Electrochemically promoted N-heterocyclic carbene polymer-catalyzed cycloaddition of aldehyde with isocyanide acetate

Science China Chemistry, Journal Year: 2022, Volume and Issue: 65(10), P. 1873 - 1878

Published: Sept. 15, 2022

Language: Английский

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N-Heterocyclic Carbene-Catalyzed Remote Enantioselective C–C Bond Formation via 1,6-Addition with Formyl Enynes

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(3), P. 2127 - 2133

Published: Jan. 25, 2024

N-Heterocyclic carbenes (NHCs) have emerged as powerful organocatalysts in controlling the stereoselectivities of reaction sites that are remote from catalyst-binding position. Meanwhile, construction a stereogenic center at δ-position through NHC catalysis remains an unmet goal. Herein, we report NHC-catalyzed enantioselective 1,6-conjugated addition formyl enynes with nucleophiles oxidative LUMO activation strategy. The enables efficient chirality control enyne substrates, providing access to high-value-added enantio-enriched pyrano[2,3-b]indole and pyrano[2,3-c]pyrazole derivatives. In addition, central-to-axial transfer oxidation our products was realized, enabling facile axially chiral pyrans.

Language: Английский

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Photocatalytic Enantioselective Hydrosulfonylation of α,β‐Unsaturated Carbonyls with Sulfonyl Chlorides

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(46)

Published: Oct. 2, 2023

This research explores the enantioselective hydrosulfonylation of various α,β-unsaturated carbonyl compounds via use visible light and redox-active chiral Ni-catalysis, facilitating synthesis enantioenriched α-chiral sulfones with remarkable enantioselectivity (exceeding 99 % ee). A significant challenge entails enhancing reactivity between metal-coordinated moderate electrophilic sulfonyl radicals, aiming to minimize background reactions. The success our approach stems from two distinctive attributes: 1) Cl-atom abstraction employed for radical generation chlorides, 2) single-electron reduction produce a key enolate Ni-complex. latter process appears enhance feasibility radical's addition electron-rich radical. An in-depth investigation into reaction mechanism, supported by both experimental observations theoretical analysis, offers insight intricate process. Moreover, versatility methodology is highlighted through its successful application in late-stage functionalization complex bioactive molecules, demonstrating practicality as strategy producing sulfones.

Language: Английский

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Recent advances in catalytic asymmetric synthesis

Frontiers in Chemistry, Journal Year: 2024, Volume and Issue: 12

Published: May 9, 2024

Asymmetric catalysis stands at the forefront of modern chemistry, serving as a cornerstone for efficient creation enantiopure chiral molecules characterized by their high selectivity. In this review, we delve into realm asymmetric catalytic reactions, which spans various methodologies, each contributing to broader landscape enantioselective synthesis molecules. Transition metals play central role catalysts wide range transformations with ligands such phosphines, N -heterocyclic carbenes (NHCs), etc., facilitating formation C-C and C-X bonds, enabling precise control over stereochemistry. Enantioselective photocatalytic reactions leverage power light driving force electrocatalysis has emerged sustainable approach, being both atom-efficient environmentally friendly, while offering versatile toolkit reductions oxidations. Biocatalysis relies on nature’s most catalysts, i.e., enzymes, provide exquisite selectivity, well tolerance diverse functional groups under mild conditions. Thus, enzymatic optical resolution, kinetic resolution dynamic have revolutionized production compounds. organocatalysis uses metal-free organocatalysts, consisting modular phosphorus, sulfur nitrogen components, remarkably transformations. Additionally, unlocking traditionally unreactive C-H bonds through selective functionalization expanded arsenal synthesis, atom-economical construction Incorporating flow chemistry been transformative, continuous systems reaction conditions, enhancing efficiency optimization. Researchers are increasingly adopting hybrid approaches that combine multiple strategies synergistically tackle complex synthetic challenges. This convergence holds great promise, propelling field forward in form. As these methodologies evolve complement one another, they push boundaries what can be accomplished leading discovery novel, highly may lead groundbreaking applications across industries.

Language: Английский

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Enantioselective Synthesis of Allylic Sulfones via Rhodium-Catalyzed Direct Hydrosulfonylation of Allenes and Alkynes

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(25), P. 16996 - 17002

Published: June 14, 2024

A highly regio- and enantioselective hydrosulfonylation using commercially available sodium sulfinates is reported, providing the first direct asymmetric rhodium-catalyzed of allenes/alkynes to synthesize chiral allylic sulfones. Ligand screening studies demonstrated indispensable role C1-symmetric P,N-ligand (Rax,S,S)-StackPhim for achieving both high regioselecitivity (>20:1) enantioselectivity (up 97% ee). Notably, operationally simple method mild conditions allow rapid preparation sulfones with a wide scope functional groups. Moreover, use tert-butyldimethylsilyloxymethanesulfinate enables collective synthesis various sulfone derivatives after transformations protected hydroxymethyl product.

Language: Английский

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Exploring Molecular Complexity by N‐Heterocyclic Carbene Organocatalysis: New Activation and Reaction Diversity

The Chemical Record, Journal Year: 2022, Volume and Issue: 23(7)

Published: Nov. 7, 2022

Abstract The development of catalytic synthetic approaches towards molecular complexity from simple materials continues to be an ultimate goal in chemistry. Over the past decades, N‐heterocyclic carbene (NHC) organocatalysis has been extensively investigated provide opportunities for a vast number novel chemical transformations. Various activation modes and reactive intermediates enabled by NHC small‐molecule catalysts, such as Breslow intermediates, (homo)enolates, acyl azoliums their derived unsaturated exhibit great potential construction complicated skeletons. This personal account will summarize our group's recent work exploration new catalysis with focus on applications achieve diversity enantioselectivity preparation functional molecules.

Language: Английский

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Multicomponent Sulfonylation of Alkenes to Access β-Substituted Arylsulfones

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(6), P. 3772 - 3780

Published: March 6, 2023

A novel multicomponent sulfonylation of alkenes is described for the assembly various β-substituted arylsulfones using cheap and easily available K2S2O5 as a sulfur dioxide source. Of note, procedure does not need any extra oxidants metal catalysts exhibits relatively wide substrate scope good functional group compatibility. Mechanistically, an initial arylsulfonyl radical formed involving insertion with aryl diazonium salt, followed by alkoxyarylsulfonylation or hydroxysulfonylation alkenes.

Language: Английский

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Carbene-catalyzed chemoselective reaction of unsymmetric enedials for access to Furo[2,3-b]pyrroles

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: July 15, 2023

Abstract A carbene-catalyzed chemoselective reaction of unsymmetric enedials is disclosed. The provides a concise access to bicyclic furo[2,3-b]pyrroles derivatives in excellent selectivity. main challenge this the two aldehyde moieties enedial substrates. Mechanistic studies via experiments suggest that our chemoselectivity controls are mostly achieved on reducing properties different sited Breslow intermediates. Several side reactions processes and corresponding adducts also studied by high resolution mass spectroscopy analysis. Our method allows for efficient assembly furo[2,3-b]pyrrole structural their analogues widely found natural products pharmaceuticals.

Language: Английский

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Photocatalytic synthesis of alkyl–alkyl sulfonesviadirect C(sp³)–H bond functionalization

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(13), P. 2822 - 2827

Published: Jan. 1, 2023

We report a highly efficient one-pot, three-component strategy for the construction of alkyl-alkyl sulfones through photoinduced TBADT-catalyzed C(sp3)-H sulfonylation unactivated hydrocarbon compounds. A wide range commercially available compounds and bioactive molecules can be successfully applied to catalytic system, affording corresponding in good excellent yields (>50 examples, up 87% yield).

Language: Английский

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Catalyst-controlled stereoselective carbon–heteroatom bond formations by N-heterocyclic carbene (NHC) organocatalysis

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(17), P. 4437 - 4458

Published: Jan. 1, 2023

This review highlights recent advances in stereoselective carbon–heteroatom bond forming reactions, including C–N, C–O, C–S, C–F, C–P, etc ., that were enabled by NHC organocatalysis with a focus on new activation modes and reactive intermediates.

Language: Английский

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