1
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Chappell WP, Schur N, Vogel JA, Sammis GM, Melvin PR, Ball ND. Poison to Promise: The Resurgence of Organophosphorus Fluoride Chemistry. Chem 2024; 10:1644-1654. [PMID: 38947532 PMCID: PMC11212144 DOI: 10.1016/j.chempr.2024.04.008] [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] [Indexed: 07/02/2024]
Abstract
Organophosphorus(V) fluorides have a long and tumultuous history, with early applications as toxins and nerve agents reflecting their poisonous past. Behind these very real safety considerations, there is also growing potential in a wide range of fields, from chemical biology to drug development. The recent inclusion of organophosphorus(V) fluorides in click chemistry exemplifies the promise these compounds possess and brings these molecules to the brink of a resurgence. In this Perspective, we delve into the history of P(V)-F compounds, discuss the precautions needed to work with them safely, and explore recent advancements in their synthesis and application. We conclude by discussing how this field can continue on a path toward innovation.
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Affiliation(s)
- William P. Chappell
- Department of Chemistry, University of British Columbia,
2036 Main Mall, Vancouver, British Columbia, V6T 1Z1, Canada
| | - Natalie Schur
- Department of Chemistry, Pomona College, 645 North College
Avenue, Claremont, California 91711, United States of America
| | - James A. Vogel
- Department of Chemistry, Bryn Mawr College, Bryn Mawr,
Pennsylvania 19010, United States of America
| | - Glenn M. Sammis
- Department of Chemistry, University of British Columbia,
2036 Main Mall, Vancouver, British Columbia, V6T 1Z1, Canada
| | - Patrick R. Melvin
- Department of Chemistry, Bryn Mawr College, Bryn Mawr,
Pennsylvania 19010, United States of America
| | - Nicholas D. Ball
- Department of Chemistry, Pomona College, 645 North College
Avenue, Claremont, California 91711, United States of America
- Lead contact
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2
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Pietraru MH, Ponsard L, Lentz N, Thuéry P, Nicolas E, Cantat T. Fluorophosphoniums as Lewis acids in organometallic catalysis: application to the carbonylation of β-lactones. Chem Commun (Camb) 2024; 60:1043-1046. [PMID: 38174921 DOI: 10.1039/d3cc04282k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
We describe the synthesis and characterisation of four organic Lewis acids based on fluorophosphoniums, with tetracarbonyl cobaltate as the counter-anion: [R3PF]+[Co(CO)4]- (with R = o-Tol, Cy, iPr, and tBu). Their catalytic activity was investigated for the carbonylation of β-lactones to succinic anhydrides. In the presence of [tBu3PF]+[Co(CO)4]- IV (3 mol%), 90% of succinic anhydride was afforded from β-propiolactone after 16 h at 80 °C, at a very mild pressure of 2 bar of carbon monoxide. Our study sets the first example of the use of a main-group cation as a Lewis acidic partner in the cobalt-catalyzed carbonylation of β-lactones.
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Affiliation(s)
| | - Louise Ponsard
- Université Paris-Saclay, CEA, CNRS, NIMBE, Gif-sur-Yvette 91191, France.
| | - Nicolas Lentz
- Université Paris-Saclay, CEA, CNRS, NIMBE, Gif-sur-Yvette 91191, France.
| | - Pierre Thuéry
- Université Paris-Saclay, CEA, CNRS, NIMBE, Gif-sur-Yvette 91191, France.
| | - Emmanuel Nicolas
- Université Paris-Saclay, CEA, CNRS, NIMBE, Gif-sur-Yvette 91191, France.
| | - Thibault Cantat
- Université Paris-Saclay, CEA, CNRS, NIMBE, Gif-sur-Yvette 91191, France.
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3
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Reuter MB, Javier-Jiménez DR, Bushey CE, Waterman R. Group I Alkoxides and Amylates as Highly Efficient Silicon-Nitrogen Heterodehydrocoupling Precatalysts for the Synthesis of Aminosilanes. Chemistry 2023; 29:e202302618. [PMID: 37728424 DOI: 10.1002/chem.202302618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/19/2023] [Accepted: 09/20/2023] [Indexed: 09/21/2023]
Abstract
Group I alkoxides are highly active precatalysts in the heterodehydrocoupling of silanes and amines to afford aminosilane products. The broadly soluble and commercially available KOt Amyl was utilized as the benchmark precatalyst for this transformation. Challenging substrates such as anilines were found to readily couple primary, secondary, and tertiary silanes in high conversions (>90 %) after only 2 h at 40 °C. Traditionally challenging silanes such as Ph3 SiH were also easily coupled to simple primary and secondary amines under mild conditions, with reactivity that rivals many rare earth and transition-metal catalysts for this transformation. Preliminary evidence suggests the formation of hypercoordinated intermediates, but radicals were detected under catalytic conditions, indicating a mechanism that is rare for Si-N bond formation.
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Affiliation(s)
- Matthew B Reuter
- Department of Chemistry, University of Vermont, 82 University Place, 05405, Burlington, VT, USA
| | - Diego R Javier-Jiménez
- Department of Chemistry, University of Vermont, 82 University Place, 05405, Burlington, VT, USA
| | - Claire E Bushey
- Department of Chemistry, University of Vermont, 82 University Place, 05405, Burlington, VT, USA
| | - Rory Waterman
- Department of Chemistry, University of Vermont, 82 University Place, 05405, Burlington, VT, USA
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4
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Reuter MB, Bushey CE, Javier-Jiménez DR, Waterman R. Commercially available organolithium compounds as effective, simple precatalysts for silicon-nitrogen heterodehydrocoupling. Dalton Trans 2023; 52:13497-13506. [PMID: 37605890 DOI: 10.1039/d3dt02564k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
A family of commercially available organolithium compounds were found to effectively catalyze the heterodehydrocoupling of silanes and amines under ambient conditions. Ubiquitous nBuLi (1) was utilized as the benchmark catalyst, where an array of primary, secondary, and tertiary arylsilanes were coupled to electron-donating amines, affording aminosilanes in high conversions with short reaction times. Preliminary mechanistic analysis is consistent with a nucleophilic-type system that involves the formation of a hypervalent silicon intermediate. This work underscores the accessibility of Si-N heterodehydrocoupling, with organolithium reagents emerging as some of the most straightforward and cost-effective precatalysts for this transformation.
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Affiliation(s)
- Matthew B Reuter
- University of Vermont, Department of Chemistry, Discovery Hall, Burlington, VT 05405, USA.
| | - Claire E Bushey
- University of Vermont, Department of Chemistry, Discovery Hall, Burlington, VT 05405, USA.
| | - Diego R Javier-Jiménez
- University of Vermont, Department of Chemistry, Discovery Hall, Burlington, VT 05405, USA.
| | - Rory Waterman
- University of Vermont, Department of Chemistry, Discovery Hall, Burlington, VT 05405, USA.
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5
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Miller LP, Vogel JA, Harel S, Krussman JM, Melvin PR. Rapid Generation of P(V)-F Bonds Through the Use of Sulfone Iminium Fluoride Reagents. Org Lett 2023; 25:1834-1838. [PMID: 36897224 PMCID: PMC10043933 DOI: 10.1021/acs.orglett.3c00274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
Phosphorus-fluorine bonds have become increasingly relevant in the pharmaceutical industry. To continue their exploration, more efficient synthetic methods are needed. Here, we report the application of sulfone iminium fluoride (SIF) reagents to the synthesis of P(V)-F bonds. The SIF reagents promote the deoxyfluorination of phosphinic acids in just 60 s with excellent yields and scope. The same P(V)-F products can also be synthesized from secondary phosphine oxides using an SIF reagent.
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Affiliation(s)
- Lucy P Miller
- Department of Chemistry, Bryn Mawr College, Bryn Mawr, Pennsylvania 19010, United States
| | - James A Vogel
- Department of Chemistry, Bryn Mawr College, Bryn Mawr, Pennsylvania 19010, United States
| | - Shiraz Harel
- Department of Chemistry, Bryn Mawr College, Bryn Mawr, Pennsylvania 19010, United States
| | - Jenna M Krussman
- Department of Chemistry, Bryn Mawr College, Bryn Mawr, Pennsylvania 19010, United States
| | - Patrick R Melvin
- Department of Chemistry, Bryn Mawr College, Bryn Mawr, Pennsylvania 19010, United States
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6
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Leland BE, Mondal J, Trovitch RJ. Sustainable preparation of aminosilane monomers, oligomers, and polymers through Si-N dehydrocoupling catalysis. Chem Commun (Camb) 2023; 59:3665-3684. [PMID: 36857645 DOI: 10.1039/d2cc07092h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
This article covers historical and recent efforts to catalyse the dehydrocoupling of amines and silanes, a direct method for Si-N bond formation that offers hydrogen as a byproduct. In some applications, this transformation can be used as a sustainable replacement for traditional aminosilane synthesis, which demands corrosive chlorosilanes while generating one equivalent of ammonium salt waste for each Si-N bond that is formed. These advantages have driven the development of Si-N dehydrocoupling catalysts that span the periodic table, affording mechanistic insight that has led to advances in efficiency and selectivity. Given the divergence in precursors being used, characterization methods being relied on, and applications being targeted, this article highlights the formation of monomeric aminosilanes separately from oligomeric and polymeric aminosilanes. A recent study that allowed for the manganese catalysed synthesis of perhydropolysilazane and commercial chemical vapor deposition precursors is featured, and key opportunities for advancing the field of Si-N dehydrocoupling catalysis are discussed.
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Affiliation(s)
- Brock E Leland
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, USA.
| | - Joydeb Mondal
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, USA.
| | - Ryan J Trovitch
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, USA.
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7
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Kuciński K, Stachowiak-Dłużyńska H, Hreczycho G. Catalytic silylation of O–nucleophiles via Si–H or Si–C bond cleavage: A route to silyl ethers, silanols and siloxanes. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214456] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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8
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Bonnin Q, Edlová T, Sosa Carrizo ED, Fleurat-Lessard P, Brandès S, Cattey H, Richard P, Le Gendre P, Normand AT. Coordinatively Unsaturated Amidotitanocene Cations with Inverted σ and π Bond Strengths: Controlled Release of Aminyl Radicals and Hydrogenation/Dehydrogenation Catalysis. Chemistry 2021; 27:18175-18187. [PMID: 34669988 DOI: 10.1002/chem.202103487] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Indexed: 11/05/2022]
Abstract
Cationic amidotitanocene complexes [Cp2 Ti(NPhAr)][B(C6 F5 )4 ] (Cp=η5 -C5 H5 ; Ar=phenyl (1 a), p-tolyl (1 b), p-anisyl (1 c)) were isolated. The bonding situation was studied by DFT (Density Functional Theory) using EDA-NOCV (Energy Decomposition Analysis with Natural Orbitals for Chemical Valence). The polar Ti-N bond in 1 a-c features an unusual inversion of σ and π bond strengths responsible for the balance between stability and reactivity in these coordinatively unsaturated species. In solution, 1 a-c undergo photolytic Ti-N cleavage to release Ti(III) species and aminyl radicals ⋅NPhAr. Reaction of 1 b with H3 BNHMe2 results in fast homolytic Ti-N cleavage to give [Cp2 Ti(H3 BNHMe2 )][B(C6 F5 )4 ] (3). 1 a-c are highly active precatalysts in olefin hydrogenation and silanes/amines cross-dehydrogenative coupling, whilst 3 efficiently catalyzes amine-borane dehydrogenation. The mechanism of olefin hydrogenation was studied by DFT and the cooperative H2 activation key step was disclosed using the Activation Strain Model (ASM).
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Affiliation(s)
- Quentin Bonnin
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 avenue Alain Savary, 21000, Dijon, France
| | - Tereza Edlová
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 avenue Alain Savary, 21000, Dijon, France
| | - E Daiann Sosa Carrizo
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 avenue Alain Savary, 21000, Dijon, France
| | - Paul Fleurat-Lessard
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 avenue Alain Savary, 21000, Dijon, France
| | - Stéphane Brandès
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 avenue Alain Savary, 21000, Dijon, France
| | - Hélène Cattey
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 avenue Alain Savary, 21000, Dijon, France
| | - Philippe Richard
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 avenue Alain Savary, 21000, Dijon, France
| | - Pierre Le Gendre
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 avenue Alain Savary, 21000, Dijon, France
| | - Adrien T Normand
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 avenue Alain Savary, 21000, Dijon, France
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9
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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: 91] [Impact Index Per Article: 30.3] [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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10
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Peng H, Li T, Tian D, Yang H, Xu G, Tang W. Metal-free reduction of unsaturated carbonyls, quinones, and pyridinium salts with tetrahydroxydiboron/water. Org Biomol Chem 2021; 19:4327-4337. [PMID: 33908552 DOI: 10.1039/d1ob00300c] [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
A series of unsaturated carbonyls, quinones, and pyridinium salts have been effectively reduced to the corresponding saturated carbonyls, dihydroxybenzenes, and hydropyridines in moderate to high yields with tetrahydroxydiboron/water as a mild, convenient, and metal-free reduction system. Deuterium-labeling experiments have revealed this protocol to be an exclusive transfer hydrogenation process from water.
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Affiliation(s)
- Henian Peng
- State Key Laboratory of Bio-Organic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling Ling Road, Shanghai 200032, China.
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11
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Czyz ML, Taylor MS, Horngren TH, Polyzos A. Reductive Activation and Hydrofunctionalization of Olefins by Multiphoton Tandem Photoredox Catalysis. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01000] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Milena L. Czyz
- School of Chemistry, The University of Melbourne, Parkville 3010, Victoria, Australia
| | - Mitchell S. Taylor
- School of Chemistry, The University of Melbourne, Parkville 3010, Victoria, Australia
| | - Tyra H. Horngren
- School of Chemistry, The University of Melbourne, Parkville 3010, Victoria, Australia
| | - Anastasios Polyzos
- School of Chemistry, The University of Melbourne, Parkville 3010, Victoria, Australia
- CSIRO Manufacturing, Research Way, Clayton 3168, Victoria, Australia
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12
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Sharma MK, Wölper C, Haberhauer G, Schulz S. Vielseitiges Gallaphosphen: Von einem Ga‐P‐Ga‐Heteroallylkation über CO
2
‐Speicherung hin zu C(sp
3
)‐H‐Bindungsaktivierung. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202014381] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Mahendra K. Sharma
- Institut für Anorganische Chemie und Center für Nanointegration Duisburg-Essen (CENIDE) Universität Duisburg-Essen Universitätsstraße 5–7 45141 Essen Deutschland
| | - Christoph Wölper
- Institut für Anorganische Chemie und Center für Nanointegration Duisburg-Essen (CENIDE) Universität Duisburg-Essen Universitätsstraße 5–7 45141 Essen Deutschland
| | - Gebhard Haberhauer
- Institut für Organische Chemie Universität Duisburg-Essen Universitätsstraße 5–7 45141 Essen Deutschland
| | - Stephan Schulz
- Institut für Anorganische Chemie und Center für Nanointegration Duisburg-Essen (CENIDE) Universität Duisburg-Essen Universitätsstraße 5–7 45141 Essen Deutschland
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13
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Sharma MK, Wölper C, Haberhauer G, Schulz S. Multi-Talented Gallaphosphene for Ga-P-Ga Heteroallyl Cation Generation, CO 2 Storage, and C(sp 3 )-H Bond Activation. Angew Chem Int Ed Engl 2021; 60:6784-6790. [PMID: 33368922 PMCID: PMC7986129 DOI: 10.1002/anie.202014381] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Indexed: 11/12/2022]
Abstract
Gallaphosphene L(Cl)GaPGaL (2; L=HC[C(Me)N(2,6-i-Pr2 C6 H3 )]2 ), which is synthesized by reaction of LGa(Cl)PCO (1) with LGa, reacts with [Na(OCP)(dioxane)2.5 ] to LGa(OCP)PGaL (3), whereas chloride abstraction with LiBArF 4 yields [LGaPGaL][BArF 4 ] (4; BArF 4 =B(C6 F5 )4 ). 4 represents a heteronuclear analog of the allyl cation according to quantum chemical calculations. Remarkably, 2 reversibly reacts with CO2 to yield L(Cl)Ga-P[μ-C(O)O]2 GaL (5), while reactions with acetophenone and acetone selectively give compounds 6 and 7 by C(sp3 )-H bond activation.
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Affiliation(s)
- Mahendra K. Sharma
- Institute of Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CENIDE)University of Duisburg-EssenUniversitätsstrasse 5–745141EssenGermany
| | - Christoph Wölper
- Institute of Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CENIDE)University of Duisburg-EssenUniversitätsstrasse 5–745141EssenGermany
| | - Gebhard Haberhauer
- Institute of Organic ChemistryUniversity of Duisburg-EssenUniversitätsstrasse 5–745141EssenGermany
| | - Stephan Schulz
- Institute of Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CENIDE)University of Duisburg-EssenUniversitätsstrasse 5–745141EssenGermany
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14
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Guo CX, Yogendra S, Gomila RM, Frontera A, Hennersdorf F, Steup J, Schwedtmann K, Weigand JJ. A convenient access to fluorophosphonium triflate salts by electrophilic fluorination and anion exchange. Inorg Chem Front 2021. [DOI: 10.1039/d1qi00322d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The in situ one-pot electrophilic fluorination of phosphanes with NFSI followed by anion exchange with MeOTf gives highly electrophilic fluorophosphonium triflates – highly efficient catalysts for the synthesis of N-sulfonylamidines from amides.
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Affiliation(s)
- Chun-Xiang Guo
- Faculty of Chemistry and Food Chemistry
- TU Dresden
- Chair of Inorganic Molecular Chemistry
- 01062 Dresden
- Germany
| | - Sivathmeehan Yogendra
- Faculty of Chemistry and Food Chemistry
- TU Dresden
- Chair of Inorganic Molecular Chemistry
- 01062 Dresden
- Germany
| | - Rosa M. Gomila
- Department of Chemistry
- Universitat de Illes Balears
- 07122 Palma de Mallorca
- Spain
| | - Antonio Frontera
- Department of Chemistry
- Universitat de Illes Balears
- 07122 Palma de Mallorca
- Spain
| | - Felix Hennersdorf
- Faculty of Chemistry and Food Chemistry
- TU Dresden
- Chair of Inorganic Molecular Chemistry
- 01062 Dresden
- Germany
| | - Johannes Steup
- Faculty of Chemistry and Food Chemistry
- TU Dresden
- Chair of Inorganic Molecular Chemistry
- 01062 Dresden
- Germany
| | - Kai Schwedtmann
- Faculty of Chemistry and Food Chemistry
- TU Dresden
- Chair of Inorganic Molecular Chemistry
- 01062 Dresden
- Germany
| | - Jan J. Weigand
- Faculty of Chemistry and Food Chemistry
- TU Dresden
- Chair of Inorganic Molecular Chemistry
- 01062 Dresden
- Germany
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15
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Bornemann D, Pitts CR, Wettstein L, Brüning F, Küng S, Guan L, Trapp N, Grützmacher H, Togni A. Desoxyfluorierung von Phosphanoxiden: Ein allgemeiner Weg zu fluorierten Organophosphor(V)‐Verbindungen und noch mehr. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202010943] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Dustin Bornemann
- Departement Chemie und Angewandte Biowissenschaften ETH Zürich Vladimir-Prelog-Weg 2 8093 Zürich Schweiz
| | - Cody Ross Pitts
- Departement Chemie und Angewandte Biowissenschaften ETH Zürich Vladimir-Prelog-Weg 2 8093 Zürich Schweiz
- The Scripps Research Institute 10550 N. Torrey Pines Rd. La Jolla CA USA
| | - Lionel Wettstein
- Departement Chemie und Angewandte Biowissenschaften ETH Zürich Vladimir-Prelog-Weg 2 8093 Zürich Schweiz
| | - Fabian Brüning
- Departement Chemie und Angewandte Biowissenschaften ETH Zürich Vladimir-Prelog-Weg 2 8093 Zürich Schweiz
| | - Sebastian Küng
- Departement Chemie und Angewandte Biowissenschaften ETH Zürich Vladimir-Prelog-Weg 2 8093 Zürich Schweiz
| | - Liangyu Guan
- Departement Chemie und Angewandte Biowissenschaften ETH Zürich Vladimir-Prelog-Weg 2 8093 Zürich Schweiz
- The Scripps Research Institute 10550 N. Torrey Pines Rd. La Jolla CA USA
| | - Nils Trapp
- Departement Chemie und Angewandte Biowissenschaften ETH Zürich Vladimir-Prelog-Weg 2 8093 Zürich Schweiz
| | - Hansjörg Grützmacher
- Departement Chemie und Angewandte Biowissenschaften ETH Zürich Vladimir-Prelog-Weg 2 8093 Zürich Schweiz
| | - Antonio Togni
- Departement Chemie und Angewandte Biowissenschaften ETH Zürich Vladimir-Prelog-Weg 2 8093 Zürich Schweiz
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16
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Bornemann D, Pitts CR, Wettstein L, Brüning F, Küng S, Guan L, Trapp N, Grützmacher H, Togni A. Deoxygenative Fluorination of Phosphine Oxides: A General Route to Fluorinated Organophosphorus(V) Compounds and Beyond. Angew Chem Int Ed Engl 2020; 59:22790-22795. [PMID: 32852879 DOI: 10.1002/anie.202010943] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Indexed: 01/23/2023]
Abstract
Fluorinated organophosphorus(V) compounds are a very versatile class of compounds, but the synthetic methods available to make them bear the disadvantages of 1) occasional handling of toxic or pyrophoric PIII starting materials and 2) a dependence on hazardous fluorinating reagents such as XeF2 . Herein, we present a simple solution and introduce a deoxygenative fluorination (DOF) approach that utilizes easy-to-handle phosphine oxides as starting materials and effectively replaces harsh fluorinating reagents by a combination of oxalyl chloride and potassium fluoride. The reaction has proven to be general, as R3 PF2 , R2 PF3 , and RPF4 compounds (as well as various cations and anions derived from these) are accessible in good yields and on up to a multi-gram scale. DFT calculations were used to bolster our observations. Notably, the discovery of this new method led to a convenient synthesis of 1) new difluorophosphonium ions, 2) hexafluorophosphate salts, and 3) fluorinated antimony- and arsenic- compounds.
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Affiliation(s)
- Dustin Bornemann
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - Cody Ross Pitts
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland.,The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA, USA
| | - Lionel Wettstein
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - Fabian Brüning
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - Sebastian Küng
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - Liangyu Guan
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland.,The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA, USA
| | - Nils Trapp
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - Hansjörg Grützmacher
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - Antonio Togni
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
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17
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Reuter MB, Hageman K, Waterman R. Silicon-Nitrogen Bond Formation via Heterodehydrocoupling and Catalytic N-Silylation. Chemistry 2020; 27:3251-3261. [PMID: 33283902 DOI: 10.1002/chem.202004555] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/02/2020] [Indexed: 01/08/2023]
Abstract
Silicon-nitrogen bond formation is an important subfield in main group chemistry, and catalysis is an attractive route for efficient, selective formation of these bonds. Indeed, heterodehydrocoupling and N-silylation offer facile methods for the synthesis of small molecules through the coupling of primary, secondary, and tertiary silanes with N-containing substrates such as amines, carbazoles, indoles, and pyrroles. However, the reactivity of these catalytic systems is far from uniform, and critical issues are often encountered with product selectivity, conversions, substrate scope, catalyst activation, and in some instances, competing side reactions. Herein, a catalogue of catalysts and their reactivity for Si-N heterodehydrocoupling and N-silylation are reported.
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Affiliation(s)
- Matthew B Reuter
- Department of Chemistry, University of Vermont, 82 University Place, 05405, Burlington, VT, USA
| | - Kate Hageman
- Department of Chemistry, University of Vermont, 82 University Place, 05405, Burlington, VT, USA
| | - Rory Waterman
- Department of Chemistry, University of Vermont, 82 University Place, 05405, Burlington, VT, USA
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18
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Biswas K, Ghosh S, Basu B. Ion-exchange Resins and Polypeptide Supported Catalysts: A Critical Review. CURRENT GREEN CHEMISTRY 2020. [DOI: 10.2174/2213346107666200204125435] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Heterogeneous catalysis represents one of the important areas in the field of organic synthesis.
Major developments have been emerged during last few decades and polymer-supported catalysts
have been employed successfully in various catalytic organic transformations. Ion-exchange resins
and polypeptides are two important examples of such heterogeneous polymer-supported catalysts
among others because of their easy accessibility, stability, recoverability and reusability. Cross-linked
ion-exchange resins and polypeptides are highly insoluble, which make them better choice in terms of
their easy separation from the reaction mixture and subsequent recyclability. The present review article
provides an overview of different types of ion exchange resins as polymer-supported catalysts such
as amberlite resin, polystyrene resin, polyionic gel-based systems, ion-exchange resins and prolineimmobilized
species, PEG-bound poly (amino acid), amino acid anchored with Merrifild resin, amphiphilic
block polypeptides etc. Their preparation, characterizations and catalytic applications in diverse
organic transformations have been presented with critical analysis on their stability, mechanistic
overview and suitability etc.
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Affiliation(s)
- Kinkar Biswas
- Department of Chemistry, Raiganj University, University Road, Raiganj 733134, India
| | - Sujit Ghosh
- Department of Chemistry, Raiganj Surendranath Mahavidyalaya, Raiganj 733134, India
| | - Basudeb Basu
- Department of Chemistry, Raiganj University, University Road, Raiganj 733134, India
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19
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Morris LJ, Hill MS, Mahon MF, Manners I, S McMenamy F, Whittell GR. Heavier Alkaline-Earth Catalyzed Dehydrocoupling of Silanes and Alcohols for the Synthesis of Metallo-Polysilylethers. Chemistry 2020; 26:2954-2966. [PMID: 31899846 DOI: 10.1002/chem.201905313] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Indexed: 11/07/2022]
Abstract
The dehydrocoupling of silanes and alcohols mediated by heavier alkaline-earth catalysts, [Ae{N(SiMe3 )2 }2 ⋅(THF)2 ] (I-III) and [Ae{CH(SiMe3 )2 }2 ⋅(THF)2 ], (IV-VI) (Ae=Ca, Sr, Ba) is described. Primary, secondary, and tertiary alcohols were coupled to phenylsilane or diphenylsilane, whereas tertiary silanes are less tolerant towards bulky substrates. Some control over reaction selectivity towards mono-, di-, or tri-substituted silylether products was achieved through alteration of reaction stoichiometry, conditions, and catalyst. The ferrocenyl silylether, FeCp(C5 H4 SiPh(OBn)2 ) (2), was prepared and fully characterized from the ferrocenylsilane, FeCp(C5 H4 SiPhH2 ) (1), and benzyl alcohol using barium catalysis. Stoichiometric experiments suggested a reaction manifold involving the formation of Ae-alkoxide and hydride species, and a series of dimeric Ae-alkoxides [(Ph3 CO)Ae(μ2 -OCPh3 )Ae(THF)] (3 a-c, Ae=Ca, Sr, Ba) were isolated and fully characterized. Mechanistic experiments suggested a complex reaction mechanism involving dimeric or polynuclear active species, whose kinetics are highly dependent on variables such as the identity and concentration of the precatalyst, silane, and alcohol. Turnover frequencies increase on descending Group 2 of the periodic table, with the barium precatalyst III displaying an apparent first-order dependence in both silane and alcohol, and an optimum catalyst loading of 3 mol % Ba, above which activity decreases. With precatalyst III in THF, ferrocene-containing poly- and oligosilylethers with ferrocene pendent to- (P1-P4) or as a constituent (P5, P6) of the main polymer chain were prepared from 1 or Fe(C5 H4 SiPhH2 )2 (4) with diols 1,4-(HOCH2 )2 -(C6 H4 ) and 1,4-(CH(CH3 )OH)2 -(C6 H4 ), respectively. The resultant materials were characterized by NMR spectroscopy, gel permeation chromatography (GPC) and DOSY NMR spectroscopy, with estimated molecular weights in excess of 20,000 Da for P1 and P4. The iron centers display reversible redox behavior and thermal analysis showed P1 and P5 to be promising precursors to magnetic ceramic materials.
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Affiliation(s)
- Louis J Morris
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.,School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Michael S Hill
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Mary F Mahon
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Ian Manners
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.,Department of Chemistry, University of Victoria, Victoria, BC V8P 5C2, Canada
| | - Fred S McMenamy
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - George R Whittell
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
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20
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Neog K, Gogoi P. Recent advances in the synthesis of organophosphorus compounds via Kobayashi's aryne precursor: a review. Org Biomol Chem 2020; 18:9549-9561. [DOI: 10.1039/d0ob01988g] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
This review systematically summarizes the progress in aryne chemistry for the synthesis of organophosphorus compounds via aryne insertion into the C–P, P–N, P–P, P–O, PP, PN and PS bonds.
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Affiliation(s)
- Kashmiri Neog
- Applied Organic Chemistry Group
- Chemical Science and Technology Division
- CSIR-North East Institute of Science and Technology
- Jorhat 785006
- India
| | - Pranjal Gogoi
- Applied Organic Chemistry Group
- Chemical Science and Technology Division
- CSIR-North East Institute of Science and Technology
- Jorhat 785006
- India
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21
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Palumbo F, Rohrbach S, Tuttle T, Murphy JA. N‐Silylation of Amines Mediated by Et
3
SiH/KO
t
Bu. Helv Chim Acta 2019. [DOI: 10.1002/hlca.201900235] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Fabrizio Palumbo
- Department of Pure and Applied ChemistryUniversity of Strathclyde 295 Cathedral Street UK-Glasgow G1 1XL United Kingdom E-mal
| | - Simon Rohrbach
- Department of Pure and Applied ChemistryUniversity of Strathclyde 295 Cathedral Street UK-Glasgow G1 1XL United Kingdom E-mal
| | - Tell Tuttle
- Department of Pure and Applied ChemistryUniversity of Strathclyde 295 Cathedral Street UK-Glasgow G1 1XL United Kingdom E-mal
| | - John A. Murphy
- Department of Pure and Applied ChemistryUniversity of Strathclyde 295 Cathedral Street UK-Glasgow G1 1XL United Kingdom E-mal
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22
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Brewster RC, Suitor JT, Bennett AW, Wallace S. Transition Metal‐Free Reduction of Activated Alkenes Using a Living Microorganism. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201903973] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Richard C. Brewster
- Institute for Quantitative Biology, Biochemistry and BiotechnologySchool of Biological SciencesUniversity of Edinburgh, King's Buildings Alexander Crum Brown Road Edinburgh EH9 3FF UK
| | - Jack T. Suitor
- Institute for Quantitative Biology, Biochemistry and BiotechnologySchool of Biological SciencesUniversity of Edinburgh, King's Buildings Alexander Crum Brown Road Edinburgh EH9 3FF UK
| | - Adam W. Bennett
- School of ChemistryUniversity of EdinburghJoseph Black Building David Brewster Road, King's Buildings Edinburgh EH9 3FJ UK
| | - Stephen Wallace
- Institute for Quantitative Biology, Biochemistry and BiotechnologySchool of Biological SciencesUniversity of Edinburgh, King's Buildings Alexander Crum Brown Road Edinburgh EH9 3FF UK
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23
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Brewster RC, Suitor JT, Bennett AW, Wallace S. Transition Metal-Free Reduction of Activated Alkenes Using a Living Microorganism. Angew Chem Int Ed Engl 2019; 58:12409-12414. [PMID: 31286626 DOI: 10.1002/anie.201903973] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 06/26/2019] [Indexed: 01/07/2023]
Abstract
Microorganisms can be programmed to perform chemical synthesis via metabolic engineering. However, despite an increasing interest in the use of de novo metabolic pathways and designer whole-cells for small molecule synthesis, the inherent synthetic capabilities of native microorganisms remain underexplored. Herein, we report the use of unmodified E. coli BL21(DE3) cells for the reduction of keto-acrylic compounds and apply this whole-cell biotransformation to the synthesis of aminolevulinic acid from a lignin-derived feedstock. The reduction reaction is rapid, chemo-, and enantioselective, occurs under mild conditions (37 °C, aqueous media), and requires no toxic transition metals or external reductants. This study demonstrates the remarkable promiscuity of central metabolism in bacterial cells and how these processes can be leveraged for synthetic chemistry without the need for genetic manipulation.
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Affiliation(s)
- Richard C Brewster
- Institute for Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, King's Buildings, Alexander Crum Brown Road, Edinburgh, EH9 3FF, UK
| | - Jack T Suitor
- Institute for Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, King's Buildings, Alexander Crum Brown Road, Edinburgh, EH9 3FF, UK
| | - Adam W Bennett
- School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, King's Buildings, Edinburgh, EH9 3FJ, UK
| | - Stephen Wallace
- Institute for Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, King's Buildings, Alexander Crum Brown Road, Edinburgh, EH9 3FF, UK
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24
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Olaru M, Schröder A, Albers L, Duvinage D, Mebs S, Beckmann J. Functionalized Fluorophosphonium Ions. Chemistry 2019; 25:9861-9865. [DOI: 10.1002/chem.201902221] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Indexed: 11/07/2022]
Affiliation(s)
- Marian Olaru
- Institut für Anorganische Chemie und KristallographieUniversität Bremen Leobener Straße 7 28359 Bremen Germany
| | - Artem Schröder
- Institut für Anorganische Chemie und KristallographieUniversität Bremen Leobener Straße 7 28359 Bremen Germany
| | - Lena Albers
- Institut für ChemieCarl von Ossietzky Universität Oldenburg Carl-von-Ossietzky Str. 9-11 26129 Oldenburg Germany
| | - Daniel Duvinage
- Institut für Anorganische Chemie und KristallographieUniversität Bremen Leobener Straße 7 28359 Bremen Germany
| | - Stefan Mebs
- Institut für ExperimentalphysikFreie Universität Berlin Arnimallee 14 14195 Berlin Germany
| | - Jens Beckmann
- Institut für Anorganische Chemie und KristallographieUniversität Bremen Leobener Straße 7 28359 Bremen Germany
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25
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Homo- and heterodehydrocoupling of phosphines mediated by alkali metal catalysts. Nat Commun 2019; 10:2786. [PMID: 31243267 PMCID: PMC6594957 DOI: 10.1038/s41467-019-09832-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Accepted: 03/21/2019] [Indexed: 12/24/2022] Open
Abstract
Catalytic chemistry that involves the activation and transformation of main group substrates is relatively undeveloped and current examples are generally mediated by expensive transition metal species. Herein, we describe the use of inexpensive and readily available tBuOK as a catalyst for P-P and P-E (E = O, S, or N) bond formation. Catalytic quantities of tBuOK in the presence of imine, azobenzene hydrogen acceptors, or a stoichiometric amount of tBuOK with hydrazobenzene, allow efficient homodehydrocoupling of phosphines under mild conditions (e.g. 25 °C and < 5 min). Further studies demonstrate that the hydrogen acceptors play an intimate mechanistic role. We also show that our tBuOK catalysed methodology is general for the heterodehydrocoupling of phosphines with alcohols, thiols and amines to generate a range of potentially useful products containing P-O, P-S, or P-N bonds.
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26
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Gilhula JC, Radosevich AT. Tetragonal phosphorus(v) cations as tunable and robust catalytic Lewis acids. Chem Sci 2019; 10:7177-7182. [PMID: 31588285 PMCID: PMC6685354 DOI: 10.1039/c9sc02463h] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 06/17/2019] [Indexed: 01/19/2023] Open
Abstract
The synthesis and catalytic reactivity of a class of water-tolerant cationic phosphorus-based Lewis acids is reported.
The synthesis and catalytic reactivity of a class of water-tolerant cationic phosphorus-based Lewis acids is reported. Corrole-based phosphorus(v) cations of the type [ArP(cor)][B(C6F5)4] (Ar = C6H5, 3,5-(CF3)2C6H3; cor = 5,10,15-(C6H5)3corrolato3–, 5,10,15-(C6F5)3corrolato3–) were synthesized and characterized by NMR and X-ray diffraction. The visible electronic absorption spectra of these cationic phosphacorroles depend strongly on the coordination environment at phosphorus, and their Lewis acidities are quantified by spectrophotometric titrations. DFT analyses establish that the character of the P-acceptor orbital comprises P–N antibonding interactions in the basal plane of the phosphacorrole. Consequently, the cationic phosphacorroles display unprecedented stability to water and alcohols while remaining highly active and robust Lewis acid catalysts for carbonyl hydrosilylation, Csp3–H bond functionalization, and carbohydrate deoxygenation reactions.
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Affiliation(s)
- James C Gilhula
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , MA 02139 , USA .
| | - Alexander T Radosevich
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , MA 02139 , USA .
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27
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Sharma MK, Blomeyer S, Neumann B, Stammler HG, Ghadwal RS. Crystalline Divinyldiarsenes and Cleavage of the As=As Bond. Chemistry 2019; 25:8249-8253. [PMID: 31017700 DOI: 10.1002/chem.201901857] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Indexed: 11/07/2022]
Abstract
The first divinyldiarsenes [{(NHC)C(Ph)}As]2 (NHC=IPr 3 a, SIPr 3 b; IPr=C{(NAr)CH}2 ; SIPr=C{(NAr)CH2 }2 ; Ar=2,6-iPr2 C6 H3 ) are reported. Compounds 3 a and 3 b were prepared by the reduction of corresponding chlorides {(NHC)C(Ph)}AsCl2 (NHC=IPr 2 a, SIPr 2 b) with Mg. Calculations revealed a small HOMO-LUMO energy gap of 3.86 (3 a) and 4.24 eV (3 b). Treatment of 3 a with (Me2 S)AuCl led to the cleavage of the As=As bond to restore 2 a, which is expected to proceed via the diarsane [{(IPr)C(Ph)}AsCl]2 (4). Remarkably, 4 as well as 2 a can be selectively accessed on treatment of 3 a with an appropriate amount of C2 Cl6 . Moreover, 3 a readily reacts with PhEEPh (E=Se or Te) at room temperature to give {(IPr)C(Ph)}As(EPh)2 (E=Se 5 a; Te 5 b), revealing the cleavage of As=As and E-E bonds and the formation of As-E bonds. Such highly selective stepwise oxidation (3 a→4→2 a) and bond metathesis (3 a→5 a,b) reactions are unprecedented in main-group chemistry.
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Affiliation(s)
- Mahendra K Sharma
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Sebastian Blomeyer
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Beate Neumann
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Hans-Georg Stammler
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Rajendra S Ghadwal
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, 33615, Bielefeld, Germany
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28
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Li N, Guan BT. A Dialkyl Calcium Carbene Adduct: Synthesis, Structure, and Catalytic Cross-Dehydrocoupling of Silanes with Amines. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201900168] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Nan Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry; Nankai University; Tianjin 300071 P.R. China
| | - Bing-Tao Guan
- State Key Laboratory and Institute of Elemento-Organic Chemistry; Nankai University; Tianjin 300071 P.R. China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin 300071 P.R. China
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29
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Bauer H, Thum K, Alonso M, Fischer C, Harder S. Alkene Transfer Hydrogenation with Alkaline‐Earth Metal Catalysts. Angew Chem Int Ed Engl 2019; 58:4248-4253. [DOI: 10.1002/anie.201813910] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/21/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Heiko Bauer
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Katharina Thum
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Mercedes Alonso
- Algemene ChemieVrije Universiteit Brussel Pleinlaan 2 1050 Elsene Belgium
| | - Christian Fischer
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Sjoerd Harder
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
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30
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Bauer H, Thum K, Alonso M, Fischer C, Harder S. Alkene Transfer Hydrogenation with Alkaline‐Earth Metal Catalysts. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201813910] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Heiko Bauer
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Katharina Thum
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Mercedes Alonso
- Algemene ChemieVrije Universiteit Brussel Pleinlaan 2 1050 Elsene Belgium
| | - Christian Fischer
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Sjoerd Harder
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
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31
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Abstract
This year marks the 350th anniversary of the discovery of phosphorus by the alchemist Hennig Brand. However, this element was not included in the p-block of the periodic table until more recently. 2019 also marks the 150th anniversary of the preliminary tabular arrangement of the elements into the periodic system by Mendeleev. Of the 63 elements known in 1869, almost one-third of them belonged to what ultimately became the p-block, and Mendeleev predicted the existence of both gallium and germanium as well. The elements of the p-block have a disparate and varied history. Their chemical structure, reactivity, and properties vary widely. Nevertheless, in recent years, a better understanding of trends in p-block reactivity, particularly the behavior of those elements not typically found in biological systems, has led to a promising array of emerging applications, highlighted herein.
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32
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Süsse L, LaFortune JHW, Stephan DW, Oestreich M. Axially Chiral, Electrophilic Fluorophosphonium Cations: Synthesis, Lewis Acidity, and Reactivity in the Hydrosilylation of Ketones. Organometallics 2019. [DOI: 10.1021/acs.organomet.8b00912] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lars Süsse
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
| | - James H. W. LaFortune
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 3H6
| | - Douglas W. Stephan
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 3H6
| | - Martin Oestreich
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
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33
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Du P, Zhao J. Comparative DFT study of metal-free Lewis acid-catalyzed C–H and N–H silylation of (hetero)arenes: mechanistic studies and expansion of catalyst and substrate scope. RSC Adv 2019; 9:37675-37685. [PMID: 35542279 PMCID: PMC9075773 DOI: 10.1039/c9ra07985h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 11/13/2019] [Indexed: 11/21/2022] Open
Abstract
Direct selective dehydrogenative silylation of thiophenes, pyridines, indoles and anilines to synthesize silyl-substituted aromatic compounds catalyzed by metal-free Lewis acids was achieved recently. However, there is still insufficient mechanistic data for these transformations. Using density functional theory calculations, we conducted a detailed investigation of the mechanism of the B(C6F5)3-catalyzed dehydrogenative silylation of N-methylindole, N,N-dimethylaniline and N-methylaniline. We successfully located the most favourable reaction pathways that can explain the experimental observations notably well. The most favourable pathway for B(C6F5)3-catalyzed C–H silylation of N-methylindole includes nucleophilic attack, proton abstraction and hydride migration. The C–H silylation of N,N-dimethylaniline follows a similar pathway to N-methylindole rather than that proposed by Hou's group. Our mechanism successfully explains that the transformations of N-methylindoline to N-methylindole produce different products at different temperatures. For N-methylaniline bearing both N–H and para-phenyl C–H bonds, the N–H silylation reaction is more facile than the C–H silylation reaction. Our proposed mechanism of N–H silylation of N-methylaniline is different from that proposed by the groups of Paradies and Stephan. Lewis acids Al(C6F5)3, Ga(C6F5)3 and B(2,6-Cl2C6H3)(p-HC6F4)2 can also catalyze the C–H silylation of N-methylindole like B(C6F5)3, but the most favourable pathways are those promoted by N-methylindoline. Furthermore, we also found several other types of substrates that would undergo C–H or N–H silylation reactions under moderate conditions. These findings may facilitate the design of new catalysts for the dehydrogenative silylation of inactivated (hetero)arenes. We investigated the mechanism of the dehydrosilylation of (hetero)arenes and extended the scope of the silylation catalysts and substrates.![]()
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Affiliation(s)
- Pan Du
- School of Life Science and Chemistry
- Jiangsu Second Normal University
- Nanjing 210013
- China
| | - Jiyang Zhao
- School of Environmental Science
- Nanjing Xiaozhuang University
- Nanjing 211171
- China
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34
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Neog K, Dutta D, Das B, Gogoi P. Aryne insertion into the PO bond: one-pot synthesis of quaternary phosphonium triflates. Org Biomol Chem 2019; 17:6450-6460. [DOI: 10.1039/c9ob01157a] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel transition-metal free synthetic strategy for the direct synthesis of quaternary phosphonium triflates via insertion of aryne into phosphine oxide.
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Affiliation(s)
- Kashmiri Neog
- Applied Organic Chemistry Group
- Chemical Science and Technology Division
- CSIR-North East Institute of Science and Technology
- Jorhat 785006
- India
| | - Dhiraj Dutta
- Applied Organic Chemistry Group
- Chemical Science and Technology Division
- CSIR-North East Institute of Science and Technology
- Jorhat 785006
- India
| | - Babulal Das
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Guwahati-781039
- India
| | - Pranjal Gogoi
- Applied Organic Chemistry Group
- Chemical Science and Technology Division
- CSIR-North East Institute of Science and Technology
- Jorhat 785006
- India
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35
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Andrews RJ, Chitnis SS, Stephan DW. Carbonyl and olefin hydrosilylation mediated by an air-stable phosphorus(iii) dication under mild conditions. Chem Commun (Camb) 2019; 55:5599-5602. [PMID: 31020971 DOI: 10.1039/c9cc02460c] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The readily-accessible, air-stable Lewis acid [(terpy)PPh][B(C6F5)4]21 is shown to mediate the hydrosilylation of aldehydes, ketones, and olefins. The utility and mechanism of these hydrosilylations are considered.
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Affiliation(s)
- Ryan J Andrews
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, ON M5S 3H6, Canada.
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36
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Stepen AJ, Bursch M, Grimme S, Stephan DW, Paradies J. Electrophilic Phosphonium Cation‐Mediated Phosphane Oxide Reduction Using Oxalyl Chloride and Hydrogen. Angew Chem Int Ed Engl 2018; 57:15253-15256. [DOI: 10.1002/anie.201809275] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Arne J. Stepen
- Department of ChemistryUniversity of Paderborn Warburger Strasse 100 33098 Paderborn Germany
- Department of ChemistryUniversity of Toronto 80 St. George St Toronto Ontario M5S3H6 Canada
| | - Markus Bursch
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstr. 4 53115 Bonn Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstr. 4 53115 Bonn Germany
| | - Douglas W. Stephan
- Department of ChemistryUniversity of Toronto 80 St. George St Toronto Ontario M5S3H6 Canada
| | - Jan Paradies
- Department of ChemistryUniversity of Paderborn Warburger Strasse 100 33098 Paderborn Germany
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37
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Stepen AJ, Bursch M, Grimme S, Stephan DW, Paradies J. Reduktion von Phosphanoxiden mit Oxalylchlorid und Wasserstoff, vermittelt durch ein elektrophiles Phosphoniumkation. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201809275] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Arne J. Stepen
- Department ChemieUniversität Paderborn Warburger Straße 100 33098 Paderborn Deutschland
- Department of ChemistryUniversity of Toronto 80 St. George St Toronto Ontario M5S3H6 Kanada
| | - Markus Bursch
- Mulliken Center for Theoretical ChemistryUniversität Bonn Beringstraße 4 53115 Bonn Deutschland
| | - Stefan Grimme
- Mulliken Center for Theoretical ChemistryUniversität Bonn Beringstraße 4 53115 Bonn Deutschland
| | - Douglas W. Stephan
- Department of ChemistryUniversity of Toronto 80 St. George St Toronto Ontario M5S3H6 Kanada
| | - Jan Paradies
- Department ChemieUniversität Paderborn Warburger Straße 100 33098 Paderborn Deutschland
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38
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Affiliation(s)
- Jan Paradies
- Department of Chemistry; University of Paderborn; Warburger Strasse 100 33098 Paderborn Germany
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39
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Yang M, Tofan D, Chen CH, Jack KM, Gabbaï FP. Digging the Sigma-Hole of Organoantimony Lewis Acids by Oxidation. Angew Chem Int Ed Engl 2018; 57:13868-13872. [PMID: 30151881 DOI: 10.1002/anie.201808551] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Indexed: 12/14/2022]
Abstract
The development of group 15 Lewis acids is an area of active investigation that has led to numerous advances in anion sensing and catalysis. While phosphorus has drawn considerable attention, emerging research shows that organoantimony(III) reagents may also act as potent Lewis acids. Comparison of the properties of SbPh3 , Sb(C6 F5 )3 , and SbArF 3 with those of their tetrachlorocatecholate analogues SbPh3 Cat, Sb(C6 F5 )3 Cat, and SbArF 3 Cat (Cat=o-O2 C6 Cl4 , ArF =3,5-(CF3 )2 C6 H3 ) demonstrates that the Lewis acidity of electron deficient organoantimony(III) reagents can be readily enhanced by oxidation to the +V state-as verified by binding studies, organic reaction catalysis, and computational studies. The results are rationalized by explaining that oxidation of the antimony center leads to a lowering of the accepting σ* orbital and a deeper carving of the associated σ-hole.
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Affiliation(s)
- Mengxi Yang
- Department of Chemistry, Texas A&M University, College Station, TX, 77843, USA
| | - Daniel Tofan
- Department of Chemistry, Texas A&M University, College Station, TX, 77843, USA
| | - Chang-Hong Chen
- Department of Chemistry, Texas A&M University, College Station, TX, 77843, USA
| | - Kevin M Jack
- 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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40
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Yang M, Tofan D, Chen C, Jack KM, Gabbaï FP. Digging the Sigma‐Hole of Organoantimony Lewis Acids by Oxidation. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201808551] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Mengxi Yang
- Department of ChemistryTexas A&M University College Station TX 77843 USA
| | - Daniel Tofan
- Department of ChemistryTexas A&M University College Station TX 77843 USA
| | - Chang‐Hong Chen
- Department of ChemistryTexas A&M University College Station TX 77843 USA
| | - Kevin M. Jack
- Department of ChemistryTexas A&M University College Station TX 77843 USA
| | - François P. Gabbaï
- Department of ChemistryTexas A&M University College Station TX 77843 USA
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41
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Kostenko A, Dobrovetsky R. The Role of the Fluoro-Hydrido-Phosphorane Intermediate in Catalytic Hydrosilylation of Acetophenone: Computational Study. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800823] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Arseni Kostenko
- A School of Chemistry; Raymond and Beverly Sackler Faculty of Exact Sciences; Tel Aviv University; 69978 Tel Aviv Israel
| | - Roman Dobrovetsky
- A School of Chemistry; Raymond and Beverly Sackler Faculty of Exact Sciences; Tel Aviv University; 69978 Tel Aviv Israel
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42
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Khan I, Reed‐Berendt BG, Melen RL, Morrill LC. FLP-Catalyzed Transfer Hydrogenation of Silyl Enol Ethers. Angew Chem Int Ed Engl 2018; 57:12356-12359. [PMID: 30106498 PMCID: PMC6207922 DOI: 10.1002/anie.201808800] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Indexed: 01/08/2023]
Abstract
Herein we report the first catalytic transfer hydrogenation of silyl enol ethers. This metal free approach employs tris(pentafluorophenyl)borane and 2,2,6,6-tetramethylpiperidine (TMP) as a commercially available FLP catalyst system and naturally occurring γ-terpinene as a dihydrogen surrogate. A variety of silyl enol ethers undergo efficient hydrogenation, with the reduced products isolated in excellent yields (29 examples, 82 % average yield).
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Affiliation(s)
- Imtiaz Khan
- School of ChemistryCardiff UniversityMain BuildingPark PlaceCardiffCF10 3ATUK
| | | | - Rebecca L. Melen
- School of ChemistryCardiff UniversityMain BuildingPark PlaceCardiffCF10 3ATUK
| | - Louis C. Morrill
- School of ChemistryCardiff UniversityMain BuildingPark PlaceCardiffCF10 3ATUK
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43
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44
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Waked AE, Ostadsharif Memar R, Stephan DW. Nitrogen-Based Lewis Acids Derived from Phosphonium Diazo Cations. Angew Chem Int Ed Engl 2018; 57:11934-11938. [PMID: 29806886 DOI: 10.1002/anie.201804183] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 05/21/2018] [Indexed: 12/16/2022]
Abstract
Reaction of PPh3 and [(p-ClC6 H4 )N2 ][BF4 ] affords [(p-ClC6 H4 )N(PPh3 )N(PPh3 )][BF4 ] 1, while reaction with (Ph2 PCH2 )2 gave [(p-ClC6 H4 )(NPh2 PCH2 )2 )][BF4 ] 2. These species confirm the Lewis acidity of [(p-ClC6 H4 )N2 (PR3 )][BF4 ] cations at N. In contrast, use of bulky phosphines afford the species [ArN2 (PR3 )][BF4 ] (R=tBu 3, Mes 4). Compound 3 undergoes one electron reduction to give the stable radical [(p-ClC6 H4 )N2 (PtBu3 )]. 5. Combination of 3 and PtBu3 acts as an FLP to effect (SPh)2 cleavage, generating [PhSPtBu3 ]+ and the radical [ArN2 (PR3 )]. . Collectively, these data affirm the ability of the cations [ArN2 (PR3 )]+ to behave as one or two electron acceptors.
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Affiliation(s)
- Alexander E Waked
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario, M5S3H6, Canada
| | | | - Douglas W Stephan
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario, M5S3H6, Canada
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45
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Waked AE, Ostadsharif Memar R, Stephan DW. Nitrogen-Based Lewis Acids Derived from Phosphonium Diazo Cations. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201804183] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Alexander E. Waked
- Department of Chemistry; University of Toronto; 80 St. George St. Toronto Ontario M5S3H6 Canada
| | | | - Douglas W. Stephan
- Department of Chemistry; University of Toronto; 80 St. George St. Toronto Ontario M5S3H6 Canada
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46
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Synthesis of a molecularly defined single-active site heterogeneous catalyst for selective oxidation of N-heterocycles. Nat Commun 2018; 9:1465. [PMID: 29654230 PMCID: PMC5899140 DOI: 10.1038/s41467-018-03834-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 03/15/2018] [Indexed: 11/09/2022] Open
Abstract
Generally, a homogeneous catalyst exhibits good activity and defined active sites but it is difficult to recycle. Meanwhile, a heterogeneous catalyst can easily be reused but its active site is difficult to reveal. It is interesting to bridge the gap between homogeneous and heterogeneous catalysis via controllable construction of a heterogeneous catalyst containing defined active sites. Here, we report that a molecularly defined, single-active site heterogeneous catalyst has been designed and prepared via the oxidative polymerization of maleimide derivatives. These polymaleimide derivatives can be active catalysts for the selective oxidation of heterocyclic compounds to quinoline and indole via the recycling of -C=O and -C-OH groups, which was confirmed by tracing the reaction with GC-MS using maleimide as the catalyst and by FT-IR analysis with polymaleimide as the catalyst. These results might promote the development of heterogeneous catalysts with molecularly defined single active sites exhibiting a comparable activity to homogeneous catalysts.
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47
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Erickson KA, Cibuzar MP, Mucha NT, Waterman R. Catalytic N-Si coupling as a vehicle for silane dehydrocoupling via α-silylene elimination. Dalton Trans 2018; 47:2138-2142. [PMID: 29363696 DOI: 10.1039/c7dt04507g] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Exploration of (N3N)ZrNMe2 (1, N3N = N(CH2CH2NSiMe3)33-) as a catalyst for the cross-dehydrocoupling or heterodehydrocoupling of silanes and amines suggested silylene reactivity. Further studies of the catalysis and stoichiometric modeling reactions hint at α-silylene elimination as the pivotal mechanistic step, which expands the 3p elements known to engage in this catalysis and provides a new strategy for the catalytic generation of low-valent fragments.
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Affiliation(s)
- Karla A Erickson
- Department of Chemistry, University of Vermont, Burlington, VT 05405, USA.
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48
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Tsao FA, Waked AE, Cao L, Hofmann J, Liu L, Grimme S, Stephan DW. S(vi) Lewis acids: fluorosulfoxonium cations. Chem Commun (Camb) 2018; 52:12418-12421. [PMID: 27711343 DOI: 10.1039/c6cc06929k] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Avenues to S-based Lewis acids were developed via the oxidation of aryl-sulfoxides with XeF2, giving difluorodiarylsulfoxides which react via fluoride abstraction to afford Lewis acidic fluorosulfoxonium cations; this acidity is derived from the S-F σ* orbital and has been probed both experimentally and computationally.
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Affiliation(s)
- Fu An Tsao
- Department of Chemistry, University of Toronto, 80 St. George St, Toronto, Ontario, CanadaM5S 3H6.
| | - Alexander E Waked
- Department of Chemistry, University of Toronto, 80 St. George St, Toronto, Ontario, CanadaM5S 3H6.
| | - Levy Cao
- Department of Chemistry, University of Toronto, 80 St. George St, Toronto, Ontario, CanadaM5S 3H6.
| | - Jordan Hofmann
- Department of Chemistry, University of Toronto, 80 St. George St, Toronto, Ontario, CanadaM5S 3H6.
| | - Lei Liu
- Mulliken Center for Theoretical Chemistry, Institut fuer Physikalische und Theoretische Chemie, Universitaet Bonn, Beringstrasse 4, D-53115 Bonn, Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institut fuer Physikalische und Theoretische Chemie, Universitaet Bonn, Beringstrasse 4, D-53115 Bonn, Germany
| | - Douglas W Stephan
- Department of Chemistry, University of Toronto, 80 St. George St, Toronto, Ontario, CanadaM5S 3H6.
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49
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LaFortune JHW, Szkop KM, Farinha FE, Johnstone TC, Postle S, Stephan DW. Probing steric influences on electrophilic phosphonium cations: a comparison of [(3,5-(CF3)2C6H3)3PF]+ and [(C6F5)3PF]+. Dalton Trans 2018; 47:11411-11419. [DOI: 10.1039/c8dt02594k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The electrophilic phosphonium cation (EPC) salt [(3,5-(CF3)2C6H3)3PF][B(C6F5)4] (2) can display catalytic activity greater than its thermodynamic acidity would suggest. The role of steric factors is explored.
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Affiliation(s)
| | - Kevin M. Szkop
- Department of Chemistry
- University of Toronto
- Toronto
- Canada M5S 3H6
| | - Farah E. Farinha
- Department of Chemistry
- University of Toronto
- Toronto
- Canada M5S 3H6
| | | | - Shawn Postle
- Department of Chemistry
- University of Toronto
- Toronto
- Canada M5S 3H6
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50
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Fasano V, LaFortune JHW, Bayne JM, Ingleson MJ, Stephan DW. Air- and water-stable Lewis acids: synthesis and reactivity of P-trifluoromethyl electrophilic phosphonium cations. Chem Commun (Camb) 2018; 54:662-665. [DOI: 10.1039/c7cc09128a] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Electrophilic phosphonium cations (EPCs) containing a –CF3 group are stable to air, water, alcohol and strong Brønsted acid and function as Lewis acid catalysts without requiring anhydrous reaction conditions.
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Affiliation(s)
- V. Fasano
- School of Chemistry, University of Manchester
- UK
- Department of Chemistry, University of Toronto
- Canada
| | | | - J. M. Bayne
- Department of Chemistry, University of Toronto
- Canada
| | | | - D. W. Stephan
- Department of Chemistry, University of Toronto
- Canada
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