51
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Abazari R, Amani-Ghadim AR, Slawin AMZ, Carpenter-Warren CL, Kirillov AM. Non-Calcined Layer-Pillared Mn 0.5Zn 0.5 Bimetallic-Organic Framework as a Promising Electrocatalyst for Oxygen Evolution Reaction. Inorg Chem 2022; 61:9514-9522. [PMID: 35699592 PMCID: PMC9775468 DOI: 10.1021/acs.inorgchem.2c00542] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Electrocatalytic generation of oxygen is of great significance for sustainable, clean, and efficient energy production. Multiple electron transfer in oxygen evolution reaction (OER) and its slow kinetics represent a serious hedge for efficient water splitting, requiring the design and development of advanced electrocatalysts with porous structures, high surface areas, abundant electroactive sites, and low overpotentials. These requisites are common for metal-organic frameworks (MOFs) and derived materials that are promising electrocatalysts for OER. The present work reports on the synthesis and full characterization of a heteroleptic 3D MOF, [Zn2(μ4-odba)2(μ-bpdh)]n·nDMF (Zn-MUM-1), assembled from 4,4'-oxydibenzoic acid and 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (bpdh). Besides, a series of heterometallic MnZn-MUM-1 frameworks (abbreviated as Mn0.5Zn0.5-MUM-1, Mn0.66Zn0.33-MUM-1, and Mn0.33Zn0.66-MUM-1) was also prepared, characterized, and used for the fabrication of working electrodes based on Ni foam (NF), followed by their exploration in OER. These noble-metal-free and robust electrocatalysts are stable and do not require pyrolysis or calcination while exhibiting better electrocatalytic performance than the parent Zn-MUM-1/NF electrode. The experimental results show that the Mn0.5Zn0.5-MUM-1/NF electrocatalyst features the best OER activity with a low overpotential (253 mV at 10 mA cm-2) and Tafel slope (73 mV dec-1) as well as significant stability after 72 h or 6000 cycles. These excellent results are explained by a synergic effect of two different metals present in the Mn-Zn MOF as well as improved charge and ion transfer, conductivity, and stability characteristics. The present study thus widens the application of heterometallic MOFs as prospective and highly efficient electrocatalysts for OER.
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52
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Ibrahim ABM, Mahmoud GA, Cordes DB, Slawin AMZ. Pb (II) and Hg (II) Thiosemicarbazones for Inhibiting the Broad‐Spectrum Pathogen
Cladosporium sphaerospermum
ASU18 (MK387875) and Altering Its Antioxidant System. Appl Organomet Chem 2022. [DOI: 10.1002/aoc.6798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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53
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Bitai J, Nimmo AJ, Slawin AMZ, Smith AD. Cooperative Palladium/Isothiourea Catalyzed Enantioselective Formal (3+2) Cycloaddition of Vinylcyclopropanes and α,β-Unsaturated Esters. Angew Chem Int Ed Engl 2022; 61:e202202621. [PMID: 35389553 PMCID: PMC9324207 DOI: 10.1002/anie.202202621] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Indexed: 12/15/2022]
Abstract
A protocol for the enantioselective synthesis of substituted vinylcyclopentanes has been realised using cooperative palladium and isothiourea catalysis. Treatment of vinylcyclopropanes with Pd(PPh3 )4 generates a zwitterionic π-allyl palladium intermediate that intercepts a catalytically generated α,β-unsaturated acyl ammonium species prepared from the corresponding α,β-unsaturated para-nitrophenyl ester and the isothiourea (R)-BTM. Intermolecular formal (3+2) cycloaddition between these reactive intermediates generates functionalised cyclopentanes in generally good yields and excellent diastereo- and enantiocontrol (up to >95 : 5 dr, 97 : 3 er), with the use of LiCl as an additive proving essential for optimal stereocontrol. To the best of our knowledge a dual transition metal/organocatalytic process involving α,β-unsaturated acyl ammonium intermediates has not been demonstrated previously.
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54
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Wu J, Young CM, Watts AA, Slawin AMZ, Boyce GR, Bühl M, Smith AD. Isothiourea-Catalyzed Enantioselective Michael Addition of Malonates to α,β-Unsaturated Aryl Esters. Org Lett 2022; 24:4040-4045. [PMID: 35652512 PMCID: PMC9278409 DOI: 10.1021/acs.orglett.2c01486] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
An enantioselective Michael addition of malonates to α,β-unsaturated para-nitrophenyl esters was achieved using the Lewis basic isothiourea HyperBTM, giving excellent levels of product enantioselectivity (up to >99:1 enantiomeric ratio) in good yields and with complete regioselectivity (>20:1 regioselectivity ratio) in the presence of alternative (phenyl ketone and ethyl ester) Michael acceptors. Density functional theory calculations indicate that N-acylation is rate-limiting. This constitutes a rare example of a highly enantioselective addition of simple, readily available malonates to α,β-unsaturated esters.
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55
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Klee PS, Hirano Y, Cordes DB, Slawin AMZ, Payne JL. Synthesis, Structure, and Tunability of Zero-Dimensional Organic-Inorganic Metal Halides Utilizing the m-Xylylenediammonium Cation: MXD 2PbI 6, MXDBiI 5, and MXD 3Bi 2Br 12·2H 2O. CRYSTAL GROWTH & DESIGN 2022; 22:3815-3823. [PMID: 36160302 PMCID: PMC9490867 DOI: 10.1021/acs.cgd.2c00187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 04/15/2022] [Indexed: 06/16/2023]
Abstract
Over the past decade, the efficiency of photovoltaic devices based on CH3NH3PbI3 have dramatically increased. This has driven research efforts in all areas, from the discovery of materials to film processing to long-term device stability studies. Here, we report the synthesis and structure of three new "zero dimensional" organic-inorganic metal halides which use the meta-xylylenediammonium (MXD) cation: MXD2PbI6, MXDBiI5, and (MXD)3Bi2Br12·2H2O. The different structures of the new materials lead to compounds with a range of band gaps with MXDBiI5 having the lowest at 2.15 eV. We have explored the tunabilty of MXDBiI5 through halide substitution by preparing a series of samples with composition MXDBiI5-x Br x and determined the halide content using energy dispersive X-ray spectroscopy. A large range of solid solution is obtained in MXDBiI5-x Br x , resulting in the formation of single-phase materials for bromine contents from x = 0 to 3.71 (iodine contents from 1.29 to 5). This highlights the fact that zero-dimensional organic-inorganic halides are highly tunable, in a similar manner to the higher-dimensional perovskite counterparts. Such new materials open up the opportunity for further studies of the physics and optoelectronic properties of these materials.
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56
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Ibrahim S, Mohsin Saleem M, Imran M, Ali Shah W, Cordes D, M. Z. Slawin A, Arif Nadeem M. A two-dimensional manganese-containing coordination polymer for efficient catalysis of the oxygen evolution. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2022.121030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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57
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Bell G, Fyfe JWB, Israel EM, Slawin AMZ, Campbell M, Watson AJB. Synthesis of 2-BMIDA Indoles via Heteroannulation: Applications in Drug Scaffold and Natural Product Synthesis. Org Lett 2022; 24:3024-3027. [PMID: 35426314 PMCID: PMC9062883 DOI: 10.1021/acs.orglett.2c00959] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Indexed: 12/12/2022]
Abstract
A Pd-catalyzed heteroannulation approach for the synthesis of C2 borylated indoles is reported. The process allows access to highly functionalized 2-borylated indole scaffolds with complete control of regioselectivity. The utility of the process is demonstrated in the synthesis of borylated sulfa drugs and in the concise synthesis of the Aspidosperma alkaloid Goniomitine.
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Bitai J, Nimmo AJ, Slawin AMZ, Smith AD. Cooperative Palladium/Isothiourea Catalyzed Enantioselective Formal (3+2) Cycloaddition of Vinylcyclopropanes and a,b‐Unsaturated Esters. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202202621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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59
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Aitken RA, Harper AD, Inwood RA, Slawin AMZ. Access to Diarylmethanols by Wittig Rearrangement of ortho-, meta-, and para-Benzyloxy- N-Butylbenzamides. J Org Chem 2022; 87:4692-4701. [PMID: 35286089 PMCID: PMC9007461 DOI: 10.1021/acs.joc.1c03160] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
The N-butyl amide
group, CONHBu, has been found
to be an effective promoter of the [1,2]-Wittig rearrangement of aryl
benzyl ethers and thus allow the two-step synthesis of isomerically
pure substituted diarylmethanols starting from simple hydroxybenzoic
acid derivatives. The method is compatible with a wide range of functional
groups including methyl, methoxy, and fluoro, although not with nitro
and, unexpectedly, is applicable to meta as well
as ortho and para isomeric series.
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McLean LA, Ashford MW, Fyfe JWB, Slawin AMZ, Leach AG, Watson AJB. Asymmetric Synthesis of Heterocyclic Chloroamines and Aziridines by Enantioselective Protonation of Catalytically Generated Enamines. Chemistry 2022; 28:e202200060. [PMID: 35133031 PMCID: PMC9306946 DOI: 10.1002/chem.202200060] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Indexed: 02/01/2023]
Abstract
We report a method for the synthesis of chiral vicinal chloroamines via asymmetric protonation of catalytically generated prochiral chloroenamines using chiral Brønsted acids. The process is highly enantioselective, with the origin of asymmetry and catalyst substituent effects elucidated by DFT calculations. We show the utility of the method as an approach to the synthesis of a broad range of heterocycle-substituted aziridines by treatment of the chloroamines with base in a one-pot process, as well as the utility of the process to allow access to vicinal diamines.
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61
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Han C, Bradford AJ, McNulty JA, Zhang W, Halasyamani PS, Slawin AMZ, Morrison FD, Lee SL, Lightfoot P. Polarity and Ferromagnetism in Two-Dimensional Hybrid Copper Perovskites with Chlorinated Aromatic Spacers. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2022; 34:2458-2467. [PMID: 35431437 PMCID: PMC9008537 DOI: 10.1021/acs.chemmater.2c00107] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/08/2022] [Indexed: 06/13/2023]
Abstract
Two-dimensional (2D) organic-inorganic hybrid copper halide perovskites have drawn tremendous attention as promising multifunctional materials. Herein, by incorporating ortho-, meta-, and para-chlorine substitutions in the benzylamine structure, we first report the influence of positional isomerism on the crystal structures of chlorobenzylammonium copper(II) chloride perovskites A2CuCl4. 2D polar ferromagnets (3-ClbaH)2CuCl4 and (4-ClbaH)2CuCl4 (ClbaH+ = chlorobenzylammonium) are successfully obtained. They both adopt a polar monoclinic space group Cc at room temperature, displaying significant differences in crystal structures. In contrast, (2-ClbaH)2CuCl4 adopts a centrosymmetric space group P 21/ c at room temperature. This associated structural evolution successfully enhances the physical properties of the two polar compounds with high thermal stability, discernible second harmonic generation (SHG) signals, ferromagnetism, and narrow optical band gaps. These findings demonstrate that the introduction of chlorine atoms into the interlayer organic species is a powerful tool to tune crystal symmetries and physical properties, and this inspires further exploration of designing high-performance multifunctional copper-based materials.
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62
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Hall D, Stavrou K, Duda E, Danos A, Bagnich S, Warriner S, Slawin AMZ, Beljonne D, Köhler A, Monkman A, Olivier Y, Zysman-Colman E. Diindolocarbazole - achieving multiresonant thermally activated delayed fluorescence without the need for acceptor units. MATERIALS HORIZONS 2022; 9:1068-1080. [PMID: 35067689 DOI: 10.1039/d1mh01383a] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In this work we present a new multi-resonance thermally activated delayed fluorescence (MR-TADF) emitter paradigm, demonstrating that the structure need not require the presence of acceptor atoms. Based on an in silico design, the compound DiICzMes4 possesses a red-shifted emission, enhanced photoluminescence quantum yield, and smaller singlet-triplet energy gap, ΔEST, than the parent indolocarbazole that induces MR-TADF properties. Coupled cluster calculations accurately predict the magnitude of the ΔEST when the optimized singlet and triplet geometries are used. Slow yet optically detectable reverse intersystem crossing contributes to low efficiency in organic light-emitting diodes using DiICzMes4 as the emitter. However, when used as a terminal emitter in combination with a TADF assistant dopant within a hyperfluorescence device architecture, maximum external quantum efficiencies of up to 16.5% were achieved at CIE (0.15, 0.11). This represents one of the bluest hyperfluorescent devices reported to date. Simultaneously, recognising that MR-TADF emitters do not require acceptor atoms reveals an unexplored frontier in materials design, where yet greater performance may yet be discovered.
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63
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Han C, McNulty JA, Bradford AJ, Slawin AMZ, Morrison FD, Lee SL, Lightfoot P. Polar Ferromagnet Induced by Fluorine Positioning in Isomeric Layered Copper Halide Perovskites. Inorg Chem 2022; 61:3230-3239. [PMID: 35138839 PMCID: PMC9007457 DOI: 10.1021/acs.inorgchem.1c03726] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We present the influence of positional isomerism on the crystal structure of fluorobenzylammonium copper(II) chloride perovskites A2CuCl4 by incorporating ortho-, meta-, and para-fluorine substitution in the benzylamine structure. Two-dimensional (2D) polar ferromagnet (3-FbaH)2CuCl4 (3-FbaH+ = 3-fluorobenzylammonium) is successfully obtained, which crystallizes in a polar orthorhombic space group Pca21 at room temperature. In contrast, both (2-FbaH)2CuCl4 (2-FbaH+ = 2-fluorobenzylammonium) and (4-FbaH)2CuCl4 (4-FbaH+ = 4-fluorobenzylammonium) crystallize in centrosymmetric space groups P21/c and Pnma at room temperature, respectively, displaying significant differences in crystal structures. These differences indicate that the position of the fluorine atom is a driver for the polar behavior in (3-FbaH)2CuCl4. Preliminary magnetic measurements confirm that these three perovskites possess dominant ferromagnetic interactions within the inorganic [CuCl4]∞ layers. Therefore, (3-FbaH)2CuCl4 is a polar ferromagnet, with potential as a type I multiferroic. This work is expected to promote further development of high-performance 2D copper(II) halide perovskite multiferroic materials.
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64
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Xiao G, Su G, Slawin AMZ, Westwood N. From Biomass to the Karrikins
via
Selective Catalytic Oxidation of Hemicellulose‐Derived Butyl Xylosides and Glucosides. European J Org Chem 2022. [DOI: 10.1002/ejoc.202101308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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65
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Duda E, Hall D, Bagnich S, Carpenter-Warren CL, Saxena R, Wong MY, Cordes DB, Slawin AMZ, Beljonne D, Olivier Y, Zysman-Colman E, Köhler A. Enhancing Thermally Activated Delayed Fluorescence by Fine-Tuning the Dendron Donor Strength. J Phys Chem B 2022; 126:552-562. [PMID: 34995068 DOI: 10.1021/acs.jpcb.1c05749] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Thermally activated delayed fluorescence (TADF) relies on a small energy gap between the emissive singlet and the nonemissive triplet state, obtained by reducing the wave function overlap between donor and acceptor moieties. Efficient emission, however, requires maintaining a good oscillator strength, which is itself based on sufficient overlap of the wave functions between donor and acceptor moieties. We demonstrate an approach to subtly fine-tune the required wave function overlap by employing donor dendrons of changing functionality. We use a carbazolyl-phthalonitrile based donor-acceptor core (2CzPN) as a reference emitter and progressively localize the hole density through substitution at the 3,6-positions of the carbazole donors (Cz) with further carbazole, (4-tert-butylphenyl)amine (tBuDPA), and phenoxazine (PXZ). Using detailed photoluminescence studies, complemented with density functional theory (DFT) calculations, we show that this approach permits a gradual decrease of the singlet-triplet gap, ΔEST, from 300 to around 10 meV in toluene, yet we also demonstrate why a small ΔEST alone is not enough. While sufficient oscillator strength is maintained with the Cz- and tBuDPA-based donor dendrons, this is not the case for the PXZ-based donor dendron, where the wave function overlap is reduced too strongly. Overall, we find the donor dendron extension approach allows successful fine-tuning of the emitter photoluminescence properties.
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66
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Smith SM, Greenhalgh MD, Feoktistova T, Walden DM, Taylor JE, Cordes DB, Slawin AMZ, Cheong PH, Smith AD. Scope, Limitations and Mechanistic Analysis of the HyperBTM‐Catalyzed Acylative Kinetic Resolution of Tertiary Heterocyclic Alcohols**. European J Org Chem 2022. [DOI: 10.1002/ejoc.202101111] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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67
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Radiush EA, Pritchina EA, Chulanova EA, Dmitriev AA, Bagryanskaya IY, Slawin AMZ, Woollins JD, Gritsan NP, Zibarev AV, Semenov NA. Chalcogen-bonded donor–acceptor complexes of 5,6-dicyano[1,2,5]selenadiazolo[3,4- b]pyrazine with halide ions. NEW J CHEM 2022. [DOI: 10.1039/d2nj02345h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
With halides X− (X = Cl, Br, I) 5,6-dicyano-[1,2,5]selenadiazolo[3,4-b]pyrazine 1 forms chalcogen-bonded complexes [1–X]− structurally defined by XRD. UV/Vis spectra of [1–X]− feature red-shifted charge-transfer bands in the Vis part.
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68
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Yu C, Piscelli BA, Maharik NA, Cordes DB, Slawin AMZ, Cormanich RA, O'Hagan D. Unexpected triaxial preferences in some all- syn 1,3,5-trifluorocyclohexanes. Chem Commun (Camb) 2022; 58:12855-12858. [DOI: 10.1039/d2cc05058g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Theory and solution NMR indicate that all-syn 1,3,5-trifluorocyclohexane adopts the expected tri-equatorial conformation, however in the solid state the more polar triaxial conformation is observed.
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69
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Aitken RA, Harper AD, Slawin AMZ. Rationalisation of Patterns of Competing Reactivity by X-ray Structure Determination: Reaction of Isomeric (Benzyloxythienyl)oxazolines with a Base. Molecules 2021; 26:molecules26247690. [PMID: 34946776 PMCID: PMC8705950 DOI: 10.3390/molecules26247690] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/14/2021] [Accepted: 12/16/2021] [Indexed: 11/16/2022] Open
Abstract
Three isomeric (benzyloxythienyl)oxazolines 9, 11 and 13 have been prepared and are found, upon treatment with a strong base, to undergo either Wittig rearrangement or intramolecular attack of the benzylic anion on the oxazoline function to give products derived from cleavage of the initially formed 3-aminothienofuran products. This pattern of reactivity is directly linked to the distance between the two reactive groups as determined by X-ray diffraction, with the greatest distance in 11 leading to exclusive Wittig rearrangement, the shortest distance in 13 giving exclusively cyclisation-derived products, and the intermediate distance in 9 leading to both processes being observed. The corresponding N-butyl amides were also obtained in two cases and one of these undergoes efficient Wittig rearrangement leading to a thieno[2,3-c]pyrrolone product.
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70
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Cockram PE, Turner C, Slawin AMZ, Smith T. Convenient Synthesis of Alternatively Bridged Tryptophan Ketopiperazines and their Activities Against Trypanosomatid Parasites. ChemMedChem 2021; 17:e202100664. [PMID: 34927802 DOI: 10.1002/cmdc.202100664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 12/14/2021] [Indexed: 11/10/2022]
Abstract
There is an urgent need for the development of new treatments against trypanosomatid parasites; the causative agents of some of the most debilitating diseases in the developing world. This work targets an interesting 6-5-6-6 fused carboline scaffold, accessing a range of substituted derivatives through stereospecific intramolecular Pictet-Spengler condensation. Modification of the cyclisation conditions allowed retention of the carbamate protecting group and gave insight into the reaction mechanism. Compounds' bioactivities were measured against T. brucei, T. cruzi, L. majorand HeLa cells. We have identified promising pan-trypanocidal lead compounds based on the core scaffold, and highlight key SAR trends which will be useful for the future development of these compounds as potent trypanocidal agents.
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71
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Chalmers BA, Somisara DMUK, Surgenor BA, Athukorala Arachchige KS, Woollins JD, Bühl M, Slawin AMZ, Kilian P. Synthetic and Structural Study of peri-Substituted Phosphine-Arsines. Molecules 2021; 26:7222. [PMID: 34885804 PMCID: PMC8658757 DOI: 10.3390/molecules26237222] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/16/2021] [Accepted: 11/23/2021] [Indexed: 11/16/2022] Open
Abstract
A series of phosphorus-arsenic peri-substituted acenaphthene species have been isolated and fully characterised, including single crystal X-ray diffraction. Reactions of EBr3 (E = P, As) with iPr2PAcenapLi (Acenap = acenaphthene-5,6-diyl) afforded the thermally stable peri-substitution supported donor-acceptor complexes, iPr2PAcenapEBr23 and 4. Both complexes show a strong P→E dative interaction, as observed by X-ray crystallography and 31P NMR spectroscopy. DFT calculations indicated the unusual As∙∙∙As contact (3.50 Å) observed in the solid state structure of 4 results from dispersion forces rather than metallic interactions. Incorporation of the excess AsBr3 in the crystal structure of 3 promotes the formation of the ion separated species [iPr2PAcenapAsBr]+Br- 5. A decomposition product 6 containing the rare [As6Br8]2- heterocubane dianion was isolated and characterised crystallographically. The reaction between iPr2PAcenapLi and EtAsI2 afforded tertiary arsine (BrAcenap)2AsEt 7, which was subsequently lithiated and reacted with PhPCl2 and Ph2PCl to afford cyclic PhP(Acenap)2AsEt 8 and acyclic EtAs(AcenapPPh2)2 9.
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72
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Main RM, Cordes DB, Desai AV, Slawin AMZ, Wheatley P, Armstrong AR, Morris RE. Solvothermal Synthesis of a Novel Calcium Metal-Organic Framework: High Temperature and Electrochemical Behaviour. Molecules 2021; 26:molecules26227048. [PMID: 34834138 PMCID: PMC8623775 DOI: 10.3390/molecules26227048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/15/2021] [Accepted: 11/18/2021] [Indexed: 11/16/2022] Open
Abstract
The rapid growth in the field of metal-organic frameworks (MOFs) over recent years has highlighted their high potential in a variety of applications. For biological and environmental applications MOFs with low toxicity are vitally important to avoid any harmful effects. For this reason, Ca-based MOFs are highly desirable owing to their low cost and high biocompatibility. Useful Ca MOFs are still rare owing to the ionic character and large size of the Ca2+ ion tending to produce dense phases. Presented here is a novel Ca-based MOF containing 2,3-dihyrdoxyterephthalate (2,3-dhtp) linkers Ca(2,3-dhtp)(H2O) (SIMOF-4). The material undergoes a phase transformation on heating, which can be followed by variable temperature powder X-ray diffraction. The structure of the high temperature form was obtained using single-crystal X-ray diffraction. The electrochemical properties of SIMOF-4 were also investigated for use in a Na ion battery.
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73
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Fuentes JA, Janka ME, Rodgers J, Fontenot KJ, Bühl M, Slawin AMZ, Clarke ML. Effect of Ligand Backbone on the Selectivity and Stability of Rhodium Hydroformylation Catalysts Derived from Phospholane-Phosphites. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00540] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Clark JL, Neyyappadath RM, Yu C, Slawin AMZ, Cordes DB, O'Hagan D. Janus All-Cis 2,3,4,5,6-Pentafluorocyclohexyl Building Blocks Applied to Medicinal Chemistry and Bioactives Discovery Chemistry. Chemistry 2021; 27:16000-16005. [PMID: 34486192 PMCID: PMC9292521 DOI: 10.1002/chem.202102819] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Indexed: 12/24/2022]
Abstract
Monoalkylated derivatives of the unusually polar all-cis 2,3,4,5,6- pentafluorocyclohexyl (Janus face) motif are prepared starting from an aryl hydrogenation of 2,3,4,5,6- pentafluorophenylacetate methyl ester 15. The method used Zeng's Rh(CAAC) carbene catalyst 4 in the hydrogenation following the protocol developed by Glorius. The resultant Janus pentafluorocyclohexylacetate methyl ester 16 was converted to the corresponding alcohol 18, aldehyde 13, bromide 29 and azide 14 through functional group manipulations, and some of these building blocks were used in Ugi-multicomponent and Cu-catalysed click reactions. NBoc protected pentafluoroarylphenylalanine methyl ester 35 was also subject to an aryl hydrogenation, and then deprotection to generate the Janus face β-pentafluorocyclohexyl-alanine amino acid 15, which was incorporated into representative members of an emerging class of candidate antiviral compounds. Log P measurements demonstrate that the all-cis 2,3,4,5,6-pentafluorocyclohexyl ring system is more polar than a phenyl ring. In overview the paper introduces new building blocks containing this Janus ring and demonstrates their progression to molecules typically used in bioactives discovery programmes.
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Clark JL, Neyyappadath RM, Yu C, Slawin AMZ, Cordes DB, O'Hagan D. Corrigendum: Janus All-Cis 2,3,4,5,6-Pentafluorocyclohexyl Building Blocks Applied to Medicinal Chemistry and Bioactives Discovery Chemistry. Chemistry 2021; 27:16056. [PMID: 34714564 DOI: 10.1002/chem.202103802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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