Cross‐Coupling of α‐Carbonyl Sulfoxonium Ylides with C−H Bonds

Angewandte Chemie International Edition, Journal Year: 2017, Volume and Issue: 56(42), P. 13117 - 13121

Published: Aug. 29, 2017

Abstract The functionalization of carbon–hydrogen bonds in non‐nucleophilic substrates using α‐carbonyl sulfoxonium ylides has not been so far investigated, despite the potential safety advantages that such reagents would provide over either diazo compounds or their situ precursors. Described herein are cross‐coupling reactions with C(sp 2 )−H arenes and heteroarenes presence a rhodium catalyst. reaction proceeds by succession C−H activation, migratory insertion ylide into carbon–metal bond, protodemetalation, last step being turnover‐limiting. method is applied to synthesis benz[c]acridines when allied an iridium‐catalyzed dehydrative cyclization.

Language: Английский

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C–H bond functionalization based on metal carbene migratory insertion

Chemical Communications, Journal Year: 2015, Volume and Issue: 51(38), P. 7986 - 7995

Published: Jan. 1, 2015

C–H bond activation has been merged with carbene coupling to furnish a series of novel synthetic methodologies.

Language: Английский

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Recent advances in transition-metal-catalyzed carbene insertion to C–H bonds

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(7), P. 2759 - 2852

Published: Jan. 1, 2022

C-H functionalization has been emerging as a powerful method to establish carbon-carbon and carbon-heteroatom bonds. Many efforts have devoted transition-metal-catalyzed direct transformations of Metal carbenes generated in situ from transition-metal compounds diazo or its equivalents are usually applied the transient reactive intermediates furnish catalytic cycle for new C-C C-X bond formation. Using this strategy unactivated simple alkanes complex molecules can be further functionalized transformed multi-functionalized compounds. In area, carbene insertion bonds paid continuous attention. Diverse catalyst design strategies, synthetic methods, potential applications developed. This critical review will summarize advance dated up July 2021, by categories aliphatic C(sp3)-H, aryl (aromatic) C(sp2)-H, heteroaryl (heteroaromatic) C(sp2)-H bonds, alkenyl alkynyl C(sp)-H, well asymmetric more coverage given recent work. Due rapid development future directions topic also discussed. give authors an overview chemistry with focus on systems

Language: Английский

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Rhodium(III)-Catalyzed C–C Bond Formation of Quinoline N-Oxides at the C-8 Position under Mild Conditions

Organic Letters, Journal Year: 2014, Volume and Issue: 16(17), P. 4598 - 4601

Published: Aug. 20, 2014

The Rh(III)-catalyzed C-8 selective direct alkylation and alkynylation of quinoline N-oxides has been developed. reactions proceeded highly efficiently at room temperature over a broad range substrates with excellent regioselectivity functional group tolerance. This development demonstrates the synthetic utility N-oxide directing as stepping stone for remote C–H functionalization quinolines.

Language: Английский

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Rhodium(III)‐Catalyzed CC and CO Coupling of Quinoline N‐Oxides with Alkynes: Combination of CH Activation with O‐Atom Transfer

Angewandte Chemie International Edition, Journal Year: 2014, Volume and Issue: 53(40), P. 10794 - 10798

Published: Aug. 14, 2014

Abstract [Cp*Rh III ]‐catalyzed CH activation of arenes assisted by an oxidizing NO or NN directing group has allowed the construction a number hetercycles. In contrast, polar bond is well‐known to undergo O‐atom transfer (OAT) alkynes. Despite liability bonds in both and OAT, these two important areas evolved separately. this report, ] catalysts integrate efficient redox‐neutral coupling quinoline N ‐oxides with alkynes afford α‐(8‐quinolyl)acetophenones. process acts as for donor.

Language: Английский

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Transition-Metal-Catalyzed Cross-Coupling with Ketones or Aldehydes via N-Tosylhydrazones

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(24), P. 10592 - 10605

Published: May 22, 2020

Ketones and aldehydes play central roles in organic synthesis. There are numerous broadly used reactions that related to the carbonyl reactivity, such as Grignard reactions, Wittig aldol so on. In addition, formation of enol triflates is a classic protocol enables ketones be applied transition-metal-catalyzed cross-coupling which case considered precursors alkenyl electrophiles C-C bond-forming transformations. past decade, new type ketone- or aldehyde-based transformations has emerged. this first converted their corresponding N-tosylhydrazones, employed reaction partners various carbene-based reactions. The N-tosylhydrazone-based carbene couplings significantly enhance potential modern This Perspective aims give an overview coupling with N-tosylhydrazones from viewpoint exploring potentials

Language: Английский

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Regioselective Syntheses of 1,2‐Benzothiazines by Rhodium‐Catalyzed Annulation Reactions

Angewandte Chemie International Edition, Journal Year: 2015, Volume and Issue: 54(42), P. 12349 - 12352

Published: April 14, 2015

Abstract Rhodium‐catalyzed directed carbene insertions into aromatic CH bonds of S‐aryl sulfoximines lead to intermediates, which upon dehydration provide 1,2‐benzothiazines in excellent yields. The domino‐type process is regioselective and shows a high functional‐group tolerance. It scalable, the only by‐products are dinitrogen water. Three illustrative transformations underscore synthetic value products.

Language: Английский

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Rhodium(III)‐Catalyzed Transannulation of Cyclopropenes with N‐Phenoxyacetamides through CH Activation

Angewandte Chemie International Edition, Journal Year: 2014, Volume and Issue: 53(48), P. 13234 - 13238

Published: Sept. 29, 2014

Abstract An efficient rhodium(III)‐catalyzed synthesis of 2 H ‐chromene from N ‐phenoxyacetamides and cyclopropenes has been developed. The reaction represents the first example using as a three‐carbon unit in C(sp )H activations.

Language: Английский

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Sulfoxonium Ylides as a Carbene Precursor in Rh(III)-Catalyzed C–H Acylmethylation of Arenes

Organic Letters, Journal Year: 2017, Volume and Issue: 19(19), P. 5256 - 5259

Published: Sept. 13, 2017

Sulfoxonium ylides act as an efficient carbene precursor in rhodium(III)-catalyzed C-H acylmethlyation of a variety arenes assisted by different chelating groups, and both aryl- alkyl-substituted β-carbonyl sulfoxonium are applicable. The system proceeded under redox-neutral conditions with broad scope, high efficiency, functional group tolerance.

Language: Английский

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The Carbene Chemistry of N-Sulfonyl Hydrazones: The Past, Present, and Future

Chemical Reviews, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 10, 2025

N-Sulfonyl hydrazones have been extensively used as operationally safe carbene precursors in modern organic synthesis due to their ready availability, facile functionalization, and environmental benignity. Over the past two decades, there has tremendous progress chemistry of N-sulfonyl presence transition metal catalysts, under metal-free conditions, or using photocatalysts photoirradiation conditions. Many transfer reactions are unique cannot be achieved by any alternative methods. The discovery novel development highly enantioselective new skeletal editing represent notable recent achievements hydrazones. This review describes overall made hydrazones, organized based on reaction types, spotlighting current state-of-the-art remaining challenges addressed future. Special emphasis is devoted identifying, describing, comparing scope limitations methodologies, key mechanistic scenarios, potential applications complex molecules.

Language: Английский

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