Enantioselective Radical Reactions Using Chiral Catalysts

Chemical Reviews, Год журнала: 2022, Номер 122(6), С. 5842 - 5976

Опубликована: Янв. 24, 2022

Benefiting from the impressive increase in fundamental knowledge, last 20 years have shown a continuous burst of new ideas and consequently plethora catalytic methods for enantioselective radical reactions. This review aims to provide complete survey progress achieved over this latter period. The first part focuses on use chiral organocatalysts, these include catalysts covalently linked substrate those that interact with by weaker interactions like hydrogen bonds. second is devoted transition-metal redox catalysis which organized according increasing atomic number first-row transition metals (Ti, Cr, Fe, Mn, Co, Ni, Cu). Bioinspired manganese- iron-mediated hydroxylations oxidations are also discussed. A specific section dedicated reactivity Ru, Rh, Ir complexes as Lewis acids special focus at metal. Absorption photons result different events such energy transfer, single-electron hydrogen-atom transfer facilitating formation radicals. Organocatalysis has been successfully combined photocatalysts, opened pathways enlarging precursors available. merger photocatalysis organo- or metalla-photocatalysis brought novelty allowed discovery large original transformations. enzyme-catalyzed reactions involving intermediates largely benefit visible-light irradiation included review. provides comprehensive inventory goal detailing reaction mechanisms involved transformations any nonspecialist could find their own creativity invent yet unknown applications.

Язык: Английский

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Asymmetric three-component olefin dicarbofunctionalization enabled by photoredox and copper dual catalysis

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Март 22, 2021

Abstract The intermolecular three-component alkene vicinal dicarbofunctionalization (DCF) reaction allows installation of two different carbon fragments. Despite extensive investigation into its ionic chemistry, the enantioseletive radical-mediated versions DCF reactions remain largely unexplored. Herein, we report an intermolecular, enantioselective radical olefins enabled by merger addition and cross-coupling using photoredox copper dual catalysis. Key to success this protocol relies on chemoselective acyl cyanoalkyl radicals, generated in situ from redox-active oxime esters a photocatalytic N-centered iminyl radical-triggered C-C bond cleavage event, onto alkenes form new radicals. Single electron metalation such newly formed radicals TMSCN-derived L1 Cu(II)(CN) 2 complex leads asymmetric cross-coupling. This process proceeds under mild conditions, tolerates diverse range functionalities synthetic handles, leading valuable optically active β –cyano ketones alkyldinitriles, respectively, highly manner (>60 examples, up 97% ee).

Язык: Английский

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Photoelectrochemical Asymmetric Catalysis Enables Enantioselective Heteroarylcyanation of Alkenes via C–H Functionalization

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(34), С. 18753 - 18759

Опубликована: Авг. 15, 2023

The asymmetric difunctionalization of alkenes, a method transforming readily accessible alkenes into enantioenriched chiral structures high value, has long been focal point organic synthesis. Despite tremendous efforts in this domain, it remains considerable challenge to devise enantioselective oxidative dicarbofunctionalization even though these transformations can utilize stable and unfunctionalized functional group donors. In context, we report herein photoelectrocatalytic for the heteroarylcyanation aryl which employs heteroarenes through C-H functionalization. photoelectrochemical catalysis (PEAC) combines photoredox electrocatalysis facilitate formation two C-C bonds operating via hydrogen (H2) evolution obviating need external chemical oxidants.

Язык: Английский

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Copper-catalysed asymmetric radical cyanation

Nature Synthesis, Год журнала: 2022, Номер 1(2), С. 107 - 116

Опубликована: Янв. 31, 2022

Язык: Английский

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Copper-Catalyzed Asymmetric Functionalization of Vinyl Radicals for the Access to Vinylarene Atropisomers

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(24), С. 13476 - 13483

Опубликована: Июнь 10, 2023

A novel asymmetric radical strategy for the straightforward synthesis of atropisomerically chiral vinyl arenes has been established herein, proceeding through copper-catalyzed atroposelective cyanation/azidation aryl-substituted radicals. Critical to success relay process is capture highly reactive radicals with L*Cu(II) cyanide or azide species. Moreover, these axially vinylarene products can be easily transformed into enriched amides and amines, enantiomerically benzyl nitriles via an axis-to-center chirality transfer process, pure organocatalyst chemo-, diastereo-, enantioselective (4 + 2) cyclization reaction.

Язык: Английский

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Enantioselective Four-Component Arylsulfonylcyanation of Vinylarenes via the Insertion of SO₂ Enabled by SOgen as SO₂ Surrogate

ACS Catalysis, Год журнала: 2022, Номер 12(17), С. 10764 - 10770

Опубликована: Авг. 18, 2022

A copper-catalyzed four-component enantioselective arylsulfonylcyanation of vinylarenes has been developed that enables easy access to a variety chiral β-sulfonyl nitriles with up 95% yield and 96% ee. The reaction utilizes bench-stable SO2 surrogate (SOgen), takes place under mild conditions, exhibits good substrate scope functional group compatibility. Control experiments show the use SOgen as is key achieving excellent reactivities enantioselectivities. Preliminary mechanistic data indicates this vinylarene 1,2-difunctionalization likely proceeds by radical pathway. exemplifies rare case catalysis involving gaseous SO2.

Язык: Английский

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Enantioselective cyanation of propargylic C–H bonds via cooperative photoredox and copper catalysis

Chemical Communications, Год журнала: 2023, Номер 59(31), С. 4656 - 4659

Опубликована: Янв. 1, 2023

Herein, we report an enantioselective cyanation of propargylic C-H bonds by combining photoredox catalysis with a copper-catalyzed radical relay in which the was generated intramolecular 1,5-HAT process. This reaction provides easy access to optically pure propargyl nitrile compounds under mild conditions.

Язык: Английский

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Recent Advances in Theoretical Studies on Cu-Mediated Bond Formation Mechanisms Involving Radicals

ACS Catalysis, Год журнала: 2024, Номер 14(4), С. 2429 - 2454

Опубликована: Фев. 1, 2024

Copper-catalyzed radical transformations establish a powerful toolkit to construct versatile complex organic compounds. The copper-mediated bond formation step of radicals plays critical role in controlling chemo- and stereoselectivity copper-catalyzed transformation reactions. This involves three possible pathways: ion-type formation, substitution, reductive elimination. review highlights the recent advances theoretical studies on mechanisms models selectivity Cu-mediated radical-involved providing general mechanistic comprehension this key elementary copper catalysis.

Язык: Английский

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Arylcyanation of Styrenes by Photoactive Electron Donor–Acceptor Complexes/Copper Catalysis

Organic Letters, Год журнала: 2024, Номер 26(37), С. 7949 - 7955

Опубликована: Сен. 11, 2024

A novel electron donor-acceptor (EDA) complex/copper catalysis model has been proposed for the construction of 2,3-diarylpropionitriles under visible light conditions. The developed protocol proceeds via intermolecular charge transfer between photoactive EDA complex dibutamine (DBA), aryl thianthrenium salts, and trimethylsilyl cyanide (TMSCN), followed by a copper catalytic cycle. UV-vis absorption measurements confirm participation complexes as reactive intermediates. This three-component process smoothly in presence pharmaceutically relevant core structures sensitive functional groups, which offers possibility precise editing drug molecules with important scaffolds.

Язык: Английский

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Recent Developments in Copper(I)‐Catalyzed Enantioselective Alkynylation Reactions via a Radical Process

Chinese Journal of Chemistry, Год журнала: 2022, Номер 41(4), С. 481 - 489

Опубликована: Окт. 7, 2022

Comprehensive Summary Alkynes are one of the most significant functional groups in organic chemistry and great efforts have been made to explore efficient approach for construction chiral alkynes. The asymmetric C(sp 3 )–C(sp) cross‐coupling provides a complementary strategy through radical‐initiated process. However, stereocontrol highly reactive unstable radical intermediate has challenge decades. To address this problem, variety ligands developed initiating reaction achieving enantiocontrol alkyl radicals. This review summarizes recent developments copper‐catalyzed enantioselective alkynylation prochiral radicals their brief mechanistic studies.

Язык: Английский

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