1
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Bormann N, Ward JS, Bergmann AK, Wenz P, Rissanen K, Gong Y, Hatz WB, Burbaum A, Mulks FF. Diiminium Nucleophile Adducts Are Stable and Convenient Strong Lewis Acids. Chemistry 2023; 29:e202302089. [PMID: 37427889 DOI: 10.1002/chem.202302089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 07/08/2023] [Accepted: 07/10/2023] [Indexed: 07/11/2023]
Abstract
Strong Lewis acids are essential tools for manifold chemical procedures, but their scalable deployment is limited by their costs and safety concerns. We report a scalable, convenient, and inexpensive synthesis of stable diiminium-based reagents with a Lewis acidic carbon centre. Coordination with pyridine donors stabilises these centres; the 2,2'-bipyridine adduct shows a chelation effect at carbon. Due to high fluoride, hydride, and oxide affinities, the diiminium pyridine adducts are promising soft and hard Lewis acids. They effectively produce acylpyridinium salts from carboxylates that can acylate amines to give amides and imides even from electronically intractable coupling partners.
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Affiliation(s)
- Niklas Bormann
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Jas S Ward
- Department of Chemistry, University of Jyvaskyla, P. O. Box. 35, Survontie 9 B, 40014, Jyväskylä, Finland
| | - Ann Kathrin Bergmann
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Paula Wenz
- Department of Chemistry, University of Jyvaskyla, P. O. Box. 35, Survontie 9 B, 40014, Jyväskylä, Finland
| | - Kari Rissanen
- Department of Chemistry, University of Jyvaskyla, P. O. Box. 35, Survontie 9 B, 40014, Jyväskylä, Finland
| | - Yiwei Gong
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Wolf-Benedikt Hatz
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Alexander Burbaum
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Florian F Mulks
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
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2
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Parsons LWT, Berben LA. Metallated dihydropyridinates: prospects in hydride transfer and (electro)catalysis. Chem Sci 2023; 14:8234-8248. [PMID: 37564402 PMCID: PMC10411630 DOI: 10.1039/d3sc02080k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 07/14/2023] [Indexed: 08/12/2023] Open
Abstract
Hydride transfer (HT) is a fundamental step in a wide range of reaction pathways, including those mediated by dihydropyridinates (DHP-s). Coordination of ions directly to the pyridine ring or functional groups stemming therefrom, provides a powerful approach for influencing the electronic structure and in turn HT chemistry. Much of the work in this area is inspired by the chemistry of bioinorganic systems including NADH. Coordination of metal ions to pyridines lowers the electron density in the pyridine ring and lowers the reduction potential: lower-energy reactions and enhanced selectivity are two outcomes from these modifications. Herein, we discuss approaches for the preparation of DHP-metal complexes and selected examples of their reactivity. We suggest further areas in which these metallated DHP-s could be developed and applied in synthesis and catalysis.
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Affiliation(s)
- Leo W T Parsons
- Department of Chemistry, University of California Davis CA 95616 USA
| | - Louise A Berben
- Department of Chemistry, University of California Davis CA 95616 USA
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3
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Wu Y, Zhao Z, Chen T, Tan J, Qu Z, Grimme S, Zhao Y, Stephan DW. The Varied Frustrated Lewis Pair Reactivity of the Germylene Phosphaketene (CH{(CMe)(2,6‐
i
Pr
2
C
6
H
3
N)}
2
)GePCO. Chemistry 2022; 28:e202200666. [PMID: 35262970 PMCID: PMC9314608 DOI: 10.1002/chem.202200666] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Indexed: 01/08/2023]
Abstract
The germylene species (CH{(CMe)(2,6‐iPr2C6H3N)}2)GePCO 1 is shown to react with the Lewis acids (E(C6F5)3 E=B, Al). Nonetheless, 1 participates in FLP chemistry with electron deficient alkynes or olefins, acting as an intramolecular FLP. In contrast, in the presence of B(C6F5)3 and an electron rich alkyne, 1 behaves as Ge‐based nucleophile to effect intermolecular FLP addition to the alkyne. This reactivity demonstrates that the reaction pathway is controlled by the nature of the electrophile and nucleophile generated in solution, as revealed by extensive DFT calculations.
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Affiliation(s)
- Yile Wu
- Institute of Drug Discovery Technology Ningbo University Ningbo 315211 Zhejiang P. R. China
- State Key Laboratory of Elemento-Organic Chemistry Nankai University 30071 Tianjin P. R. China
| | - Zhao Zhao
- Institute of Drug Discovery Technology Ningbo University Ningbo 315211 Zhejiang P. R. China
| | - Ting Chen
- Institute of Drug Discovery Technology Ningbo University Ningbo 315211 Zhejiang P. R. China
| | - Jingjie Tan
- Institute of Drug Discovery Technology Ningbo University Ningbo 315211 Zhejiang P. R. China
| | - Zheng‐Wang Qu
- Mulliken Center for Theoretical Chemistry University of Bonn Beringstr. 4 53115 Bonn Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry University of Bonn Beringstr. 4 53115 Bonn Germany
| | - Yufen Zhao
- Institute of Drug Discovery Technology Ningbo University Ningbo 315211 Zhejiang P. R. China
- Department of Chemistry Xiamen University Xiamen 361005 Fujian P. R. China
| | - Douglas W. Stephan
- Institute of Drug Discovery Technology Ningbo University Ningbo 315211 Zhejiang P. R. China
- Department of Chemistry University of Toronto 80 St. George St Toronto ON M5S3H6 Canada
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4
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Sarkar P, Das S, Pati SK. Recent Advances in Group 14 and 15 Lewis Acids for Frustrated Lewis Pair Chemistry. Chem Asian J 2022; 17:e202200148. [PMID: 35320614 DOI: 10.1002/asia.202200148] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/22/2022] [Indexed: 11/10/2022]
Abstract
Frustrated Lewis pairs (FLP) which rely on the cooperative action of Lewis acids and Lewis bases, played a prominent role in the advancement of main-group catalysis. While the early days of FLP chemistry witnessed the dominance of boranes, there is a growing body of reports on alternative Lewis acids derived from groups 14 and 15. This short review focuses on the discovery of such non-boron candidates reported since 2015.
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Affiliation(s)
- Pallavi Sarkar
- Jawaharlal Nehru Centre for Advanced Scientific Research, Theoretical Sciences Unit, INDIA
| | - Shubhajit Das
- Jawaharlal Nehru Centre for Advanced Scientific Research, New Chemstry Unit, INDIA
| | - Swapan K Pati
- JNCASR, Theoretical Sciences Unit and New Chemistry Unit, Jakkur Campus, 560064, Bangalore, INDIA
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5
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Stephan DW. Diverse Uses of the Reaction of Frustrated Lewis Pair (FLP) with Hydrogen. J Am Chem Soc 2021; 143:20002-20014. [PMID: 34786935 DOI: 10.1021/jacs.1c10845] [Citation(s) in RCA: 87] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The articulation of the notion of "frustrated Lewis pairs" (FLPs) emerged from the discovery that H2 can be reversibly activated by combinations of sterically encumbered main group Lewis acids and bases. This has prompted numerous studies focused on various perturbations of the Lewis acid/base combinations and the applications to organic reductions. This Perspective focuses on the new directions and developments that are emerging from this FLP chemistry involving hydrogen. Three areas are discussed including new applications and approaches to FLP reductions, the reductions of small molecules, and the advances in heterogeneous FLP systems. These foci serve to illustrate that despite having its roots in main group chemistry, this simple concept of FLPs is being applied across the discipline.
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Affiliation(s)
- Douglas W Stephan
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
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6
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Liu WC, Kim Y, Gabbaï FP. Conformational Switching through the One-Electron Reduction of an Acridinium-based, γ-Cationic Phosphine Gold Complex. Chemistry 2021; 27:6701-6705. [PMID: 33528859 DOI: 10.1002/chem.202100389] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Indexed: 11/07/2022]
Abstract
Our efforts in the chemistry of gold complexes featuring ambiphilic phosphine-carbenium L/Z-type ligand have led us to consider the reduction of the carbenium moiety as a means to modulate the gold-carbenium interaction present in these complexes. Here, it was shown that the one-electron reduction of [(o-Ph2 P(C6 H4 )Acr)AuCl]+ (Acr=9-N-methylacridinium) produces a neutral stable radical, the structure of which showed a marked increase in the Au-Acr distance. Related structural changes were observed for the phosphine oxide analogue [(o-Ph2 P(O)(C6 H4 )Acr]+ , the reduction of which interfered with the P=O→carbenium interaction. These structural effects, driven by a reduction-induced change in the electronic and electrostatic characteristics of the compounds, showed that the charge and accepting properties of the carbenium unit can be modulated. These results highlight the redox-noninnocence of carbenium Z-type ligand, a feature that can be exploited to induce specific conformational changes.
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Affiliation(s)
- Wei-Chun Liu
- Department of Chemistry, Texas A&M University, College Station, TX, 77843, USA
| | - Youngmin Kim
- Department of Chemistry, Texas A&M University, College Station, TX, 77843, USA
| | - François P Gabbaï
- Department of Chemistry, Texas A&M University, College Station, TX, 77843, USA
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7
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Shaikh AC, Veleta JM, Moutet J, Gianetti TL. Trioxatriangulenium (TOTA +) as a robust carbon-based Lewis acid in frustrated Lewis pair chemistry. Chem Sci 2021; 12:4841-4849. [PMID: 34168760 PMCID: PMC8179643 DOI: 10.1039/d0sc05893a] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 02/07/2021] [Indexed: 12/15/2022] Open
Abstract
We report the reactivity between the water stable Lewis acidic trioxatriangulenium ion (TOTA+) and a series of Lewis bases such as phosphines and N-heterocyclic carbene (NHC). The nature of the Lewis acid-base interaction was analyzed via variable temperature (VT) NMR spectroscopy, single-crystal X-ray diffraction, UV-visible spectroscopy, and DFT calculations. While small and strongly nucleophilic phosphines, such as PMe3, led to the formation of a Lewis acid-base adduct, frustrated Lewis pairs (FLPs) were observed for sterically hindered bases such as P( t Bu)3. The TOTA+-P( t Bu)3 FLP was characterized as an encounter complex, and found to promote the heterolytic cleavage of disulfide bonds, formaldehyde fixation, dehydrogenation of 1,4-cyclohexadiene, heterolytic cleavage of the C-Br bonds, and interception of Staudinger reaction intermediates. Moreover, TOTA+ and NHC were found to first undergo single-electron transfer (SET) to form [TOTA]·[NHC]˙+, which was confirmed via electron paramagnetic resonance (EPR) spectroscopy, and subsequently form a [TOTA-NHC]+ adduct or a mixture of products depending the reaction conditions used.
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Affiliation(s)
- Aslam C Shaikh
- University of Arizona, Department of Chemistry and Biochemistry Tucson AZ USA
| | - José M Veleta
- University of Arizona, Department of Chemistry and Biochemistry Tucson AZ USA
| | - Jules Moutet
- University of Arizona, Department of Chemistry and Biochemistry Tucson AZ USA
| | - Thomas L Gianetti
- University of Arizona, Department of Chemistry and Biochemistry Tucson AZ USA
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8
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Karimi M, Borthakur R, Dorsey CL, Chen CH, Lajeune S, Gabbaï FP. Bifunctional Carbenium Dications as Metal-Free Catalysts for the Reduction of Oxygen. J Am Chem Soc 2020; 142:13651-13656. [DOI: 10.1021/jacs.0c04841] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Mohammadjavad Karimi
- Texas A&M University, Department of Chemistry, College Station, Texas 77843, United States
| | - Rosmita Borthakur
- Texas A&M University, Department of Chemistry, College Station, Texas 77843, United States
| | - Christopher L. Dorsey
- Texas A&M University, Department of Chemistry, College Station, Texas 77843, United States
| | - Chang-Hong Chen
- Texas A&M University, Department of Chemistry, College Station, Texas 77843, United States
| | - Sébastien Lajeune
- Texas A&M University, Department of Chemistry, College Station, Texas 77843, United States
| | - François P. Gabbaï
- Texas A&M University, Department of Chemistry, College Station, Texas 77843, United States
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9
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Simon M, Radius M, Wagner HE, Breher F. Imidazolyl Alanes – Synthesis, Structures, and Reactivity Studies. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Martin Simon
- Institute of Inorganic Chemistry Division Molecular Chemistry Karlsruhe Institute of Technology (KIT) Engesserstr.15 76131 Karlsruhe Germany
| | - Michael Radius
- Institute of Inorganic Chemistry Division Molecular Chemistry Karlsruhe Institute of Technology (KIT) Engesserstr.15 76131 Karlsruhe Germany
| | - Hanna E. Wagner
- Institute of Inorganic Chemistry Division Molecular Chemistry Karlsruhe Institute of Technology (KIT) Engesserstr.15 76131 Karlsruhe Germany
| | - Frank Breher
- Institute of Inorganic Chemistry Division Molecular Chemistry Karlsruhe Institute of Technology (KIT) Engesserstr.15 76131 Karlsruhe Germany
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10
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Kinder TA, Pior R, Blomeyer S, Neumann B, Stammler H, Mitzel NW. A Neutral Germanium/Phosphorus Frustrated Lewis Pair and Its Contrasting Reactivity Compared to Its Silicon Analogue. Chemistry 2019; 25:5899-5903. [PMID: 30843630 DOI: 10.1002/chem.201901068] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Indexed: 11/06/2022]
Affiliation(s)
- Timo A. Kinder
- Lehrstuhl für Anorganische Chemie und Strukturchemie und Centrum für, Molekulare Materialien CM2Universität Bielefeld Universitätsstraße 25 33615 Bielefeld Germany
| | - René Pior
- Lehrstuhl für Anorganische Chemie und Strukturchemie und Centrum für, Molekulare Materialien CM2Universität Bielefeld Universitätsstraße 25 33615 Bielefeld Germany
| | - Sebastian Blomeyer
- Lehrstuhl für Anorganische Chemie und Strukturchemie und Centrum für, Molekulare Materialien CM2Universität Bielefeld Universitätsstraße 25 33615 Bielefeld Germany
| | - Beate Neumann
- Lehrstuhl für Anorganische Chemie und Strukturchemie und Centrum für, Molekulare Materialien CM2Universität Bielefeld Universitätsstraße 25 33615 Bielefeld Germany
| | - Hans‐Georg Stammler
- Lehrstuhl für Anorganische Chemie und Strukturchemie und Centrum für, Molekulare Materialien CM2Universität Bielefeld Universitätsstraße 25 33615 Bielefeld Germany
| | - Norbert W. Mitzel
- Lehrstuhl für Anorganische Chemie und Strukturchemie und Centrum für, Molekulare Materialien CM2Universität Bielefeld Universitätsstraße 25 33615 Bielefeld Germany
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11
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Ilic S, Alherz A, Musgrave CB, Glusac KD. Thermodynamic and kinetic hydricities of metal-free hydrides. Chem Soc Rev 2018; 47:2809-2836. [DOI: 10.1039/c7cs00171a] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Thermodynamic and kinetic hydricities provide useful guidelines for the design of hydride donors with desirable properties for catalytic chemical reductions.
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Affiliation(s)
- Stefan Ilic
- Department of Chemistry
- University of Illinois at Chicago
- Chicago
- USA
- Chemical Sciences and Engineering Division
| | - Abdulaziz Alherz
- Department of Chemical and Biological Engineering
- University of Colorado
- Boulder
- USA
| | - Charles B. Musgrave
- Department of Chemical and Biological Engineering
- University of Colorado
- Boulder
- USA
- Department of Chemistry and Biochemistry
| | - Ksenija D. Glusac
- Department of Chemistry
- University of Illinois at Chicago
- Chicago
- USA
- Chemical Sciences and Engineering Division
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12
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Jain R, Mashuta MS, Buchanan RM, Grapperhaus CA. Electrocatalytic Hydrogen Evolution and Hydrogen Oxidation with a Ni(PS)
2
Complex. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201700590] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Rahul Jain
- Department of Chemistry University of Louisville 2320 South Brook Street 40292 Louisville KY USA
| | - Mark S. Mashuta
- Department of Chemistry University of Louisville 2320 South Brook Street 40292 Louisville KY USA
| | - Robert M. Buchanan
- Department of Chemistry University of Louisville 2320 South Brook Street 40292 Louisville KY USA
| | - Craig A. Grapperhaus
- Department of Chemistry University of Louisville 2320 South Brook Street 40292 Louisville KY USA
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13
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Abstract
The revelation that combinations of Lewis acids and bases for which dative bonding is impeded can activate dihydrogen led to the concept of "frustrated Lewis pairs" (FLPs). Over the past decade, a range of FLP systems and substrate molecules have precipitated a paradigm change in main-group chemistry and metal-free catalysis. The FLP motif has also found application in a growing body of chemical problems in organic synthesis, transition metal and free radical chemistry, materials, enzymatic models, and surface chemistry. The current state of FLP chemistry is assessed herein, and the outlook for the future considered.
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Affiliation(s)
- Douglas W Stephan
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S3H6, Canada
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14
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Fasano V, Curless LD, Radcliffe JE, Ingleson MJ. Frustrated Lewis Pair Mediated 1,2-Hydrocarbation of Alkynes. Angew Chem Int Ed Engl 2017; 56:9202-9206. [PMID: 28608991 PMCID: PMC5577509 DOI: 10.1002/anie.201705100] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Indexed: 01/26/2023]
Abstract
Frustrated Lewis pair (FLP) chemistry enables a rare example of alkyne 1,2-hydrocarbation with N-methylacridinium salts as the carbon Lewis acid. This 1,2-hydrocarbation process does not proceed through a concerted mechanism as in alkyne syn-hydroboration, or through an intramolecular 1,3-hydride migration as operates in the only other reported alkyne 1,2-hydrocarbation reaction. Instead, in this study, alkyne 1,2-hydrocarbation proceeds by a novel mechanism involving alkyne dehydrocarbation with a carbon Lewis acid based FLP to form the new C-C bond. Subsequently, intermolecular hydride transfer occurs, with the Lewis acid component of the FLP acting as a hydride shuttle that enables alkyne 1,2-hydrocarbation.
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Affiliation(s)
- Valerio Fasano
- School of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
| | - Liam D. Curless
- School of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
| | - James E. Radcliffe
- School of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
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15
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Fasano V, Curless LD, Radcliffe JE, Ingleson MJ. Frustrated Lewis Pair Mediated 1,2-Hydrocarbation of Alkynes. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201705100] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Valerio Fasano
- School of Chemistry; University of Manchester; Oxford Road Manchester M13 9PL UK
| | - Liam D. Curless
- School of Chemistry; University of Manchester; Oxford Road Manchester M13 9PL UK
| | - James E. Radcliffe
- School of Chemistry; University of Manchester; Oxford Road Manchester M13 9PL UK
| | - Michael J. Ingleson
- School of Chemistry; University of Manchester; Oxford Road Manchester M13 9PL UK
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16
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Fasano V, Radcliffe JE, Curless LD, Ingleson MJ. N-Methyl-Benzothiazolium Salts as Carbon Lewis Acids for Si-H σ-Bond Activation and Catalytic (De)hydrosilylation. Chemistry 2017; 23:187-193. [PMID: 27780294 PMCID: PMC5396135 DOI: 10.1002/chem.201604613] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Indexed: 11/08/2022]
Abstract
N-Me-Benzothiazolium salts are introduced as a new family of Lewis acids able to activate Si-H σ bonds. These carbon-centred Lewis acids were demonstrated to have comparable Lewis acidity towards hydride as found for the triarylboranes widely used in Si-H σ-bond activation. However, they display low Lewis acidity towards hard Lewis bases such as Et3 PO and H2 O in contrast to triarylboranes. The N-Me-benzothiazolium salts are effective catalysts for a range of hydrosilylation and dehydrosilylation reactions. Judicious selection of the C2 aryl substituent in these cations enables tuning of the steric and electronic environment around the electrophilic centre to generate more active catalysts. Finally, related benzoxazolium and benzimidazolium salts were found also to be active for Si-H bond activation and as catalysts for the hydrosilylation of imines.
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Affiliation(s)
- Valerio Fasano
- School of ChemistryUniversity of ManchesterManchesterM13 9PLUK
| | | | - Liam D. Curless
- School of ChemistryUniversity of ManchesterManchesterM13 9PLUK
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17
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Wilkins LC, Melen RL. Enantioselective Main Group Catalysis: Modern Catalysts for Organic Transformations. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2016.07.011] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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18
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Schilter D, Camara JM, Huynh MT, Hammes-Schiffer S, Rauchfuss TB. Hydrogenase Enzymes and Their Synthetic Models: The Role of Metal Hydrides. Chem Rev 2016; 116:8693-749. [PMID: 27353631 PMCID: PMC5026416 DOI: 10.1021/acs.chemrev.6b00180] [Citation(s) in RCA: 395] [Impact Index Per Article: 49.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hydrogenase enzymes efficiently process H2 and protons at organometallic FeFe, NiFe, or Fe active sites. Synthetic modeling of the many H2ase states has provided insight into H2ase structure and mechanism, as well as afforded catalysts for the H2 energy vector. Particularly important are hydride-bearing states, with synthetic hydride analogues now known for each hydrogenase class. These hydrides are typically prepared by protonation of low-valent cores. Examples of FeFe and NiFe hydrides derived from H2 have also been prepared. Such chemistry is more developed than mimicry of the redox-inactive monoFe enzyme, although functional models of the latter are now emerging. Advances in physical and theoretical characterization of H2ase enzymes and synthetic models have proven key to the study of hydrides in particular, and will guide modeling efforts toward more robust and active species optimized for practical applications.
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Affiliation(s)
- David Schilter
- Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea
- Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - James M. Camara
- Department of Chemistry, Yeshiva University, 500 West 185th Street, New York, New York 10033, United States
| | - Mioy T. Huynh
- Department of Chemistry, University of Illinois at Urbana–Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Sharon Hammes-Schiffer
- Department of Chemistry, University of Illinois at Urbana–Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Thomas B. Rauchfuss
- Department of Chemistry, University of Illinois at Urbana–Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
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19
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Abstract
The first 1 : 1 : 1 hetero-tri(aryl)borane cleaves H2 with various Lewis bases, and its electrochemistry is studied.
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20
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Lawson JR, Wilkins LC, André M, Richards EC, Ali MN, Platts JA, Melen RL. Synthesis and reactivity of N,N′-1,4-diazabutadiene derived borocations. Dalton Trans 2016; 45:16177-16181. [DOI: 10.1039/c6dt03360a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A new route to generate borocations has been established. By utilising readily synthesised diimines derived from commercially available materials, a new family of borenium- and boronium-cations can be synthesised from haloboranes.
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Affiliation(s)
| | | | - Manon André
- School of Chemistry
- Cardiff University
- Cardiff
- UK
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