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Wübker A, Koppe J, Bradtmüller H, Keweloh L, Pleschka D, Uhl W, Hansen MR, Eckert H. Solid-State Nuclear Magnetic Resonance Techniques for the Structural Characterization of Geminal Alane-Phosphane Frustrated Lewis Pairs and Secondary Adducts. Chemistry 2021; 27:13249-13257. [PMID: 34270155 PMCID: PMC8518393 DOI: 10.1002/chem.202102113] [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: 06/14/2021] [Indexed: 11/17/2022]
Abstract
The first comprehensive solid-state nuclear magnetic resonance (NMR) characterization of geminal alane-phosphane frustrated Lewis pairs (Al/P FLPs) is reported. Their relevant NMR parameters (isotropic chemical shifts, direct and indirect 27 Al-31 P spin-spin coupling constants, and 27 Al nuclear electric quadrupole coupling tensor components) have been determined by numerical analysis of the experimental NMR line shapes and compared with values computed from the known crystal structures by using density functional theory (DFT) methods. Our work demonstrates that the 31 P NMR chemical shifts for the studied Al/P FLPs are very sensitive to slight structural inequivalences. The 27 Al NMR central transition signals are spread out over a broad frequency range (>200 kHz), owing to the presence of strong nuclear electric quadrupolar interactions that can be well-reproduced by the static 27 Al wideband uniform rate smooth truncation (WURST) Carr-Purcell-Meiboom-Gill (WCPMG) NMR experiment. 27 Al chemical shifts and quadrupole tensor components offer a facile and clear distinction between three- and four-coordinate aluminum environments. For measuring internuclear Al⋅⋅⋅P distances a new resonance-echo saturation-pulse double-resonance (RESPDOR) experiment was developed by using efficient saturation via frequency-swept WURST pulses. The successful implementation of this widely applicable technique indicates that internuclear Al⋅⋅⋅P distances in these compounds can be measured within a precision of ±0.1 Å.
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Affiliation(s)
- Anna‐Lena Wübker
- Institut für Physikalische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Jonas Koppe
- Institut für Physikalische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Henrik Bradtmüller
- Institut für Physikalische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
- Department of Materials EngineeringVitreous Materials LaboratoryFederal University of São CarlosCP 67613565-905São CarlosSPBrazil
| | - Lukas Keweloh
- Institut für Anorganische und Analytische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Damian Pleschka
- Institut für Anorganische und Analytische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Werner Uhl
- Institut für Anorganische und Analytische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Michael Ryan Hansen
- Institut für Physikalische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
| | - Hellmut Eckert
- Institut für Physikalische Chemie WWU MünsterCorrensstraße 28/3048149MünsterGermany
- Instituto de Física de São CarlosUniversidade de São PauloSão CarlosSP13566-590Brazil
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2
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Affiliation(s)
- Anton V. Yadykov
- N. D. Zelinsky Institute of Organic ChemistryRussian Academy of Sciences 47 Leninsky prosp., 119991 Moscow Russian Federation
| | - Valerii Z. Shirinian
- N. D. Zelinsky Institute of Organic ChemistryRussian Academy of Sciences 47 Leninsky prosp., 119991 Moscow Russian Federation
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3
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Sun X, Zhu Q, Xie Z, Su W, Zhu J, Zhu C. An Unprecedented Ga/P Frustrated Lewis Pair: Synthesis, Characterization, and Reactivity. Chemistry 2019; 25:14295-14299. [DOI: 10.1002/chem.201904081] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Indexed: 11/11/2022]
Affiliation(s)
- Xiong Sun
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 P. R. China
| | - Qin Zhu
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 P. R. China
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), andDepartment of ChemistryCollege of Chemistry, and Chemical EngineeringXiamen University Xiamen 361005 P. R. China
| | - Zhuoyi Xie
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 P. R. China
| | - Wei Su
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 P. R. China
| | - Jun Zhu
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), andDepartment of ChemistryCollege of Chemistry, and Chemical EngineeringXiamen University Xiamen 361005 P. R. China
| | - Congqing Zhu
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 P. R. China
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4
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Weger M, Grötsch RK, Knaus MG, Giuman MM, Mayer DC, Altmann PJ, Mossou E, Dittrich B, Pöthig A, Rieger B. Nicht‐unschuldiger Methylen‐Linker in verbrückten Lewis‐Paar‐ Initiatoren. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201902833] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Michael Weger
- Katalysezentrum & WACKER-Lehrstuhl für Makromolekulare ChemieTechnische Universität München Lichtenbergstraße 4 85748 Garching Deutschland
| | - Raphael K. Grötsch
- Katalysezentrum & WACKER-Lehrstuhl für Makromolekulare ChemieTechnische Universität München Lichtenbergstraße 4 85748 Garching Deutschland
| | - Maximilian G. Knaus
- Katalysezentrum & WACKER-Lehrstuhl für Makromolekulare ChemieTechnische Universität München Lichtenbergstraße 4 85748 Garching Deutschland
| | - Marco M. Giuman
- Katalysezentrum & WACKER-Lehrstuhl für Makromolekulare ChemieTechnische Universität München Lichtenbergstraße 4 85748 Garching Deutschland
| | - David C. Mayer
- Katalysezentrum & Lehrstuhl für anorganische und metallorganische ChemieTechnische Universität München Lichtenbergstraße 4 85748 Garching Deutschland
| | - Philipp J. Altmann
- Katalysezentrum & Lehrstuhl für anorganische und metallorganische ChemieTechnische Universität München Lichtenbergstraße 4 85748 Garching Deutschland
| | - Estelle Mossou
- Institute Laue-Langevin 71 avenue des Martyrs CS 20156 38042 Grenoble Frankreich
- Faculty of Natural SciencesKeele University Staffordshire ST5 5BG Vereinigtes Königreich
| | - Birger Dittrich
- Anorganische Chemie und Strukturchemie 2Heinrich Heine Universität Universitätsstraße 1 40225 Düsseldorf Deutschland
| | - Alexander Pöthig
- Katalysezentrum & Lehrstuhl für anorganische und metallorganische ChemieTechnische Universität München Lichtenbergstraße 4 85748 Garching Deutschland
| | - Bernhard Rieger
- Katalysezentrum & WACKER-Lehrstuhl für Makromolekulare ChemieTechnische Universität München Lichtenbergstraße 4 85748 Garching Deutschland
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5
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Weger M, Grötsch RK, Knaus MG, Giuman MM, Mayer DC, Altmann PJ, Mossou E, Dittrich B, Pöthig A, Rieger B. Non-Innocent Methylene Linker in Bridged Lewis Pair Initiators. Angew Chem Int Ed Engl 2019; 58:9797-9801. [PMID: 31046187 DOI: 10.1002/anie.201902833] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 04/19/2019] [Indexed: 01/07/2023]
Abstract
Deprotonation usually occurs as an unwanted side reaction in the Lewis pair polymerization of Michael acceptors, for which the conjugated addition of the Lewis base to the acid-activated monomer is the commonly accepted initiation mechanism. This has also been reported for B-P-based bridged Lewis pairs (BLPs) that form macrocyclic addition products. We now show that the formerly unwanted deprotonation is the likely initiation pathway in the case of Al-P-based BLPs. In a detailed study of a series of Al-P-based BLPs, using a combination of single-crystal diffraction experiments (X-ray and neutron) and mechanistic investigations (experimental and computational), an active role of the methylene bridge was revealed, acting as a base towards the α-acidic monomers. Additionally, the polymerization studies proved a living behavior combined with significantly high activities, narrow molecular mass distributions, and the possibility of copolymerization.
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Affiliation(s)
- Michael Weger
- Catalysis Research Center & WACKER-Chair of Macromolecular Chemistry, Technical University of Munich, Lichtenbergstrasse 4, 85748, Garching, Germany
| | - Raphael K Grötsch
- Catalysis Research Center & WACKER-Chair of Macromolecular Chemistry, Technical University of Munich, Lichtenbergstrasse 4, 85748, Garching, Germany
| | - Maximilian G Knaus
- Catalysis Research Center & WACKER-Chair of Macromolecular Chemistry, Technical University of Munich, Lichtenbergstrasse 4, 85748, Garching, Germany
| | - Marco M Giuman
- Catalysis Research Center & WACKER-Chair of Macromolecular Chemistry, Technical University of Munich, Lichtenbergstrasse 4, 85748, Garching, Germany
| | - David C Mayer
- Catalysis Research Center & Chair of Inorganic and Metal-Organic Chemistry, Technical University of Munich, Lichtenbergstrasse 4, 85748, Garching, Germany
| | - Philipp J Altmann
- Catalysis Research Center & Chair of Inorganic and Metal-Organic Chemistry, Technical University of Munich, Lichtenbergstrasse 4, 85748, Garching, Germany
| | - Estelle Mossou
- Institute Laue-Langevin, 71 avenue des Martyrs CS 20156, 38042, Grenoble, France.,Faculty of Natural Sciences, Keele University, Staffordshire, ST5 5BG, UK
| | - Birger Dittrich
- Inorganic Chemistry und Structural Chemistry 2, Heinrich Heine Universität, Universitätsstrasse 1, 40225, Düsseldorf, Germany
| | - Alexander Pöthig
- Catalysis Research Center & Chair of Inorganic and Metal-Organic Chemistry, Technical University of Munich, Lichtenbergstrasse 4, 85748, Garching, Germany
| | - Bernhard Rieger
- Catalysis Research Center & WACKER-Chair of Macromolecular Chemistry, Technical University of Munich, Lichtenbergstrasse 4, 85748, Garching, Germany
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Fontaine FG, Rochette É. Ambiphilic Molecules: From Organometallic Curiosity to Metal-Free Catalysts. Acc Chem Res 2018; 51:454-464. [PMID: 29308653 DOI: 10.1021/acs.accounts.7b00514] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Ambiphilic molecules were first used as functional ligands for transition elements, which could enable intriguing organometallic transformations. In the past decade, these intramolecular Lewis pairs, first considered organometallic curiosities, have become staples in organometallic chemistry and catalysis, acting as Z ligands, activating inert molecules using the concept of frustrated Lewis pair (FLP) chemistry, and acting as metal-free catalysts. In this Account, we detail our contribution to this blossoming field of research, focusing on the use of ambiphilic molecules as metal-free catalysts for CO2 reduction and C-H borylation reactions. A major emphasis is put on the mechanistic investigations we carried out using reactivity studies and theoretical tools, which helped us steer our research from stoichiometric transformations to highly active catalytic processes. We first report the interaction of aluminum-phosphine ambiphilic molecules with carbon dioxide. Although these Lewis pairs can bind CO2, a study of the deactivation process in the presence of CO2 and hydroboranes led us to discover that simple phosphinoborane molecules could act as active precatalysts for the hydroboration of carbon dioxide into methanol precursors. In these systems, the Lewis basic sites interact with the reducing agents rather than with the electrophilic carbon of CO2, increasing the nucleophilicity of hydroboranes. Simultaneously, the weak Lewis acids stabilize the oxygen of the gas molecule in the transition state, leading to high reaction rates. Replacing the phosphine by an amine leads to a system enabling CO2 hydrogenation, albeit only in stoichiometric transformations. Investigation of the protodeborylation deactivation of aminoboranes led us to develop metal-free catalysts for the C-H borylation of heteroarenes. By protecting the Lewis acid sites of these catalysts using fluoride, we were able to synthesize practical, air-stable precatalysts allowing the convenient synthesis of heteroarylboronic esters on a multigram scale. Contrary to general perception of FLP chemistry, we also demonstrated that a significant increase in activity could be obtained by reducing the steric bulk around the active site. These smaller systems exist as stable dimers and are more energetically costly to dissociate into active FLPs, but the approach of the substrate and the C-H activation step are significantly favored compared to the bulkier analogues. An in-depth study of the stability and reactivity of these aminoborane molecules also allowed us to develop a metal-free catalytic S-H bond borylation system, and to report stoichiometric and spontaneous B-B bond formation and Csp3-H bond activation processes, highlighting the importance of H2 release as a thermodynamic driving force in these FLP transformations.
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Affiliation(s)
- Frédéric-Georges Fontaine
- Département de Chimie,
Centre de Catalyse et Chimie Verte, Université Laval, 1045 Avenue de
la Médecine, Québec, Québec, Canada, G1V 0A6
| | - Étienne Rochette
- Département de Chimie,
Centre de Catalyse et Chimie Verte, Université Laval, 1045 Avenue de
la Médecine, Québec, Québec, Canada, G1V 0A6
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7
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Sudhakar G, Mahesh SK, Vemulapalli SPB, Nanubolu JB. Nazarov Cyclization and Tandem [4 + 2]-Cycloaddition Reactions of Donor–Acceptor Cyclopropanes. Org Lett 2017; 19:4500-4503. [DOI: 10.1021/acs.orglett.7b02061] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gangarajula Sudhakar
- Department of CPC (Organic Chemistry-II), ‡Centre for NMR and
Structural Chemistry, §Centre for X-ray Crystallography, CSIR-Indian Institute of Chemical Technology, Hyderabad-500007, India
| | - S. K. Mahesh
- Department of CPC (Organic Chemistry-II), ‡Centre for NMR and
Structural Chemistry, §Centre for X-ray Crystallography, CSIR-Indian Institute of Chemical Technology, Hyderabad-500007, India
| | - S. Phani Babu Vemulapalli
- Department of CPC (Organic Chemistry-II), ‡Centre for NMR and
Structural Chemistry, §Centre for X-ray Crystallography, CSIR-Indian Institute of Chemical Technology, Hyderabad-500007, India
| | - Jagadeesh Babu Nanubolu
- Department of CPC (Organic Chemistry-II), ‡Centre for NMR and
Structural Chemistry, §Centre for X-ray Crystallography, CSIR-Indian Institute of Chemical Technology, Hyderabad-500007, India
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8
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Fontaine FG, Courtemanche MA, Légaré MA, Rochette É. Design principles in frustrated Lewis pair catalysis for the functionalization of carbon dioxide and heterocycles. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2016.05.005] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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9
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Sudhakar G, Raghavaiah J, Mahesh G, Singarapu KK. Nazarov cyclization of divinyl ketones bearing an ester group at the β-position: a remarkable effect of α-substitution and alkene geometry on regioselectivity. Org Biomol Chem 2016; 14:2866-72. [DOI: 10.1039/c6ob00081a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Nazarov cyclization of divinyl ketones with an ester at the β-position was examined with particular reference to where the cyclic double bond forms.
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Affiliation(s)
- Gangarajula Sudhakar
- CPC (Organic Chemistry-II) Division
- CSIR-Indian Institute of Chemical Technology
- Hyderabad-500007
- India
- Academy of Scientific and Innovative Research
| | - Jakka Raghavaiah
- CPC (Organic Chemistry-II) Division
- CSIR-Indian Institute of Chemical Technology
- Hyderabad-500007
- India
- Academy of Scientific and Innovative Research
| | - Gaddam Mahesh
- CPC (Organic Chemistry-II) Division
- CSIR-Indian Institute of Chemical Technology
- Hyderabad-500007
- India
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10
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Li Z, Boyd RJ, Burnell DJ. Computational Examination of (4 + 3) versus (3 + 2) Cycloaddition in the Interception of Nazarov Reactions of Allenyl Vinyl Ketones by Dienes. J Org Chem 2015; 80:12535-44. [PMID: 26595587 DOI: 10.1021/acs.joc.5b02397] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A computational examination of the tandem Nazarov/cycloaddition process involving an allenyl vinyl ketone with a diene has been carried out using the ωB97X-D/6-311++G(d,p)//ωB97X-D/6-31+G(d,p) method with solvation modeled by SMD-PCM. The barrier for the initial Lewis acid mediated Nazarov reaction, which provided the intermediate cyclic oxylallyl cation, was higher than that for any subsequent cycloaddition. The barrier for the first step of a subsequent stepwise reaction did not vary much with the diene, and the lowest barrier was with the diene in its s-trans conformation. Stepwise formation of a (4 + 3) cycloaddition product was not energetically feasible, but (3 + 2) cycloaddition products could have been produced through low energy pathways. The barrier for a concerted (4 + 3) cycloaddition did depend upon the diene, which was always in an s-cis geometry. The barriers for the compact and the extended geometries for the transition states of (4 + 3) cycloadditions were not much different.
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Affiliation(s)
- Zhe Li
- Department of Chemistry, Dalhousie University , P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada
| | - Russell J Boyd
- Department of Chemistry, Dalhousie University , P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada
| | - D Jean Burnell
- Department of Chemistry, Dalhousie University , P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada
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Devillard M, Nicolas E, Appelt C, Backs J, Mallet-Ladeira S, Bouhadir G, Slootweg JC, Uhl W, Bourissou D. Novel zwitterionic complexes arising from the coordination of an ambiphilic phosphorus-aluminum ligand to gold. Chem Commun (Camb) 2015; 50:14805-8. [PMID: 25319140 DOI: 10.1039/c4cc06992g] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Coordination of Mes2PC(=CHPh)AltBu2 to metal chlorides has been studied. Bridging P→M-Cl→Al coordinations were observed with Rh and Pd fragments, while chloride abstraction systematically occurred with gold. The resulting zwitterionic complexes have been fully characterized and analyzed by DFT calculations.
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Affiliation(s)
- Marc Devillard
- Université de Toulouse, UPS, LHFA, 118 route de Narbonne, 31062 Toulouse, France and CNRS, LHFA, UMR 5069, 31062 Toulouse, France.
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12
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Rochette É, Courtemanche MA, Pulis AP, Bi W, Fontaine FG. Ambiphilic Frustrated Lewis Pair Exhibiting High Robustness and Reversible Water Activation: Towards the Metal-Free Hydrogenation of Carbon Dioxide. Molecules 2015; 20:11902-14. [PMID: 26132911 PMCID: PMC6331835 DOI: 10.3390/molecules200711902] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 06/04/2015] [Accepted: 06/19/2015] [Indexed: 12/15/2022] Open
Abstract
The synthesis and structural characterization of a phenylene-bridged Frustrated Lewis Pair (FLP) having a 2,2,6,6-tetramethylpiperidine (TMP) as the Lewis base and a 9-borabicyclo[3.3.1]nonane (BBN) as the Lewis acid is reported. This FLP exhibits unique robustness towards the products of carbon dioxide hydrogenation. The compound shows reversible splitting of water, formic acid and methanol while no reaction is observed in the presence of excess formaldehyde. The molecule is incredibly robust, showing little sign of degradation after heating at 80 °C in benzene with 10 equiv. of formic acid for 24 h. The robustness of the system could be exploited in the design of metal-free catalysts for the hydrogenation of carbon dioxide.
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Affiliation(s)
- Étienne Rochette
- Department of Chemistry, Centre de Catalyse et Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec, QC G1V 0A6, Canada.
| | - Marc-André Courtemanche
- Department of Chemistry, Centre de Catalyse et Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec, QC G1V 0A6, Canada.
| | - Alexander P Pulis
- Department of Chemistry, University of Toronto, 80 George Street, Toronto, ON M5S 3H6, Canada.
| | - Wenhua Bi
- Department of Chemistry, Centre de Catalyse et Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec, QC G1V 0A6, Canada.
| | - Frédéric-Georges Fontaine
- Department of Chemistry, Centre de Catalyse et Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec, QC G1V 0A6, Canada.
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Morgan TDR, LeFort FM, Li Z, Marx VM, Boyd RJ, Burnell DJ. Interception of Nazarov Reactions of Allenyl Vinyl Ketones with Dienes: (3+2)- versus (4+3)-Cycloaddition and Subsequent Rearrangement. European J Org Chem 2015. [DOI: 10.1002/ejoc.201403618] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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14
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Morgan TDR, LeBlanc LM, Ardagh GH, Boyd RJ, Burnell DJ. Torquoselectivity in the Nazarov Reactions of Allenyl Vinyl Ketones. J Org Chem 2015; 80:1042-51. [DOI: 10.1021/jo502532a] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Timothy D. R. Morgan
- Department of Chemistry, Dalhousie University,
P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada
| | - Luc M. LeBlanc
- Department of Chemistry, Dalhousie University,
P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada
| | - Giselle H. Ardagh
- Department of Chemistry, Dalhousie University,
P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada
| | - Russell J. Boyd
- Department of Chemistry, Dalhousie University,
P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada
| | - D. Jean Burnell
- Department of Chemistry, Dalhousie University,
P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada
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Luo J, Zhou H, Hu J, Wang R, Tang Q. Efficient catalytic-free method to produce α-aryl cycloalkanones through highly chemoselective coupling of aryl compounds with oxyallyl cations. RSC Adv 2014. [DOI: 10.1039/c4ra01043d] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Efficient catalytic-free method to produce α-aryl cycloalkanones through highly chemoselective coupling of aryl compounds with oxyallyl cations at room temperature.
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Affiliation(s)
- Juan Luo
- Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology
- College of Pharmacy
- Chongqing Medical University
- Chongqing 400016, P. R. China
- The Faculty of Laboratory Medicine
| | - Hui Zhou
- Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology
- College of Pharmacy
- Chongqing Medical University
- Chongqing 400016, P. R. China
| | - Jiwei Hu
- Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology
- College of Pharmacy
- Chongqing Medical University
- Chongqing 400016, P. R. China
| | - Rui Wang
- School of Pharmacy & Bioengineering
- Chongqing University of Technology
- Chongqing 400054, P. R. China
| | - Qiang Tang
- Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology
- College of Pharmacy
- Chongqing Medical University
- Chongqing 400016, P. R. China
- The Faculty of Laboratory Medicine
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17
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Courtemanche MA, Larouche J, Légaré MA, Bi W, Maron L, Fontaine FG. A Tris(triphenylphosphine)aluminum Ambiphilic Precatalyst for the Reduction of Carbon Dioxide with Catecholborane. Organometallics 2013. [DOI: 10.1021/om400645s] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Marc-André Courtemanche
- Département de Chimie, Centre de Catalyse et
Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec (Québec),
Canada G1V 0A6
| | - Jérémie Larouche
- Département de Chimie, Centre de Catalyse et
Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec (Québec),
Canada G1V 0A6
| | - Marc-André Légaré
- Département de Chimie, Centre de Catalyse et
Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec (Québec),
Canada G1V 0A6
| | - Wenhua Bi
- Département de Chimie, Centre de Catalyse et
Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec (Québec),
Canada G1V 0A6
| | - Laurent Maron
- Université de Toulouse, INSA, UPS, LCPNO, CNRS, UMR 5215 CNRS-UPS-INSA,
135 avenue de Rangueil, Toulouse, France
| | - Frédéric-Georges Fontaine
- Département de Chimie, Centre de Catalyse et
Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec (Québec),
Canada G1V 0A6
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Kwon Y, McDonald R, West FG. Organoaluminum-Mediated Interrupted Nazarov Reaction. Angew Chem Int Ed Engl 2013; 52:8616-9. [DOI: 10.1002/anie.201303996] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 06/07/2013] [Indexed: 11/10/2022]
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Kwon Y, McDonald R, West FG. Organoaluminum-Mediated Interrupted Nazarov Reaction. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201303996] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Courtemanche MA, Légaré MA, Maron L, Fontaine FG. A highly active phosphine-borane organocatalyst for the reduction of CO2 to methanol using hydroboranes. J Am Chem Soc 2013; 135:9326-9. [PMID: 23750670 DOI: 10.1021/ja404585p] [Citation(s) in RCA: 251] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In this work, we report that organocatalyst 1-Bcat-2-PPh2-C6H4 ((1); cat = catechol) acts as an ambiphilic metal-free system for the reduction of carbon dioxide in presence of hydroboranes (HBR2 = HBcat (catecholborane), HBpin (pinacolborane), 9-BBN (9-borabicyclo[3.3.1]nonane), BH3·SMe2 and BH3·THF) to generate CH3OBR2 or (CH3OBO)3, products that can be readily hydrolyzed to methanol. The yields can be as high as 99% with exclusive formation of CH3OBR2 or (CH3OBO)3 with TON (turnover numbers) and TOF (turnover frequencies) reaching >2950 and 853 h(-1), respectively. Furthermore, the catalyst exhibits "living" behavior: once the first loading is consumed, it resumes its activity on adding another loading of reagents.
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Affiliation(s)
- Marc-André Courtemanche
- Département de Chimie, Centre de Catalyse et de Chimie Verte (C3V), Université Laval, Québec G1V 0A6, Canada
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