Asymmetric Cross-Coupling of Aldehydes with Diverse Carbonyl or Iminyl Compounds by Photoredox-Mediated Cobalt Catalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(15), С. 10857 - 10867

Опубликована: Апрель 8, 2024

The asymmetric cross-coupling of unsaturated bonds, hampered by their comparable polarity and reactivity, as well the scarcity efficient catalytic systems capable diastereo- enantiocontrol, presents a significant hurdle in organic synthesis. In this study, we introduce highly adaptable photochemical cobalt catalysis framework that facilitates chemo- stereoselective reductive cross-couplings between common aldehydes with broad array carbonyl iminyl compounds, including N-acylhydrazones, aryl ketones, aldehydes, α-keto esters. Our methodology hinges on synergistic mechanism driven photoredox-induced single-electron reduction subsequent radical–radical coupling, all precisely guided chiral catalyst. Various optically enriched β-amino alcohols unsymmetrical 1,2-diol derivatives (80 examples) have been synthesized good yields (up to 90% yield) high stereoselectivities >20:1 dr, 99% ee). Of particular note, approach accomplishes unattainable transformations disparate partners without reliance any external photosensitizer, thereby further emphasizing its versatility cost-efficiency.

Язык: Английский

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Recent Advances in Nonprecious Metal Catalysis

Organic Process Research & Development, Год журнала: 2023, Номер 27(3), С. 423 - 447

Опубликована: Фев. 17, 2023

Nonprecious-metal-catalyzed alternatives to powerful precious metal transformations are of increasing interest in academia and the pharmaceutical industry due lower cost, better sustainability, toxicity. With continual growth broad field nonprecious catalysis (NPMC), we have chosen highlight selected articles published from March June 2022 which intended examples NPMC that feel may be especially relevant development. We aim inspire academic industrial innovation through discussion herein.

Язык: Английский

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Visible-Light-Induced Defluorinative α-C(sp³)–H Alkylation for the Synthesis of gem-Difluoroallylated α-Trifluoromethylamines

Organic Letters, Год журнала: 2023, Номер 25(51), С. 9124 - 9129

Опубликована: Ноя. 17, 2023

Herein, we describe a novel and efficient photoredox catalytic Cα radical addition/defluoroalkylation coupling reaction between α-trifluoromethyl alkenes N-trifluoroethyl hydroxylamine. A series of gem-difluoroallylated α-trifluoromethylamines were synthesized by the addition enabled 1,2-H shift in situ-generated radical. Notably, this protocol is distinguished its mild conditions, easy operation, excellent functional group tolerability.

Язык: Английский

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The Application of Sulfonyl Hydrazides in Electrosynthesis: A Review of Recent Studies

ACS Omega, Год журнала: 2022, Номер 7(44), С. 39531 - 39561

Опубликована: Окт. 27, 2022

Sulfonyl hydrazides are viewed as alternatives to sulfinic acids and their salts or sulfonyl halides, which broadly used in organic synthesis work active pharmaceutical substances. Generally, considered good building blocks show powerful value a diverse range of reactions construct C–S bonds C–C bonds, even C–N sulfur, carbon, nitrogen sources, respectively. As profound synthetic tool, the electrosynthesis method was recently achieve efficient green applications hydrazides. Interestingly, many unique novel electrochemical syntheses using radical precursors have been developed, including cascade reactions, functionalization heterocycles, well continuous flow combining with since 2017. Accordingly, it is necessary specifically summarize recent developments only more deeply understand better design reactions. Herein, research 2017 reviewed detail based on chemical structures products reaction mechanisms.

Язык: Английский

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Nickel-Catalyzed Cross-Electrophile Ring Opening/gem-Difluoroallylation of Aziridines

Organic Letters, Год журнала: 2023, Номер 25(31), С. 5756 - 5761

Опубликована: Июль 28, 2023

Herein we report a nickel-catalyzed regioselective cross-electrophile ring opening reaction of sulfonyl-protected aziridines with trifluoromethyl-substituted alkenes as the gem-difluoroallylating agents, providing new and efficient entry to prepare gem-difluorobishomoallylic sulfonamides. Moreover, scaffold 6-fluoro-1,2,3,4-tetrahydropyridine can be constructed starting from products via NaH-mediated intramolecular defluorinative nucleophilic vinylic substitution.

Язык: Английский

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Catalytic defluorinative ketyl–olefin coupling by halogen-atom transfer

Chemical Science, Год журнала: 2022, Номер 13(26), С. 7855 - 7862

Опубликована: Янв. 1, 2022

Ketyl-olefin coupling reactions stand as one of the fundamental chemical transformations in synthetic chemistry and have been widely employed generation complex molecular architectures natural product synthesis. However, catalytic ketyl-olefin coupling, until recent development photoredox electrosynthesis through single-electron transfer mechanisms, has remained largely undeveloped. Herein, we describe a new approach to achieve by halogen-atom mechanism, which provides innovative efficient access various

Язык: Английский

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Nickel‐Catalyzed Unsymmetrical Bis‐Allylation of Alkynes

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(17)

Опубликована: Фев. 24, 2023

The catalytic bis-allylation of alkynes is an important but challenging protocol to construct all-carbon tetra-substituted alkenes. Particularly, the unsymmetrical remains as underexplored task date. We herein report unprecedented by simultaneously utilizing electrophilic trifluoromethyl alkene and nucleophilic allylboronate allylic reagents. With aid robust Ni0 /NHC catalysis, valuable skipped trienes can be obtained in high regio- stereo-selectivities under mild conditions. Mechanistic studies indicate that reaction may proceed through a β-fluorine elimination nickelacycle followed transmetalation step with allylboronate. present method exhibits good tolerance various functional groups. Besides, triene products undergo array elaborate transformations, which highlights potential applications this strategy.

Язык: Английский

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Iron-Catalyzed Reductive Ring Opening/gem-Difluoroallylation of Cyclopropyl Ketones

Organic Letters, Год журнала: 2023, Номер 25(11), С. 1883 - 1888

Опубликована: Март 13, 2023

By merging C-C and C-F bond cleavage, we developed a regioselective ring opening/gem-difluoroallylation of cyclopropyl ketones with α-trifluoromethylstyrenes, which proceeds under the catalysis iron combination manganese TMSCl as reducing agents, providing new entry to synthesis carbonyl-containing gem-difluoroalkenes. Remarkably, ketyl radical-induced selective cleavage following generation more-stable carbon-centered radicals enable complete regiocontrol this opening reaction for various substitution patterns cyclopropane ring.

Язык: Английский

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Cobalt‐Catalyzed Allylic Defluorinative Cross‐Electrophile Coupling between 1,1‐Difluoroalkyl Halides and α‐Trifluoromethyl Styrenes

Advanced Synthesis & Catalysis, Год журнала: 2023, Номер 365(8), С. 1165 - 1169

Опубликована: Март 24, 2023

Abstract In this protocol, we apply reductive cobalt catalysis in the allylic defluorinative cross‐electrophile coupling reaction between 1,1‐difluoroalkyl halides and α‐trifluoromethyl styrenes. This features broad substrate scope (39 examples), good tolerance of various functionalities, circumvention pregenerating organometallics, offering a general synthetic route to prepare diverse organofluorines incorporating both gem ‐difluoroalkene ‐difluoroalkane moiety. magnified image

Язык: Английский

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Nickel-Catalyzed Enantioselective Dearomative Heck-Reductive Allylic Defluorination Reaction of Indoles

Organic Letters, Год журнала: 2023, Номер 25(33), С. 6122 - 6127

Опубликована: Авг. 14, 2023

Herein, we describe a nickel-catalyzed asymmetric dearomative aryl-difluoroallylation reaction of indoles with α-trifluoromethyl alkenes as an electrophilic coupling partner. The proceeds via cascade sequence involving Heck cyclization and reductive allylic defluorination. A series gem-difluoroallyl substituted indolines are obtained in moderate to good yields (36-77% yield) excellent enantioselectivity (up 99% ee). features broad functional group tolerance, scaled-up synthesis, late-stage diversification.

Язык: Английский

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