinations of the heterocyclic donors providing tuning of the emission wavelength around 550-678 nm.
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Affiliation(s)
- Ellie N Payce
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, U.K
| | - Richard C Knighton
- School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, England, U.K
| | - James A Platts
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, U.K
| | - Peter N Horton
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton SO17 1BJ, England, U.K
| | - Simon J Coles
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton SO17 1BJ, England, U.K
| | - Simon J A Pope
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, U.K
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3
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Andrews KG, Horton PN, Coles SJ. Programmable synthesis of organic cages with reduced symmetry. Chem Sci 2024; 15:6536-6543. [PMID: 38699263 PMCID: PMC11062111 DOI: 10.1039/d4sc00889h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 03/31/2024] [Indexed: 05/05/2024] Open
Abstract
Integrating symmetry-reducing methods into self-assembly methodology is desirable to efficiently realise the full potential of molecular cages as hosts and catalysts. Although techniques have been explored for metal organic (coordination) cages, rational strategies to develop low symmetry organic cages remain limited. In this article, we describe rules to program the shape and symmetry of organic cage cavities by designing edge pieces that bias the orientation of the amide linkages. We apply the rules to synthesise cages with well-defined cavities, supported by evidence from crystallography, spectroscopy and modelling. Access to low-symmetry, self-assembled organic cages such as those presented, will widen the current bottleneck preventing study of organic enzyme mimics, and provide synthetic tools for novel functional material design.
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Affiliation(s)
- Keith G Andrews
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford Oxford OX1 3TA UK
- Department of Chemistry, Durham University Lower Mount Joy, South Rd Durham DH1 3LE UK
| | - Peter N Horton
- UK National Crystallography Service, School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton Southampton SO17 1BJ UK
| | - Simon J Coles
- UK National Crystallography Service, School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton Southampton SO17 1BJ UK
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Stokes EC, Shoetan IO, Gillman AM, Horton PN, Coles SJ, Woodbury SE, Fallis IA, Pope SJA. Alkyl chain functionalised Ir(iii) complexes: synthesis, properties and behaviour as emissive dopants in microemulsions. RSC Adv 2024; 14:6987-6997. [PMID: 38414995 PMCID: PMC10897649 DOI: 10.1039/d3ra06764e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 02/16/2024] [Indexed: 02/29/2024] Open
Abstract
Six iridium(iii) complexes of the general form [Ir(C^N)2(N^N)]X (where C^N = cyclometalating ligand; N^N = disubstituted 2,2'-bipyridine), and incorporating alkyl chains of differing lengths (C8, C10, C12), have been synthesised and characterised. The complexes have been characterised using a variety of methods including spectroscopies (NMR, IR, UV-Vis, luminescence) and analytical techniques (high resolution mass spectrometry, cyclic voltammetry, X-ray diffraction). Two dodecyl-functionalised complexes were studied for their behaviour in aqueous solutions. Although the complexes did not possess sufficient solubility to determine their critical micelle concentrations (CMC) in water, they were amenable for use as emissive dopants in a N-methyl C12 substituted imidazolium salt microemulsion carrier system with a CMC = 36.5 mM. The investigation showed that the metal doped microemulsions had increased CMCs of 40.4 and 51.3 mM and luminescent properties characterised by the dopant.
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Affiliation(s)
- Emily C Stokes
- School of Chemistry, Cardiff University Main Building Cardiff CF10 3AT UK
| | - Ibrahim O Shoetan
- School of Chemistry, Cardiff University Main Building Cardiff CF10 3AT UK
| | - Alice M Gillman
- School of Chemistry, Cardiff University Main Building Cardiff CF10 3AT UK
| | - Peter N Horton
- Chemistry, UK National Crystallographic Service, Faculty of Natural and Environmental Sciences, University of Southampton Highfield Southampton SO17 1BJ England UK
| | - Simon J Coles
- Chemistry, UK National Crystallographic Service, Faculty of Natural and Environmental Sciences, University of Southampton Highfield Southampton SO17 1BJ England UK
| | - Simon E Woodbury
- National Nuclear Laboratory, Central Laboratory Sellafield, Seascale Cumbria CA20 1PG UK
| | - Ian A Fallis
- School of Chemistry, Cardiff University Main Building Cardiff CF10 3AT UK
| | - Simon J A Pope
- School of Chemistry, Cardiff University Main Building Cardiff CF10 3AT UK
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Fitzgerald SA, Payce EN, Horton PN, Coles SJ, Pope SJA. 2-(Thienyl)quinoxaline derivatives and their application in Ir(III) complexes yielding tuneable deep red emitters. Dalton Trans 2023; 52:16480-16491. [PMID: 37874197 DOI: 10.1039/d3dt02193a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
The synthesis and characterisation of eleven different 2-(thienyl)quinoxaline species that incorporate different points of functionality, including at the thiophene or quinoxaline rings, are described. These species display variable fluorescence properties in the visible region (λem = 401-491 nm) depending upon the molecular structures and extent of conjugation. The series of 2-(thienyl)quinoxaline species were then investigated as cyclometalating agents for Ir(III) to yield [Ir(C^N)2(bipy)]PF6 (where C^N = the cyclometalated ligand; bipy = 2,2'-bipyridine). Eight complexes were successfully isolated and fully characterised by an array of spectroscopic and analytical techniques. Two Ir(III) examples were structurally characterised in the solid state using single crystal X-ray diffraction; both structures confirmed the proposed formulations and coordination spheres in each case showing that the thiophene coordinates via a Ir-C bond. The photophysical properties of the complexes revealed that each complex is luminescent under ambient conditions with a range of emission wavelengths observed (665-751 nm) indicating that electronic tuning can be achieved via both the thienyl and quinoxaline moieties.
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Affiliation(s)
- Sophie A Fitzgerald
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, UK.
| | - Ellie N Payce
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, UK.
| | - Peter N Horton
- UK National Crystallographic Service, Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Simon J Coles
- UK National Crystallographic Service, Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Simon J A Pope
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, UK.
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6
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Yao X, Zhang H, Kong F, Hinaut A, Pawlak R, Okuno M, Graf R, Horton PN, Coles SJ, Meyer E, Bogani L, Bonn M, Wang HI, Müllen K, Narita A. N=8 Armchair Graphene Nanoribbons: Solution Synthesis and High Charge Carrier Mobility. Angew Chem Int Ed Engl 2023; 62:e202312610. [PMID: 37750665 DOI: 10.1002/anie.202312610] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 09/23/2023] [Accepted: 09/25/2023] [Indexed: 09/27/2023]
Abstract
Structurally defined graphene nanoribbons (GNRs) have emerged as promising candidates for nanoelectronic devices. Low band gap (<1 eV) GNRs are particularly important when considering the Schottky barrier in device performance. Here, we demonstrate the first solution synthesis of 8-AGNRs through a carefully designed arylated polynaphthalene precursor. The efficiency of the oxidative cyclodehydrogenation of the tailor-made polymer precursor into 8-AGNRs was validated by FT-IR, Raman, and UV/Vis-near-infrared (NIR) absorption spectroscopy, and further supported by the synthesis of naphtho[1,2,3,4-ghi]perylene derivatives (1 and 2) as subunits of 8-AGNR, with a width of 0.86 nm as suggested by the X-ray single crystal analysis. Low-temperature scanning tunneling microscopy (STM) and solid-state NMR analyses provided further structural support for 8-AGNR. The resulting 8-AGNR exhibited a remarkable NIR absorption extending up to ∼2400 nm, corresponding to an optical band gap as low as ∼0.52 eV. Moreover, optical-pump TeraHertz-probe spectroscopy revealed charge-carrier mobility in the dc limit of ∼270 cm2 V-1 s-1 for the 8-AGNR.
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Affiliation(s)
- Xuelin Yao
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
- Department of Materials, University of Oxford, OX1 3PH, Oxford, United Kingdom
| | - Heng Zhang
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
| | - Fanmiao Kong
- Department of Materials, University of Oxford, OX1 3PH, Oxford, United Kingdom
| | - Antoine Hinaut
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056, Basel, Switzerland
| | - Rémy Pawlak
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056, Basel, Switzerland
| | - Masanari Okuno
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, 153-8902, Tokyo, Japan
| | - Robert Graf
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
| | - Peter N Horton
- National Crystallography Service, School of Chemistry, University of Southampton, SO17 1BJ, Southampton, United Kingdom
| | - Simon J Coles
- National Crystallography Service, School of Chemistry, University of Southampton, SO17 1BJ, Southampton, United Kingdom
| | - Ernst Meyer
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056, Basel, Switzerland
| | - Lapo Bogani
- Department of Materials, University of Oxford, OX1 3PH, Oxford, United Kingdom
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
| | - Hai I Wang
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
- Nanophotonics, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 1, 3584 CC, Utrecht, The Netherlands
| | - Klaus Müllen
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
| | - Akimitsu Narita
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
- Organic and Carbon Nanomaterials Unit, Okinawa Institute of Science and Technology Graduate University, 904-0495, Okinawa, Japan
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7
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Beckett MA, Horton PN, Hursthouse MB, Timmis JL. Synthesis and Thermal Studies of Two Phosphonium Tetrahydroxidohexaoxidopentaborate(1-) Salts: Single-Crystal XRD Characterization of [ iPrPPh 3][B 5O 6(OH) 4]·3.5H 2O and [MePPh 3][B 5O 6(OH) 4]·B(OH) 3·0.5H 2O. Molecules 2023; 28:6867. [PMID: 37836710 PMCID: PMC10574587 DOI: 10.3390/molecules28196867] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 09/19/2023] [Accepted: 09/27/2023] [Indexed: 10/15/2023] Open
Abstract
Two substituted phosphonium tetrahydoxidohexaoxidopentaborate(1-) salts, [iPrPPh3][B5O6(OH)4]·3.5H2O (1) and [MePPh3][B5O6(OH)4]·B(OH)3·0.5H2O (2), were prepared by templated self-assembly processes with good yields by crystallization from basic methanolic aqueous solutions primed with B(OH)3 and the appropriate phosphonium cation. Salts 1 and 2 were characterized by spectroscopic (NMR and IR) and thermal (TGA/DSC) analysis. Salts 1 and 2 were thermally decomposed in air at 800 °C to glassy solids via the anhydrous phosphonium polyborates that are formed at lower temperatures (<300 °C). BET analysis of the anhydrous and pyrolysed materials indicated they were non-porous with surface areas of 0.2-2.75 m2/g. Rhe recrystallization of 1 and 2 from aqueous solution afforded crystals suitable for single-crystal XRD analyses. The structure of 1 comprises alternating cationic/anionic layers with the H2O/pentaborate(1-) planes held together by H-bonds. The cationic planes have offset face-to-face (off) and vertex-to-face (vf) aromatic ring interactions with the iPr groups oriented towards the pentaborate(1-)/H2O layers. The anionic lattice in 2 is expanded by the inclusion of B(OH)3 molecules to accommodate the large cations; this results in the formation of a stacked pentaborate(1-)/B(OH)3 structure with channels occupied by the cations. The cations within the channels have vf, ef (edge-to-face), and off phenyl embraces. Both H-bonding and phenyl embrace interactions are important in stabilizing these two solid-state structures.
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Affiliation(s)
| | - Peter N. Horton
- Chemistry Department, University of Southampton, Southampton SO17 1BJ, UK
| | | | - James L. Timmis
- School of Natural Sciences, Bangor University, Bangor LL57 2UW, UK
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Lin Q, Lan H, Ma C, Stendall RT, Shankland K, Musgrave RA, Horton PN, Baldauf C, Hofmann H, Butts CP, Müller MM, Cobb AJA. Crystal Structure and NMR of an α,δ-Peptide Foldamer Helix Shows Side-Chains are Well Placed for Bifunctional Catalysis: Application as a Minimalist Aldolase Mimic. Angew Chem Weinheim Bergstr Ger 2023; 135:e202305326. [PMID: 38516402 PMCID: PMC10952562 DOI: 10.1002/ange.202305326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Indexed: 03/23/2024]
Abstract
We report the first NMR and X-ray diffraction (XRD) structures of an unusual 13/11-helix (alternating i, i+1 {NH-O=C} and i, i+3 {C=O-H-N} H-bonds) formed by a heteromeric 1 : 1 sequence of α- and δ-amino acids, and demonstrate the application of this framework towards catalysis. Whilst intramolecular hydrogen bonds (IMHBs) are the clear driver of helix formation in this system, we also observe an apolar interaction between the ethyl residue of one δ-amino acid and the cyclohexyl group of the next δ-residue in the sequence that seems to stabilize one type of helix over another. To the best of our knowledge this type of additional stabilization leading to a specific helical preference has not been observed before. Critically, the helix type realized places the α-residue functionalities in positions proximal enough to engage in bifunctional catalysis as demonstrated in the application of our system as a minimalist aldolase mimic.
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Affiliation(s)
- Qi Lin
- Department of ChemistryKing's College London7 Trinity StreetLondonSE1 1DBUK
| | - Hao Lan
- School of ChemistryUniversity of BristolCantocks CloseBristolBS8 1TSUK
| | - Chunmiao Ma
- School of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074P. R. China
| | - Ryan T. Stendall
- Department of ChemistryKing's College London7 Trinity StreetLondonSE1 1DBUK
| | - Kenneth Shankland
- School of ChemistryFood and Pharmacy (SCFP)University of ReadingWhiteknights BerksReadingRG6 6ADUK
| | | | - Peter N. Horton
- EPSRC National Crystallography ServiceSchool of ChemistryUniversity of Southampton HighfieldSouthamptonSO17 1BJUK
| | - Carsten Baldauf
- Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4–614195BerlinGermany
| | - Hans‐Jörg Hofmann
- Institut für BiochemieUniversität LeipzigBrüderstrasse 3404103LeipzigGermany
| | - Craig P. Butts
- School of ChemistryUniversity of BristolCantocks CloseBristolBS8 1TSUK
| | - Manuel M. Müller
- Department of ChemistryKing's College London7 Trinity StreetLondonSE1 1DBUK
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9
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Lin Q, Lan H, Ma C, Stendall RT, Shankland K, Musgrave RA, Horton PN, Baldauf C, Hofmann H, Butts CP, Müller MM, Cobb AJA. Crystal Structure and NMR of an α,δ-Peptide Foldamer Helix Shows Side-Chains are Well Placed for Bifunctional Catalysis: Application as a Minimalist Aldolase Mimic. Angew Chem Int Ed Engl 2023; 62:e202305326. [PMID: 37218617 PMCID: PMC10952276 DOI: 10.1002/anie.202305326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 05/17/2023] [Accepted: 05/22/2023] [Indexed: 05/24/2023]
Abstract
We report the first NMR and X-ray diffraction (XRD) structures of an unusual 13/11-helix (alternating i, i+1 {NH-O=C} and i, i+3 {C=O-H-N} H-bonds) formed by a heteromeric 1 : 1 sequence of α- and δ-amino acids, and demonstrate the application of this framework towards catalysis. Whilst intramolecular hydrogen bonds (IMHBs) are the clear driver of helix formation in this system, we also observe an apolar interaction between the ethyl residue of one δ-amino acid and the cyclohexyl group of the next δ-residue in the sequence that seems to stabilize one type of helix over another. To the best of our knowledge this type of additional stabilization leading to a specific helical preference has not been observed before. Critically, the helix type realized places the α-residue functionalities in positions proximal enough to engage in bifunctional catalysis as demonstrated in the application of our system as a minimalist aldolase mimic.
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Affiliation(s)
- Qi Lin
- Department of ChemistryKing's College London7 Trinity StreetLondonSE1 1DBUK
| | - Hao Lan
- School of ChemistryUniversity of BristolCantocks CloseBristolBS8 1TSUK
| | - Chunmiao Ma
- School of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074P. R. China
| | - Ryan T. Stendall
- Department of ChemistryKing's College London7 Trinity StreetLondonSE1 1DBUK
| | - Kenneth Shankland
- School of ChemistryFood and Pharmacy (SCFP)University of ReadingWhiteknights BerksReadingRG6 6ADUK
| | | | - Peter N. Horton
- EPSRC National Crystallography ServiceSchool of ChemistryUniversity of Southampton HighfieldSouthamptonSO17 1BJUK
| | - Carsten Baldauf
- Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4–614195BerlinGermany
| | - Hans‐Jörg Hofmann
- Institut für BiochemieUniversität LeipzigBrüderstrasse 3404103LeipzigGermany
| | - Craig P. Butts
- School of ChemistryUniversity of BristolCantocks CloseBristolBS8 1TSUK
| | - Manuel M. Müller
- Department of ChemistryKing's College London7 Trinity StreetLondonSE1 1DBUK
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10
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Chen Q, Thompson AL, Christensen KE, Horton PN, Coles SJ, Anderson HL. β,β-Directly Linked Porphyrin Rings: Synthesis, Photophysical Properties, and Fullerene Binding. J Am Chem Soc 2023; 145:11859-11865. [PMID: 37201942 DOI: 10.1021/jacs.3c03549] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Cyclic porphyrin oligomers have been studied as models for photosynthetic light-harvesting antenna complexes and as potential receptors for supramolecular chemistry. Here, we report the synthesis of unprecedented β,β-directly linked cyclic zinc porphyrin oligomers, the trimer (CP3) and tetramer (CP4), by Yamamoto coupling of a 2,3-dibromoporphyrin precursor. Their three-dimensional structures were confirmed by nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, and single-crystal X-ray diffraction analyses. The minimum-energy geometries of CP3 and CP4 have propeller and saddle shapes, respectively, as calculated using density functional theory. Their different geometries result in distinct photophysical and electrochemical properties. The smaller dihedral angles between the porphyrin units in CP3, compared with CP4, result in stronger π-conjugation, splitting the ultraviolet-vis absorption bands and shifting them to longer wavelengths. Analysis of the crystallographic bond lengths indicates that the central benzene ring of the CP3 is partially aromatic [harmonic oscillator model of aromaticity (HOMA) 0.52], whereas the central cyclooctatetraene ring of the CP4 is non-aromatic (HOMA -0.02). The saddle-shaped structure of CP4 makes it a ditopic receptor for fullerenes, with affinity constants of (1.1 ± 0.4) × 105 M-1 for C70 and (2.2 ± 0.1) × 104 M-1 for C60, respectively, in toluene solution at 298 K. The formation of a 1:2 complex with C60 is confirmed by NMR titration and single-crystal X-ray diffraction.
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Affiliation(s)
- Qiang Chen
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, U.K
| | - Amber L Thompson
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, U.K
| | - Kirsten E Christensen
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, U.K
| | - Peter N Horton
- National Crystallography Service, School of Chemistry, University of Southampton, Southampton SO17 1BJ, U.K
| | - Simon J Coles
- National Crystallography Service, School of Chemistry, University of Southampton, Southampton SO17 1BJ, U.K
| | - Harry L Anderson
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, U.K
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11
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Beckett MA, Coles SJ, Horton PN, Rixon TA. Structural (XRD) Characterization and an Analysis of H-Bonding Motifs in Some Tetrahydroxidohexaoxidopentaborate(1-) Salts of N-Substituted Guanidinium Cations. Molecules 2023; 28:molecules28073273. [PMID: 37050036 PMCID: PMC10096507 DOI: 10.3390/molecules28073273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/04/2023] [Accepted: 04/05/2023] [Indexed: 04/14/2023] Open
Abstract
The synthesis and characterization of six new substituted guanidium tetrahydroxidohexaoxidopentaborate(1-) salts are reported: [C(NH2)2(NHMe)][B5O6(OH)4]·H2O (1), [C(NH2)2(NH{NH2})][B5O6(OH)4] (2), [C(NH2)2(NMe2)][B5O6(OH)4] (3), [C(NH2)(NMe2)2][B5O6(OH)4] (4), [C(NHMe)(NMe2)2][B5O6(OH)4]·B(OH)3 (5), and [TBDH][B5O6(OH)4] (6) (TBD = 1,5,7-triazabicyclo [4.4.0]dec-5-ene). Compounds 1-6 were prepared as crystalline salts from basic aqueous solution via self-assembly processes from B(OH)3 and the appropriate substituted cation. Compounds 1-6 were characterized by spectroscopic (NMR and IR) and by single-crystal XRD studies. A thermal (TGA) analysis on compounds 1-3 and 6 demonstrated that they thermally decomposed via a multistage process to B2O3 at >650 °C. The low temperature stage (<250 °C) was endothermic and corresponded to a loss of H2O. Reactant stoichiometry, solid-state packing, and H-bonding interactions are all important in assembling these structures. An analysis of H-bonding motifs in known unsubstituted guanidinium salts [C(NH2)3]2[B4O5(OH)4]·2H2O, [C(NH2)3][B5O6(OH)4]·H2O, and [C(NH2)3]3[B9O12(OH)6] and in compounds 1-6 revealed that two important H-bonding R22(8) motifs competed to stabilize the observed structures. The guanidinium cation formed charge-assisted pincer cation-anion H-bonded rings as a major motif in [C(NH2)3]2[B4O5(OH)4]·2H2O and [C(NH2)3]3[B9O12(OH)6], whereas the anion-anion ring motif was dominant in [C(NH2)3][B5O6(OH)4]·H2O and in compounds 1-6. This behaviour was consistent with the stoichiometry of the salt and packing effects also strongly influencing their solid-state structures.
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Affiliation(s)
- Michael A Beckett
- School of Natural Sciences, Bangor University, Bangor, Gwynedd LL57 2UW, UK
| | - Simon J Coles
- Chemistry Department, University of Southampton, Southampton SO17 1BJ, UK
| | - Peter N Horton
- Chemistry Department, University of Southampton, Southampton SO17 1BJ, UK
| | - Thomas A Rixon
- School of Natural Sciences, Bangor University, Bangor, Gwynedd LL57 2UW, UK
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12
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Parkin S, Glidewell C, Horton PN. (E,E)-1,1'-[1,2-Bis(4-chlorophenyl)ethane-1,2-diyl]bis(phenyldiazene) revisited: threefold configurational disorder of (S,S), (R,R) and (S,R) isomers, a detailed critique. Acta Crystallogr C Struct Chem 2023; 79:77-82. [PMID: 36871289 DOI: 10.1107/s2053229623001262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 02/10/2023] [Indexed: 02/17/2023] Open
Abstract
Crystal structures described as concomitant triclinic (I) and monoclinic (II) polymorphs of meso-(E,E)-1,1'-[1,2-bis(4-chlorophenyl)ethane-1,2-diyl]bis(phenyldiazene) [Mohamed et al. (2016). Acta Cryst. C72, 57-62] have been re-investigated. The published model for II was distorted due to forcing the symmetry of space group C2/c on an incomplete structure model. It is shown here to be a likely three-component superposition of S,S and R,R enantiomers with a lesser amount of the meso form. A detailed analysis of how the improbable distortion in the published model aroused suspicion and the subsequent construction of undistorted chemically and crystallographically plausible alternatives having the symmetry of Cc and C2/c is presented. For the sake of completeness, an improved model for the triclinic P-1 structure of the meso isomer I, revised to include a minor disorder component, is also given.
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Affiliation(s)
- Sean Parkin
- Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055, USA
| | | | - Peter N Horton
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, United Kingdom
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13
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Fitzgerald SA, Xiao X, Zhao J, Horton PN, Coles SJ, Knighton RC, Ward BD, Pope SJA. Organometallic Platinum(II) Photosensitisers that Demonstrate Ligand-Modulated Triplet-Triplet Annihilation Energy Upconversion Efficiencies. Chemistry 2023; 29:e202203241. [PMID: 36394514 PMCID: PMC10107691 DOI: 10.1002/chem.202203241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 11/18/2022]
Abstract
A series of 2-phenylquinoxaline ligands have been synthesised that introduce either CF3 or OCF3 electron-withdrawing groups at different positions of the phenyl ring. These ligands were investigated as cyclometalating reagents for platinum(II) to give neutral complexes of the form [Pt(C^N)(acac)] (in which C^N=cyclometalating ligand; acac=acetyl acetonate). X-ray crystallographic studies on three examples showed that the complexes adopt an approximate square planar geometry. All examples revealed strong Pt-Pt linear contacts of 3.2041(6), 3.2199(3) and 3.2586(2) Å. The highly coloured complexes display efficient visible absorption at 400-500 nm (ϵ ≈5000 M-1 cm-1 ) and orange red photoluminescent characteristics (λem =603-620 nm; Φem ≤37 %), which were subtly tuned by the ligand. Triplet emitting character was confirmed by microsecond luminescence lifetimes and the photogeneration of singlet oxygen with quantum efficiencies up to 57 %. Each complex was investigated as a photosensitiser for triplet-triplet annihilation energy upconversion using 9,10-diphenylanthracene as the annihilator species: a range of good upconversion efficiencies (ΦUC 5.9-14.1 %) were observed and shown to be strongly influenced by the ligand structure in each case.
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Affiliation(s)
- Sophie A Fitzgerald
- School of Chemistry, Main Building, Cardiff University, Cardiff, CF10 3AT, UK
| | - Xiao Xiao
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, P.R. China
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, P.R. China
| | - Peter N Horton
- UK National Crystallographic Service, Chemistry, University of Southampton Highfield, Southampton, SO17 1BJ, UK
| | - Simon J Coles
- UK National Crystallographic Service, Chemistry, University of Southampton Highfield, Southampton, SO17 1BJ, UK
| | - Richard C Knighton
- School of Chemistry, Main Building, Cardiff University, Cardiff, CF10 3AT, UK
| | - Benjamin D Ward
- School of Chemistry, Main Building, Cardiff University, Cardiff, CF10 3AT, UK
| | - Simon J A Pope
- School of Chemistry, Main Building, Cardiff University, Cardiff, CF10 3AT, UK
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14
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Stawski W, Van Raden JM, Patrick CW, Horton PN, Coles SJ, Anderson HL. Strained Porphyrin Tape-Cycloparaphenylene Hybrid Nanorings. Org Lett 2023; 25:378-383. [PMID: 36626241 PMCID: PMC9872170 DOI: 10.1021/acs.orglett.2c04089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
V-Shaped porphyrin dimers, with masked p-phenylene bridges, undergo efficient oxidative coupling to form meso-meso linked cyclic porphyrin oligomers. Reductive aromatization unmasks the p-phenylenes, increasing the strain. Oxidation then fuses the porphyrin dimers, providing a nanoring with curved walls. The strain in this macrocycle bends the p-phenylene and fused porphyrin dimer units (radii of curvature of 11.4 and 19.0 Å, respectively), but it does not significantly alter the electronic structure of the fused porphyrins.
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Affiliation(s)
- Wojciech Stawski
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, U.K.
| | - Jeff M. Van Raden
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, U.K.
| | - Connor W. Patrick
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, U.K.
| | - Peter N. Horton
- UK
National Crystallographic Service, Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, U.K.
| | - Simon J. Coles
- UK
National Crystallographic Service, Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, U.K.
| | - Harry L. Anderson
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, U.K.,
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15
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Altahan MA, Beckett MA, Coles SJ, Horton PN, Jones CL. Synthesis and characterization of a tertiary amine:boric acid (1:1) co-crystal and a neutral zwitterionic diamine pentaboron adduct. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2022.120998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Al-Riyahee A, Horton PN, Coles SJ, Amoroso AJ, J. A. Pope S. Ni(II), Cu(II) and Zn(II) complexes of functionalised thiosemicarbazone ligands: syntheses and reactivity, characterization and structural studies. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.116079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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17
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Sawicka N, Craze CJ, Horton PN, Coles SJ, Richards E, Pope SJA. Long-lived, near-IR emission from Cr(III) under ambient conditions. Chem Commun (Camb) 2022; 58:5733-5736. [PMID: 35438119 DOI: 10.1039/d2cc01434c] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Bis-terdentate (N^N^N) ligands coordinated to Cr(III) yield complexes that display near-IR emission under aerated solvent conditions at room temperature.
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Affiliation(s)
- Natalia Sawicka
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, UK.
| | - Chloe J Craze
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, UK.
| | - Peter N Horton
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton, SO17 1BJ, England, UK
| | - Simon J Coles
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton, SO17 1BJ, England, UK
| | - Emma Richards
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, UK.
| | - Simon J A Pope
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, UK.
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18
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Coles SJ, Horton PN, Kimber P, Klooster WT, Liu P, Plasser F, Smith MB, Tizzard GJ. Reversible P-P bond cleavage at an iridium(III) metal centre. Chem Commun (Camb) 2022; 58:5598-5601. [PMID: 35437547 DOI: 10.1039/d2cc00706a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Treatment of a κ1-P-monodentate bicyclic diphosphane iridium(III) complex with a labile gold(I) precursor afforded an unusual IrIII/AuI complex in which the P-P single bond has been cleaved. This reaction was cleanly reversed upon addition of tertiary phosphine. Carbon-carbon bond activation, across neighbouring P2C2N rings of the coordinated bicyclic diphosphane, occurred upon thermolysis of the IrIII/AuI complex.
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Affiliation(s)
- Simon J Coles
- UK National Crystallography Service, School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK
| | - Peter N Horton
- UK National Crystallography Service, School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK
| | - Patrick Kimber
- Department of Chemistry, Loughborough University, Loughborough, Leics, LE11 3TU, UK.
| | - Wim T Klooster
- UK National Crystallography Service, School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK
| | - Pingchuan Liu
- Department of Chemistry, Loughborough University, Loughborough, Leics, LE11 3TU, UK.
| | - Felix Plasser
- Department of Chemistry, Loughborough University, Loughborough, Leics, LE11 3TU, UK.
| | - Martin B Smith
- Department of Chemistry, Loughborough University, Loughborough, Leics, LE11 3TU, UK.
| | - Graham J Tizzard
- UK National Crystallography Service, School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK
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19
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Butler IR, Evans DM, Horton PN, Coles SJ, Parker SF, Capelli SC. The spontaneous self-assembly of a molecular water pipe in 3D space. IUCrJ 2022; 9:364-369. [PMID: 35546800 PMCID: PMC9067119 DOI: 10.1107/s2052252522003396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 03/25/2022] [Indexed: 06/15/2023]
Abstract
The self-assembly and self-organization of water molecules are relevant in many fields of research. When water spontaneously reacts with 2,2,6,6-tetra-methyl-piperidine (TMP) to form colourless and crystalline discrete needles, only in the exact ratio of 2:1, it is important to understand the phenomenon. Single-crystal X-ray and neutron diffraction data have unveiled that TMP self-assembles around columns of water molecules, and as such, the resulting adduct may be described as a series of molecular water pipes.
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Affiliation(s)
- Ian R. Butler
- Department of Chemistry, Bangor University, Bangor, Gwynedd LL57 2UW, United Kingdom
| | - Daniel M. Evans
- Department of Chemistry, Bangor University, Bangor, Gwynedd LL57 2UW, United Kingdom
| | - Peter N. Horton
- EPSRC National Crystallography Service, School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Simon J. Coles
- EPSRC National Crystallography Service, School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Stewart F. Parker
- ISIS Neutron and Muon Source, STFC Rutherford Appleton Laboratory, Harwell Science Campus, Didcot OX11 0QX, United Kingdom
| | - Silvia C. Capelli
- ISIS Neutron and Muon Source, STFC Rutherford Appleton Laboratory, Harwell Science Campus, Didcot OX11 0QX, United Kingdom
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20
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Al-Riyahee AAA, Horton PN, Coles SJ, Berry C, Horrocks PD, Pope SJA, Amoroso AJ. N, N'-Substituted thioureas and their metal complexes: syntheses, structures and electronic properties. Dalton Trans 2022; 51:3531-3545. [PMID: 35142775 DOI: 10.1039/d1dt04091j] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The synthesis of six N,N'-substituted thiourea ligands (L1a-L3b) was achieved in two steps. A corresponding extensive series of Cu(I), Cu(II), Ni(II) and Zn(II) complexes (1-24) with varying formulations were synthesised from these ligands by the reaction of a 1 : 1 or a 1 : 2 mixture of Cu(II), Ni(II) and Zn(II) perchlorate or chloride salts. Complexes 1-24 have been comprehensively characterised by mass spectrometry, elemental analysis, UV-vis., IR, and 1H and 13C{1H} NMR spectroscopies where applicable. The X-ray crystal structures were obtained for eight examples: [(L1a)2Cu]ClO4 (1), [(L1c)2Zn](ClO4)2 (4), [(L2a)2Cu]ClO4 (6), [(L2c)2Ni](ClO4)2 (7), [(L1b)2Cu](ClO4) (15), [(L1b)CuCl] (16), [(L4)2CuCl2] (19) and [(L3b)CuClO4] (21). These studies reveal that L1c and L2c represent ligands that have undergone cleavage during reaction with the metal salt; L4 represents an intramolecular rearrangement (via a Hugershoff reaction) of L2b; and in most cases Cu(II) is reduced to Cu(I) during the ligand reaction. The X-ray crystal structures also reveal that 1, 4, 6, 15 and 16 are monometallic species in the solid state; that Cu(I) in 1, 6, 15 and 16 and Zn(II) in 4 are arranged in a distorted tetrahedral geometry; that Cu(I) in 21 adopts a trigonal planar geometry; and that in 7 and 19 the Ni(II) and Cu(II) centres, respectively, possess square planar geometry. Preliminary studies on the biological activity (using the Malaria Sybr Green I Fluorescence assay) of the thiourea containing complexes suggests that the d10 complexes, and increased ligand stoichiometries, may afford higher potency.
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Affiliation(s)
- Ali A A Al-Riyahee
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, UK.
| | - Peter N Horton
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Simon J Coles
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Colin Berry
- School of Biosciences, Cardiff University, CF10 3AT, UK
| | - Paul D Horrocks
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
| | - Simon J A Pope
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, UK.
| | - Angelo J Amoroso
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, UK.
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21
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Yan B, Horton PN, Weston SC, Wedge CJ, Russell AE, Grossel MC. Architectural diversity in the solid-state behaviour of crown ether and [2.2.2]-cryptand complexes of K +TCNQ˙ − salts. CrystEngComm 2022. [DOI: 10.1039/d2ce00773h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ionophore complexes of K(TCNQ˙−)(TCNQ0)n adopt a variety of stacking motifs such as wave-like infinite TCNQ columns separated by K+-cryptates (left) and K+-π-dimerised cation complexes separated by infinite slipped TCNQ stacks (right).
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Affiliation(s)
- Bingjia Yan
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Peter N. Horton
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Simon C. Weston
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Christopher J. Wedge
- Department of Chemical Sciences, University of Huddersfield, Huddersfield, HD1 3DH, UK
| | - Andrea E. Russell
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Martin C. Grossel
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
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22
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Blade H, Horton PN, Morrison JA, Orton JB, Sullivan RA, Coles SJ. Tautomerism troubles: proton transfer modifies the stereochemical assignments in diastereoisomeric structures of spiro-cyclic 5-methyl-2 H-imidazol-4-amine dimers. Acta Crystallogr E Crystallogr Commun 2021; 77:1311-1315. [PMID: 34925905 PMCID: PMC8647748 DOI: 10.1107/s205698902100668x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 06/26/2021] [Indexed: 11/17/2022]
Abstract
During the racemization of a novel pharmaceutical spiro-cyclic imidazole-amine compound, namely, 6'-bromo-N-(6'-bromo-4-meth-oxy-4''-methyl-3'H-di-spiro[cyclo-hexane-1,2'-indene-1',2''-imidazol]-5''-yl)-4-meth-oxy-4''-methyl-3'H-di-spiro-[cyclo-hexane-1,2'-indene-1',2''-imidazol]-5''-imine, C36H41Br2N5O2, two impurities were isolated. These impurities were clearly dimers from mass spectroscopic analysis, however single-crystal diffraction characterization was required for the assignment of stereochemistry. The single-crystal diffraction results revealed subtly different structures to those proposed, due to an unexpected proton transfer. The dimers contain four stereocentres, but two of primary inter-est, and are centrosymmetric, so after careful structure refinement and close inspection it was possible to unambiguously assign the stereochemistry of both the homochiral [(S),(S)- and (R),(R)-] and the heterochiral [(S),(R)- and (R),(S)-] compounds.
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Affiliation(s)
- Helen Blade
- AstraZeneca, Oral Product Development, Pharmaceutical Technology & Development, Operations, Macclesfield, United Kingdom
| | - Peter N. Horton
- School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - James A. Morrison
- AstraZeneca, Chemical Development, Pharmaceutical Technology & Development, Operations, Macclesfield, United Kingdom
| | - James B. Orton
- School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Rachel A. Sullivan
- AstraZeneca, Chemical Development, Pharmaceutical Technology & Development, Operations, Macclesfield, United Kingdom
| | - Simon J. Coles
- School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom
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23
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Alexander FM, Fonrouge SF, Borioni JL, Del Pópolo MG, Horton PN, Coles SJ, Hutchings BP, Crawford DE, James SL. Noria and its derivatives as hosts for chemically and thermally robust Type II porous liquids. Chem Sci 2021; 12:14230-14240. [PMID: 34760209 PMCID: PMC8565397 DOI: 10.1039/d1sc03367k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 10/10/2021] [Indexed: 11/21/2022] Open
Abstract
Porous Liquids (PLs) are a new class of material that possess both fluidity and permanent porosity. As such they can act as enhanced, selective solvents and may ultimately find applications which are not possible for porous solids, such as continuous flow separation processes. Type II PLs consist of empty molecular hosts dissolved in size-excluded solvents and to date have mainly been based on hosts that have limited chemical and thermal stability. Here we identify Noria, a rigid cyclic oligomer as a new host for the synthesis of more robust Type II PLs. Although the structure of Noria is well-documented, we find that literature has overlooked the true composition of bulk Noria samples. We find that bulk samples typically consist of Noria (ca. 40%), a Noria isomer, specifically a resorcinarene trimer, “R3” (ca. 30%) and other unidentified oligomers (ca. 30%). Noria has been characterised crystallographically as a diethyl ether solvate and its 1H NMR spectrum fully assigned for the first time. The previously postulated but unreported R3 has also been characterised crystallographically as a dimethyl sulfoxide solvate, which confirms its alternative connectivity to Noria. Noria and R3 have low solubility which precludes their use in Type II PLs, however, the partially ethylated derivative Noria-OEt dissolves in the size-excluded solvent 15-crown-5 to give a new Type II PL. This PL exhibits enhanced uptake of methane (CH4) gas supporting the presence of empty pores in the liquid. Detailed molecular dynamics simulations support the existence of pores in the liquid and show that occupation of the pores by CH4 is favoured. Overall, this work revises the general accepted composition of bulk Noria samples and shows that Noria derivatives are appropriate for the synthesis of more robust Type II PLs. Porous Liquids (PLs) are a new class of material that possess both fluidity and permanent porosity. Here we identify Noria, a rigid cyclic oligomer as a new host for the synthesis of more robust Type II PLs.![]()
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Affiliation(s)
- Francesca M Alexander
- School of Chemistry and Chemical Engineering, Queen's University Belfast David Keir Building, Stranmillis Road Belfast BT7 1NN UK
| | - Sergio F Fonrouge
- ICB-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo Padre Jorge Contreras 1300 Mendoza M5502 JMA Argentina
| | - José L Borioni
- ICB-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo Padre Jorge Contreras 1300 Mendoza M5502 JMA Argentina
| | - Mario G Del Pópolo
- ICB-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo Padre Jorge Contreras 1300 Mendoza M5502 JMA Argentina
| | - Peter N Horton
- EPSRC National Crystallography Service, School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton Southampton SO17 1BJ UK
| | - Simon J Coles
- EPSRC National Crystallography Service, School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton Southampton SO17 1BJ UK
| | - Benjamin P Hutchings
- School of Chemistry and Chemical Engineering, Queen's University Belfast David Keir Building, Stranmillis Road Belfast BT7 1NN UK
| | - Deborah E Crawford
- School of Chemistry and Bioscience, University of Bradford Richmond Road Bradford BD7 1DP UK
| | - Stuart L James
- School of Chemistry and Chemical Engineering, Queen's University Belfast David Keir Building, Stranmillis Road Belfast BT7 1NN UK
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24
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Alexandropoulos DI, Kong F, Lombardi F, Horton PN, Coles SJ, Bogani L. A manganese (II) dimer bearing the reduced derivatives of nitronyl nitroxides. Polyhedron 2021. [DOI: 10.1016/j.poly.2021.115427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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25
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Fitzgerald SA, Otaif HY, Elgar CE, Sawicka N, Horton PN, Coles SJ, Beames JM, Pope SJA. Polysubstituted Ligand Framework for Color Tuning Phosphorescent Iridium(III) Complexes. Inorg Chem 2021; 60:15467-15484. [PMID: 34605234 DOI: 10.1021/acs.inorgchem.1c02121] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of ligands have been synthesized based upon a polysubstituted 2-phenylquinoxaline core structure. These ligands introduce different combinations of fluorine and methyl substituents on both the phenyl and quinoxaline constituent rings. The resultant investigation of these species as cyclometalating agents for Ir(III) gave cationic complexes of the form [Ir(C^N)2(bipy)]PF6 (where C^N = cyclometalating ligand; bipy = 2,2'-bipyridine). X-ray crystallographic studies were conducted on four complexes and each revealed the expected distorted octahedral geometry based upon a cis-C,C and trans-N,N ligand arrangement at Ir(III). Supporting computational studies predict that each of the complexes share the same general descriptions for the frontier orbitals. TD-DFT calculations suggest MLCT contributions to the lowest energy absorption and a likely MLCT/ILCT/LLCT nature to the emitting state. Experimentally, the complexes display tunable luminescence across the yellow-orange-red part of the visible spectrum (λem = 579-655 nm).
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Affiliation(s)
- Sophie A Fitzgerald
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, United Kingdom
| | - Haleema Y Otaif
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, United Kingdom
| | - Christopher E Elgar
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, United Kingdom
| | - Natalia Sawicka
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, United Kingdom
| | - Peter N Horton
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton SO17 1BJ, England, United Kingdom
| | - Simon J Coles
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton SO17 1BJ, England, United Kingdom
| | - Joseph M Beames
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, United Kingdom
| | - Simon J A Pope
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, Cymru/Wales, United Kingdom
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26
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Evans DM, Hughes DD, Murphy PJ, Horton PN, Coles SJ, de Biani FF, Corsini M, Butler IR. Synthetic Route to 1,1′,2,2′-Tetraiodoferrocene That Avoids Isomerization and the Electrochemistry of Some Tetrahaloferrocenes. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00256] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Daniel M. Evans
- School of Natural Sciences, Bangor University, Bangor, Gwynedd, LL57 2UW, U.K
| | - David D. Hughes
- School of Natural Sciences, Bangor University, Bangor, Gwynedd, LL57 2UW, U.K
| | - Patrick J. Murphy
- School of Natural Sciences, Bangor University, Bangor, Gwynedd, LL57 2UW, U.K
| | - Peter N. Horton
- EPSRC National Crystallography Centre, University of Southampton, Southampton SO17 1BJ. U.K
| | - Simon J. Coles
- EPSRC National Crystallography Centre, University of Southampton, Southampton SO17 1BJ. U.K
| | - Fabrizia Fabrizi de Biani
- Dipartimento di Biotecnologie Chimica e Farmacia and C.I.R.C.M.S.B., Università di Siena Via Aldo Moro, 53100 Siena, Italy
| | - Maddalena Corsini
- Dipartimento di Biotecnologie Chimica e Farmacia and C.I.R.C.M.S.B., Università di Siena Via Aldo Moro, 53100 Siena, Italy
| | - Ian R. Butler
- Department of Electronic Engineering and Computer Science, Bangor University, Bangor, Gwynedd LL57 2DG, U.K
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27
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Podda E, Coles SJ, Horton PN, Lickiss PD, Bull OS, Orton JB, Pintus A, Pugh D, Carla Aragoni M, Davies RP. First example of solid-state luminescent borasiloxane-based chiral helices assembled through N-B bonds. Dalton Trans 2021; 50:3782-3785. [PMID: 33634815 DOI: 10.1039/d1dt00114k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction between differently substituted borasiloxanes and 2,5-bis(3-pyridylethynyl)thiophene provided the first example of luminescent borasiloxane-based chiral helices held together by N-B bonds. The starting building blocks and the helices were fully characterized, and the nature of the N-B bond rationalized by means of theoretical calculations.
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Affiliation(s)
- Enrico Podda
- Dipartimento di Scienze Chimiche e Geologiche, Università Degli Studi di Cagliari, Cittadella Universitaria, Monserrato-Cagliari, Italy.
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28
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Butler IR, Evans DM, Horton PN, Coles SJ, Murphy PJ. 1,1′,2,2′-Tetralithioferrocene and 1,1′,2,2′,3,3′-Hexalithioferrocene: Useful Additions to Ferrocene Precursor Compounds. Organometallics 2021. [DOI: 10.1021/acs.organomet.0c00702] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ian R. Butler
- School of Computer Science and Electronic Engineering, Bangor University, Bangor, Gwynedd, U.K. LL57 1UT
| | - Daniel M. Evans
- School of Natural Sciences, Bangor University, Bangor, Gwynedd U.K., LL57 2UW
| | - Peter N. Horton
- National Crystallography Service, School of Chemistry, University of Southampton, Southampton, U.K. SO17 1BJ
| | - Simon J. Coles
- National Crystallography Service, School of Chemistry, University of Southampton, Southampton, U.K. SO17 1BJ
| | - Patrick J. Murphy
- School of Natural Sciences, Bangor University, Bangor, Gwynedd U.K., LL57 2UW
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29
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Elgar CE, Otaif HY, Zhang X, Zhao J, Horton PN, Coles SJ, Beames JM, Pope SJA. Iridium(III) Sensitisers and Energy Upconversion: The Influence of Ligand Structure upon TTA-UC Performance. Chemistry 2021; 27:3427-3439. [PMID: 33242225 DOI: 10.1002/chem.202004146] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/20/2020] [Indexed: 12/21/2022]
Abstract
Six substituted ligands based upon 2-(naphthalen-1-yl)quinoline-4-carboxylate and 2-(naphthalen-2-yl)quinoline-4-carboxylate have been synthesised in two steps from a range of commercially available isatin derivatives. These species are shown to be effective cyclometallating ligands for IrIII , yielding complexes of the form [Ir(C^N)2 (bipy)]PF6 (where C^N=cyclometallating ligand; bipy=2,2'-bipyridine). X-ray crystallographic studies on three examples demonstrate that the complexes adopt a distorted octahedral geometry wherein a cis-C,C and trans-N,N coordination mode is observed. Intraligand torsional distortions are evident in all cases. The IrIII complexes display photoluminescence in the red part of the visible region (668-693 nm), which is modestly tuneable through the ligand structure. The triplet lifetimes of the complexes are clearly influenced by the precise structure of the ligand in each case. Supporting computational (DFT) studies suggest that the differences in observed triplet lifetime are likely due to differing admixtures of ligand-centred versus MLCT character instilled by the facets of the ligand structure. Triplet-triplet annihilation upconversion (TTA-UC) measurements demonstrate that the complexes based upon the 1-naphthyl derived ligands are viable photosensitisers with upconversion quantum efficiencies of 1.6-6.7 %.
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Affiliation(s)
- Christopher E Elgar
- School of Chemistry, Cardiff University, Main Building, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - Haleema Y Otaif
- School of Chemistry, Cardiff University, Main Building, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - Xue Zhang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116024, P. R. China
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116024, P. R. China
| | - Peter N Horton
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Simon J Coles
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Joseph M Beames
- School of Chemistry, Cardiff University, Main Building, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - Simon J A Pope
- School of Chemistry, Cardiff University, Main Building, Cardiff, CF10 3AT, Cymru/Wales, UK
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30
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Otaif HY, Adams SJ, Horton PN, Coles SJ, Beames JM, Pope SJA. Bis-cyclometalated iridium( iii) complexes with terpyridine analogues: syntheses, structures, spectroscopy and computational studies. RSC Adv 2021; 11:39718-39727. [PMID: 35494133 PMCID: PMC9044569 DOI: 10.1039/d1ra07213g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 12/02/2021] [Indexed: 12/28/2022] Open
Abstract
Two ligands based upon a 2,6-disubstituted pyridine bridge introduce bis-quinoxalinyl units in a fashion that yields analogues to the archetypal terdentate ligand, 2,2′:6′,2′′-terpyridine. The ligands were synthesised from the key intermediate 2,6-bis(bromoacetyl)pyridine: a new, high-yielding route is described for this reagent. Two ligand variants (differentiated by H/Me substituents on the quinoxaline ring) were explored as coordinating moieties for iridium(iii) in the development of luminescent complexes. Computational studies (DFT approaches employing B3LYP, B3LYP/LANL2DZ, and M062X/LANL2DZ levels) were used to investigate the geometric and coordination mode preferences of the new ligands and two possibilities arose from theoretical investigations: [Ir(N^N^N)2]3+ and [Ir(N^N^C)2]+, with the former predicted to be more energetically favourable. Upon synthesis and isolation of the Ir(iii) complexes, X-ray crystallographic studies revealed coordination spheres that were cyclometalated, the structures both showing a [Ir(N^N^C)2]PF6 arrangement. Further spectroscopic characterization via NMR confirmed the ligand arrangements in the complexes, and photophysical studies, supported by DFT, showed that a mixture of metal-to-ligand charge transfer (MLCT) and intra-ligand charge transfer (ILCT) character is likely to contribute to the emission features of the complexes, which phosphoresce orange-red (λem = 580–618 nm). The emission wavelength was influenced by the substituents on the quinoxaline ring (H vs. Me), thereby implying further tuneability is possible with future ligand iterations. Bis-terdentate Ir(iii) complexes incorporate two cyclometalated N^N^C bis-quinoxalinyl type ligands derived from the condensation of 2,6-bis(bromoacetyl)pyridine and different o-phenylenediamines.![]()
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Affiliation(s)
- Haleema Y. Otaif
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, UK
| | - Samuel J. Adams
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, UK
| | - Peter N. Horton
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton, SO17 1BJ, England
| | - Simon J. Coles
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, Highfield, Southampton, SO17 1BJ, England
| | - Joseph M. Beames
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, UK
| | - Simon J. A. Pope
- School of Chemistry, Main Building, Cardiff University, Cardiff CF10 3AT, UK
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31
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Abstract
An unusual crossed dimer motif is present in the solid state in the infinite TCNQ˙− columns of the bis-12-crown-4 complexes of Li and NaTCNQ.
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Affiliation(s)
- Bingjia Yan
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Peter N. Horton
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Simon C. Weston
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Andrea E. Russell
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Martin C. Grossel
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
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32
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Butler IR, Beaumont M, Bruce MI, Zaitseva NN, Iggo JA, Robertson C, Horton PN, Coles SJ. Synthesis and Structures of 1,1′,2-Tribromoferrocene, 1,1′,2,2′-Tetrabromoferrocene, 1,1′,2,2′-Tetrabromoruthenocene: Expanding the Range of Precursors for the Metallocene Chemist’s Toolkit. Aust J Chem 2021. [DOI: 10.1071/ch19184] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The synthesis, characterisation, and isolation of 1,1′,2-tribromoferrocene and 1,1′,2,2′-tetrabromoferrocene, which are key synthons in ferrocene chemistry, are described. These compounds are prepared using α-halide assisted lithiation. The crystal structures of 1,1′,2-tribromoferrocene, 1,1′,2,2′-tetrabromoferrocene, 1,1′-dibromoruthenocene, and 1,1′,2,2′-tetrabromoruthenocene have been determined and are reported together with a brief discussion of the intramolecular forces involved in the crystal structures.
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33
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Altahan MA, Beckett MA, Coles SJ, Horton PN. Oxidopolyborate chemistry: The self-assembled, templated, synthesis, and an XRD study of a 1-D coordination polymer, [Cu(en){B 6O 7(OH) 6}] .3H 2O (en = 1,2-diaminoethane). PHOSPHORUS SULFUR 2020. [DOI: 10.1080/10426507.2020.1804204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
| | | | - Simon J. Coles
- Faculty of Engineering and the Environment Chemistry, University of Southampton, Southampton, United Kingdom
| | - Peter N. Horton
- Faculty of Engineering and the Environment Chemistry, University of Southampton, Southampton, United Kingdom
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34
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Stonelake T, Phillips KA, Otaif HY, Edwardson ZC, Horton PN, Coles SJ, Beames JM, Pope SJA. Spectroscopic and Theoretical Investigation of Color Tuning in Deep-Red Luminescent Iridium(III) Complexes. Inorg Chem 2020; 59:2266-2277. [PMID: 32013422 PMCID: PMC7145353 DOI: 10.1021/acs.inorgchem.9b02991] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Indexed: 12/03/2022]
Abstract
A series of heteroleptic, neutral iridium(III) complexes of the form [Ir(L)2(N^O)] (where L = cyclometalated 2,3-disubstituted quinoxaline and N^O = ancillary picolinate or pyrazinoate) are described in terms of their synthesis and spectroscopic properties, with supporting computational analyses providing additional insight into the electronic properties. The 10 [Ir(L)2(N^O)] complexes were characterized using a range of analytical techniques (including 1H, 13C, and 19F NMR and IR spectroscopies and mass spectrometry). One of the examples was structurally characterized using X-ray diffraction. The redox properties were determined using cyclic voltammetry, and the electronic properties were investigated using UV-vis, time-resolved luminescence, and transient absorption spectroscopies. The complexes are phosphorescent in the red region of the visible spectrum (λem = 633-680 nm), with lifetimes typically of hundreds of nanoseconds and quantum yields ca. 5% in aerated chloroform. A combination of spectroscopic and computational analyses suggests that the long-wavelength absorption and emission properties of these complexes are strongly characterized by a combination of spin-forbidden metal-to-ligand charge-transfer and quinoxaline-centered transitions. The emission wavelength in these complexes can thus be controlled in two ways: first, substitution of the cyclometalating quinoxaline ligand can perturb both the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital levels (LUMO, Cl atoms on the ligand induce the largest bathochromic shift), and second, the choice of the ancillary ligand can influence the HOMO energy (pyrazinoate stabilizes the HOMO, inducing hypsochromic shifts).
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Affiliation(s)
- Thomas
M. Stonelake
- School
of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, Wales
| | - Kaitlin A. Phillips
- School
of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, Wales
| | - Haleema Y. Otaif
- School
of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, Wales
| | | | - Peter N. Horton
- U.K.
National Crystallographic Service, Chemistry, Faculty of Natural and
Environmental Sciences, University of Southampton, Highfield, Southampton SO17 1BJ, U.K.
| | - Simon J. Coles
- U.K.
National Crystallographic Service, Chemistry, Faculty of Natural and
Environmental Sciences, University of Southampton, Highfield, Southampton SO17 1BJ, U.K.
| | - Joseph M. Beames
- School
of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, Wales
| | - Simon J. A. Pope
- School
of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, Wales
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35
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Al-Taie ZS, Anetts SR, Christensen J, Coles SJ, Horton PN, Evans DM, Jones LF, de Kleijne FFJ, Ledbetter SM, Mehdar YTH, Murphy PJ, Wilson JA. Proline derived guanidine catalysts forge extensive H-bonded architectures: a solution and solid state study. RSC Adv 2020; 10:22397-22416. [PMID: 35514555 PMCID: PMC9054603 DOI: 10.1039/c9ra07508a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 02/25/2020] [Indexed: 11/21/2022] Open
Abstract
The preparation of a range of amino acid derived guanidine organocatalysts is reported together with their application to the Michael addition of 2-hydroxy-1,4-napthoquinone to β-nitrostyrene, achieving a maximum ee of 56%. Some insight into the mechanism was sought by using X-ray crystallography and a detailed study of the intra- and intermolecular hydrogen bonding is reported. Catalysts assemble! We present the design and synthesis of a large family of amino acid derived guanidine organic moieties as catalysts in the solution state and building blocks towards extended H-bonded architectures upon crystallisation.![]()
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Affiliation(s)
- Zahraa S. Al-Taie
- Department of Chemistry
- College of Science
- Al-Nahrain University
- Baghdad
- Iraq
| | - Simon R. Anetts
- School of Natural Sciences (Chemistry)
- Bangor University
- Bangor
- UK
| | - Jeppe Christensen
- Diamond Light Source
- Didcot
- UK
- EPSRC National Crystallography Service
- School of Chemistry
| | - Simon J. Coles
- EPSRC National Crystallography Service
- School of Chemistry
- University of Southampton
- Southampton
- UK
| | - Peter N. Horton
- EPSRC National Crystallography Service
- School of Chemistry
- University of Southampton
- Southampton
- UK
| | - Daniel M. Evans
- School of Natural Sciences (Chemistry)
- Bangor University
- Bangor
- UK
| | - Leigh F. Jones
- School of Biological, Physical and Forensic Sciences
- University of Wolverhampton
- UK
| | | | | | | | | | - Jack A. Wilson
- School of Natural Sciences (Chemistry)
- Bangor University
- Bangor
- UK
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36
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Wootton TL, Porter JA, Grewal KS, Chirila PG, Forbes S, Coles SJ, Horton PN, Hamilton A, Whiteoak CJ. Merging Cu-catalysed C–H functionalisation and intramolecular annulations: computational and experimental studies on an expedient construction of complex fused heterocycles. Org Chem Front 2020. [DOI: 10.1039/d0qo00283f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A copper-catalysed protocol for the synthesis of fused dihydrobenzofuran-isoquinolone compounds through an intramolecular annulation of readily accessible benzamide substrates is reported, along with a full DFT study into the mechanism.
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Affiliation(s)
- Timothy L. Wootton
- Biomolecular Sciences Research Centre (BMRC) and Department of Biosciences and Chemistry
- Faculty of Health and Wellbeing
- Sheffield Hallam University
- Sheffield
- UK
| | - Jack A. Porter
- Biomolecular Sciences Research Centre (BMRC) and Department of Biosciences and Chemistry
- Faculty of Health and Wellbeing
- Sheffield Hallam University
- Sheffield
- UK
| | - Karmjit S. Grewal
- Biomolecular Sciences Research Centre (BMRC) and Department of Biosciences and Chemistry
- Faculty of Health and Wellbeing
- Sheffield Hallam University
- Sheffield
- UK
| | - Paula G. Chirila
- Biomolecular Sciences Research Centre (BMRC) and Department of Biosciences and Chemistry
- Faculty of Health and Wellbeing
- Sheffield Hallam University
- Sheffield
- UK
| | - Sarah Forbes
- Biomolecular Sciences Research Centre (BMRC) and Department of Biosciences and Chemistry
- Faculty of Health and Wellbeing
- Sheffield Hallam University
- Sheffield
- UK
| | - Simon J. Coles
- UK National Crystallographic Service
- Chemistry
- Faculty of Natural and Environmental Sciences
- University of Southampton
- Southampton
| | - Peter N. Horton
- UK National Crystallographic Service
- Chemistry
- Faculty of Natural and Environmental Sciences
- University of Southampton
- Southampton
| | - Alex Hamilton
- Biomolecular Sciences Research Centre (BMRC) and Department of Biosciences and Chemistry
- Faculty of Health and Wellbeing
- Sheffield Hallam University
- Sheffield
- UK
| | - Christopher J. Whiteoak
- Biomolecular Sciences Research Centre (BMRC) and Department of Biosciences and Chemistry
- Faculty of Health and Wellbeing
- Sheffield Hallam University
- Sheffield
- UK
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37
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Altahan MA, Beckett MA, Coles SJ, Horton PN. Oxidopolyborate anions templated by transition-metal complex cations: Self-assembled syntheses and structural studies (XRD) of [Co(NH3)6]2[B4O5(OH)4]3·11H2O, [Ni(phen)3][B7O9(OH)5].9.5H2O and [Zn(dac)2(H2O)2][B7O9(OH)5]·H2O. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2019.127071] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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38
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Beckett MA, Meena BI, Rixon TA, Coles SJ, Horton PN. Pentaborate(1-) Salts and a Tetraborate(2-) Salt Derived from C 2- or C 3-Linked Bis(alkylammonium) Dications: Synthesis, Characterization, and Structural (XRD) Studies. Molecules 2019; 25:molecules25010053. [PMID: 31877919 PMCID: PMC6982793 DOI: 10.3390/molecules25010053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 12/18/2019] [Accepted: 12/21/2019] [Indexed: 11/26/2022]
Abstract
The synthesis of a number of pentaborate(1-) salts from cations arising from N-substituted α,α-, α,β-, and α,γ-diaminoalkanes has been attempted in aqueous solution from B(OH)3 and the appropriate diammine in a 10:1 ratio. Despite relatively mild work-up conditions the pentaborate(1-) salts prepared were not always as anticipated and the following compounds were isolated in good yield: [Me2NH(CH2)2NHMe2][B5O6(OH)4]2 (1), [Et2NH(CH2)2NHEt2][B5O6(OH)4]2 (2), [Et2NH2][B5O6(OH)4] (3), [Me2NH2][B5O6(OH)4] (4), [Me2NH(CH2)3NHMe2][B5O6(OH)4]2 (5), [Et2NH(CH2)3NHEt2][B5O6(OH)4]2 (6), [Me3NCH2CH=CH2][B5O6(OH)4] (7), and [Me3N(CH2)3NMe3] [B5O6(OH)4]2.0.5H2O (8). The tetraborate(2-) salt, [Me3N(CH2)2NMe3][B4O5(OH)4].2B(OH)3.2H2O (9) was obtained in moderate yield (41%) from a 3:1 reaction of B(OH)3 with [Me3N(CH2)2NMe3](OH)2. All compounds were characterized by spectroscopy (1H, 11B, 13C NMR and IR) and thermal gravimetric analysis (TGA). BET analysis on materials derived thermally from selected samples (1, 2, 6, 7) all had porosities of < 1 m2/g, demonstrating that they were non-porous. Single-crystal XRD structures were obtained for 2, 3, 7, 8 and 9 and all contain extensive H-bonded polyborate lattices.
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Affiliation(s)
- Michael A. Beckett
- School of Natural Sciences, Bangor University, Bangor LL57 2UW, UK; (B.I.M.); (T.A.R.)
- Correspondence: ; Tel.: +44-1248-382-378
| | - Bashdar I. Meena
- School of Natural Sciences, Bangor University, Bangor LL57 2UW, UK; (B.I.M.); (T.A.R.)
| | - Thomas A. Rixon
- School of Natural Sciences, Bangor University, Bangor LL57 2UW, UK; (B.I.M.); (T.A.R.)
| | - Simon J. Coles
- Chemistry Department, University of Southampton, Southampton SO17 1BJ, UK; (S.J.C.); (P.N.H.)
| | - Peter N. Horton
- Chemistry Department, University of Southampton, Southampton SO17 1BJ, UK; (S.J.C.); (P.N.H.)
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39
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Beckett MA, Coles SJ, Horton PN, Rixon TA. Synthesis and XRD study of an C 2-linked bis(quaternary ammonium) pentaborate: [Me 3NCH 2CH 2NMe 3][B 5O 6(OH) 4] 2. PHOSPHORUS SULFUR 2019. [DOI: 10.1080/10426507.2019.1631308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
| | - Simon J. Coles
- Faculty of Engineering and the Environment, Chemistry, University of Southampton, Southampton, UK
| | - Peter N. Horton
- Faculty of Engineering and the Environment, Chemistry, University of Southampton, Southampton, UK
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40
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Phillips KA, Stonelake TM, Horton PN, Coles SJ, Hallett AJ, O'Kell SP, Beames JM, Pope SJ. Dual visible/NIR emission from organometallic iridium(III) complexes. J Organomet Chem 2019. [DOI: 10.1016/j.jorganchem.2019.04.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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41
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Fugu MB, Ellaby RJ, O'Connor HM, Pitak MB, Klooster W, Horton PN, Coles SJ, Al-Mashhadani MH, Perepichka IF, Brechin EK, Jones LF. Mono- and ditopic hydroxamate ligands towards discrete and extended network architectures. Dalton Trans 2019; 48:10180-10190. [PMID: 31187830 DOI: 10.1039/c9dt01531k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A family of mono- and ditopic hydroxamic acids has been employed in the synthesis and structural and physical characterisation of discrete (0D) and (1- and 2-D) extended network coordination complexes. Examples of the latter include the 1-D coordination polymer {[Zn(ii)(L3H)2]·2MeOH}n (5; L3H2 = 2-(methylamino)phenylhydroxamic acid) and the 2-D extended network {[Cu(ii)(L2H)(H2O)(NO3)]·H2O}n (5; L2H2 = 4-amino-2-(acetoxy)phenylhydroxamic acid). The 12-MC-4 metallacrown [Cu(ii)5(L4H)4(MeOH)2(NO3)2]·3H2O·4MeOH (7) represents the first metal complex constructed using the novel ligand N-hydroxy-2-[(2-hydroxy-3-methoxybenzyl)amino]benzamide (L4H3). Variable temperature magnetic susceptibility studies confirm strong antiferromagnetic exchange between the Cu(ii) centres in 7. Coordination polymer 5 shows photoluminescence in the blue region (λPL∼ 421-450 nm) with a bathochromic shift of the emission (∼15-30 nm) from solution to the solid state.
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Affiliation(s)
- Mohammed B Fugu
- School of Natural Sciences, Bangor University, Bangor, Wales LL57 2DG, UK.
| | - Rebecca J Ellaby
- School of Natural Sciences, Bangor University, Bangor, Wales LL57 2DG, UK.
| | - Helen M O'Connor
- EaStCHEM School of Chemistry, David Brewster Road, University of Edinburgh, Edinburgh, Scotland EH9 3FJ, UK
| | - Mateusz B Pitak
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, England, SO17 1BJ, UK
| | - Wim Klooster
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, England, SO17 1BJ, UK
| | - Peter N Horton
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, England, SO17 1BJ, UK
| | - Simon J Coles
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, England, SO17 1BJ, UK
| | - Mohammed H Al-Mashhadani
- School of Natural Sciences, Bangor University, Bangor, Wales LL57 2DG, UK. and Chemistry Department, College of Science, Al-Nahrain University, Baghdad, Iraq
| | - Igor F Perepichka
- Shaanxi Institute of Flexible Electronics, Northwestern Polytechnical University, 127 West Youyi Road, Xi'an 710072, Shaanxi, China
| | - Euan K Brechin
- EaStCHEM School of Chemistry, David Brewster Road, University of Edinburgh, Edinburgh, Scotland EH9 3FJ, UK
| | - Leigh F Jones
- School of Natural Sciences, Bangor University, Bangor, Wales LL57 2DG, UK.
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42
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Child SN, Raychev R, Moss N, Howchen B, Horton PN, Prior CC, Oganesyan VS, Fielden J. Cobalt-based molecular electrocatalysis of nitrile reduction: evolving sustainability beyond hydrogen. Dalton Trans 2019; 48:9576-9580. [PMID: 31184345 DOI: 10.1039/c9dt00773c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Two new cobalt bis-iminopyridines, [Co(DDP)(H2O)2](NO3)2 (1, DDP = cis-[1,3-bis(2-pyridinylenamine)] cyclohexane) and [Co(cis-DDOP)(NO3)](NO3) (2, cis-DDOP = cis-3,5-bis[(2-Pyridinyleneamin]-trans-hydroxycyclohexane) electrocatalyse the 4-proton, 4-electron reduction of acetonitrile to ethylamine. For 1, this reduction occurs in preference to reduction of protons to H2. A coordinating hydroxyl proton relay in 2 reduces the yield of ethylamine and biases the catalytic system back towards H2.
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Affiliation(s)
- Simon N Child
- School of Chemistry, University of East Anglia, Norwich, NR4 7TJ, UK.
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43
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Christensen J, Horton PN, Bury CS, Dickerson JL, Taberman H, Garman EF, Coles SJ. Radiation damage in small-molecule crystallography: fact not fiction. IUCrJ 2019; 6:703-713. [PMID: 31316814 PMCID: PMC6608633 DOI: 10.1107/s2052252519006948] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 05/14/2019] [Indexed: 05/29/2023]
Abstract
Traditionally small-molecule crystallographers have not usually observed or recognized significant radiation damage to their samples during diffraction experiments. However, the increased flux densities provided by third-generation synchrotrons have resulted in increasing numbers of observations of this phenomenon. The diversity of types of small-molecule systems means it is not yet possible to propose a general mechanism for their radiation-induced sample decay, however characterization of the effects will permit attempts to understand and mitigate it. Here, systematic experiments are reported on the effects that sample temperature and beam attenuation have on radiation damage progression, allowing qualitative and quantitative assessment of their impact on crystals of a small-molecule test sample. To allow inter-comparison of different measurements, radiation-damage metrics (diffraction-intensity decline, resolution fall-off, scaling B-factor increase) are plotted against the absorbed dose. For ease-of-dose calculations, the software developed for protein crystallography, RADDOSE-3D, has been modified for use in small-molecule crystallography. It is intended that these initial experiments will assist in establishing protocols for small-molecule crystallographers to optimize the diffraction signal from their samples prior to the onset of the deleterious effects of radiation damage.
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Affiliation(s)
- Jeppe Christensen
- Diamond Light Source Ltd, Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
- National Crystallography Service, School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Peter N. Horton
- National Crystallography Service, School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Charles S. Bury
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Joshua L. Dickerson
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Helena Taberman
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Elspeth F. Garman
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Simon J. Coles
- National Crystallography Service, School of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, UK
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44
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Altahan MA, Beckett MA, Coles SJ, Horton PN. Copper(2+) complexes of hydroxyoxidopolyborates: Synthesis and characterization of [Cu(MeNHCH 2CH 2NMeH) 2(H 2O) 2][B 5O 6(OH) 4] 2.2B(OH) 3. PHOSPHORUS SULFUR 2019. [DOI: 10.1080/10426507.2019.1631307] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
| | | | - Simon J. Coles
- Faculty of Engineering and the Environment, Chemistry, University of Southampton, Southampton, UK
| | - Peter N. Horton
- Faculty of Engineering and the Environment, Chemistry, University of Southampton, Southampton, UK
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45
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Altahan MA, Beckett MA, Coles SJ, Horton PN. Copper(2+) Complexes of Hydroxyoxidoborates. Synthesis and Characterization of Two Clusters Containing the Hexaborate(2−) Ligand: [Cu(NH2CH2CH2NEt2){B6O7(OH)6}]·5H2O and [Cu(NH3)2{B6O7(OH)6}]·2H2O. J CLUST SCI 2019. [DOI: 10.1007/s10876-019-01519-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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46
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Arthurs RA, Hughes DL, Horton PN, Coles SJ, Richards CJ. Application of Transmetalation to the Synthesis of Planar Chiral and Chiral-at-Metal Iridacycles. Organometallics 2019. [DOI: 10.1021/acs.organomet.8b00905] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Ross A. Arthurs
- School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, U.K
| | - David L. Hughes
- School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, U.K
| | - Peter N. Horton
- EPSRC National Crystallography Service, School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, U.K
| | - Simon J. Coles
- EPSRC National Crystallography Service, School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, U.K
| | - Christopher J. Richards
- School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, U.K
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47
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Slater-Parry ME, Durrant JP, Howells JM, Pitak MB, Horton PN, Klooster WT, Coles SJ, O'Connor HM, Brechin EK, Barra AL, Jones LF. Crowding out: ligand modifications and their structure directing effects on brucite-like {M x(μ 3-OH) y} (M = Co(ii), Ni(ii)) core growth within polymetallic cages. Dalton Trans 2019; 48:1477-1488. [PMID: 30632582 DOI: 10.1039/c8dt04229b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Previous employment of the ligands 2-methoxy-6-[(methylimino)methyl]phenol (L1H) and 2-methoxy-6-[(phenylimino)methyl]phenol (L2H) has resulted in the self-assembly of pseudo metallocalix[6]arene complexes of general formulae: [M7(μ3-OH)6(Lx)6](NO3)y (M = Ni(ii), x = 1, y = 2 (1) and Co(ii/iii), x = 2, y = 3 (2)). Extrapolating upon this work, we report the coordination chemistry of ligands 2-methoxy-6-{[(2-methoxyphenyl)imino]methyl}phenol (L3H), 2-[(benzylimino)methyl]-6-methoxyphenol (L4H), 2-[(benzylamino)methyl]-6-methoxyphenol (L5H) and 2-[(benzylamino)methyl]-4-bromo-6-methoxyphenol (L6H), whose structures are modifications of ligands L1-2H. These ligands are employed in the synthesis and characterisation of the dimetallic complex [Ni(ii)2(L3)3(H2O)](NO3)·2H2O·3MeOH (3); the monometallic complexes [Ni(ii)(L4)2] (4) and [Co(iii)(L4)3]·H2O·MeOH (5a); and the tetranuclear pseudo metallocalix[4]arene complexes: [(NO3)⊂Co(ii)4(μ3-OH)2(L5)4(H2O)2](NO3)·H2O (6), [(NO3)⊂Ni(ii)4(μ3-OH)2(L5)4(H2O)2](NO3)·H2O (7) and [Ni(ii)4(μ3-OH)2(L6)4(NO3)2]·MeCN (8). The tetrametallic 'butterfly' core topologies in 6-8 are discussed with respect to their structural and topological relationship with their heptanuclear [M7] (M = Co(ii), Ni(ii)) pseudo metallocalix[6]arene ancestors (1 and 2).
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Affiliation(s)
| | - James P Durrant
- School of Natural Sciences, Bangor University, Bangor, Wales, LL57 2DG, UK.
| | - Joshua M Howells
- School of Natural Sciences, Bangor University, Bangor, Wales, LL57 2DG, UK.
| | - Mateusz B Pitak
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, England SO17 1BJ, UK
| | - Peter N Horton
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, England SO17 1BJ, UK
| | - Wim T Klooster
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, England SO17 1BJ, UK
| | - Simon J Coles
- UK National Crystallographic Service, Chemistry, Faculty of Natural and Environmental Sciences, University of Southampton, England SO17 1BJ, UK
| | - Helen M O'Connor
- EaStCHEM School of Chemistry, David Brewster Road, University of Edinburgh, Edinburgh, Scotland EH9 3FJ, UK
| | - Euan K Brechin
- EaStCHEM School of Chemistry, David Brewster Road, University of Edinburgh, Edinburgh, Scotland EH9 3FJ, UK
| | - Anne-Laure Barra
- LNCMI-CNRS, Universite Grenoble-Alpes, Avenue des Martyrs, Grenoble, France
| | - Leigh F Jones
- School of Natural Sciences, Bangor University, Bangor, Wales, LL57 2DG, UK.
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48
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Yan B, Horton PN, Russell AE, Wedge CJ, Weston SC, Grossel MC. Crown ether alkali metal TCNQ complexes revisited – the impact of smaller cation complexes on their solid-state architecture and properties. CrystEngComm 2019. [DOI: 10.1039/c9ce00234k] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Water molecules play a key structure-organising role in the crystallisation of 15-crown-5 complexes of lithium and sodium TCNQ in the presence of excess TCNQ0.
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Affiliation(s)
- Bingjia Yan
- School of Chemistry
- University of Southampton
- Southampton
- UK
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49
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Geoghegan BL, Phonsri W, Horton PN, Orton JB, Coles SJ, Murray KS, Cragg PJ, Dymond MK, Gass IA. Hysteretic thermal spin-crossover in heteroleptic Fe(ii) complexes using alkyl chain substituted 2,2′-dipyridylamine ligands. Dalton Trans 2019; 48:17340-17348. [DOI: 10.1039/c9dt03412a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The complexes trans-[FeII(LC4)2(NCS)2] (1C4) and trans-[FeII(LC10)2(NCS)2] (1C10) undergo thermally hysteretic spin-crossover with T1/2 = 127.5 K and 119.0 K respectively.
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Affiliation(s)
- Blaise L. Geoghegan
- School of Pharmacy and Biomolecular Sciences
- Huxley Building
- University of Brighton
- Brighton
- UK
| | - Wasinee Phonsri
- School of Chemistry
- Building 23
- Monash University
- Clayton
- Australia
| | - Peter N. Horton
- The UK National Crystallography Service
- School of Chemistry
- University of Southampton
- Southampton
- UK
| | - James B. Orton
- The UK National Crystallography Service
- School of Chemistry
- University of Southampton
- Southampton
- UK
| | - Simon J. Coles
- The UK National Crystallography Service
- School of Chemistry
- University of Southampton
- Southampton
- UK
| | - Keith S. Murray
- School of Chemistry
- Building 23
- Monash University
- Clayton
- Australia
| | - Peter J. Cragg
- School of Pharmacy and Biomolecular Sciences
- Huxley Building
- University of Brighton
- Brighton
- UK
| | - Marcus K. Dymond
- School of Pharmacy and Biomolecular Sciences
- Huxley Building
- University of Brighton
- Brighton
- UK
| | - Ian A. Gass
- School of Pharmacy and Biomolecular Sciences
- Huxley Building
- University of Brighton
- Brighton
- UK
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50
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Groves LM, Williams CF, Hayes AJ, Ward BD, Isaacs MD, Symonds NO, Lloyd D, Horton PN, Coles SJ, Pope SJA. Fluorescent functionalised naphthalimides and their Au(i)–NHC complexes for potential use in cellular bioimaging. Dalton Trans 2019; 48:1599-1612. [DOI: 10.1039/c8dt04069a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A series of fluorescent gold(i)–NHC complexes have been developed and investigated as cell imaging agents.
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Affiliation(s)
- Lara M. Groves
- School of Chemistry
- Main Building
- Cardiff University
- Cardiff CF10 3AT
- UK
| | | | - Anthony J. Hayes
- School of Biosciences (and Bio-imaging Research Hub)
- Sir Martin Evans Building
- Cardiff University
- Cardiff
- UK CF19 3AX
| | - Benjamin D. Ward
- School of Chemistry
- Main Building
- Cardiff University
- Cardiff CF10 3AT
- UK
| | - Marc D. Isaacs
- School of Biosciences (and Bio-imaging Research Hub)
- Sir Martin Evans Building
- Cardiff University
- Cardiff
- UK CF19 3AX
| | - Nadine O. Symonds
- School of Chemistry
- Main Building
- Cardiff University
- Cardiff CF10 3AT
- UK
| | - David Lloyd
- School of Biosciences (and Bio-imaging Research Hub)
- Sir Martin Evans Building
- Cardiff University
- Cardiff
- UK CF19 3AX
| | - Peter N. Horton
- UK National Crystallographic Service
- Chemistry
- Faculty of Natural and Environmental Sciences
- University of Southampton
- Southampton
| | - Simon J. Coles
- UK National Crystallographic Service
- Chemistry
- Faculty of Natural and Environmental Sciences
- University of Southampton
- Southampton
| | - Simon J. A. Pope
- School of Chemistry
- Main Building
- Cardiff University
- Cardiff CF10 3AT
- UK
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