Enantioselective Radical Reactions Using Chiral Catalysts

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(6), P. 5842 - 5976

Published: Jan. 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.

Language: Английский

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Catalytic Enantioselective Cyanation: Recent Advances and Perspectives

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(14), P. 7668 - 7690

Published: June 12, 2020

α-Chiral nitriles are prevalent structural motifs in natural products, drugs, and pharmaceutically active compounds. In addition, because the cyano group can undergo various diversifying reactions, they very versatile chiral building blocks for synthesis of optically aldehydes, ketones, carboxylic acids, carboxamides, amines, N-heterocycles such as tetrazolium. Accordingly, catalytic enantioselective cyanation reaction, one most important C–C bond forming has been intensely studied past three decades. While traditional efforts mainly focus on addition cyanide to highly polarized electrophiles well alkene hydrocyanation, intriguing directions cyanations have opened, including development cyanofunctionalization, via C–H functionalization, cleavage, invention bifunctional cyanating agents design asymmetric tandem exploit cyanide-free reactions. Additionally, significant advances also made developing unprecedented catalysts address a long-term challenge, structurally diverse Cα-tetrasubstituted or quaternary α-chiral nitriles. This perspective aims highlight these impressive advances, illustrates their key advantages future applications, provides some inspiration related research.

Language: Английский

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Copper-catalysed asymmetric radical cyanation

Nature Synthesis, Journal Year: 2022, Volume and Issue: 1(2), P. 107 - 116

Published: Jan. 31, 2022

Language: Английский

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On the Origin of Rh-Catalyzed Selective Ring-Opening Amidation of Substituted Cyclopropanols to Access β²-Amino Ketones

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(8), P. 3667 - 3675

Published: Feb. 15, 2022

β2-Amino carbonyls, an α-substituted β-amino scaffold, hold a prominent place in the development of new pharmaceuticals and peptidomimetics. Herein, we report highly efficient Rh-catalyzed ring-opening amidation substituted cyclopropanols, which turned out to serve as linchpin for selective synthesis β2-amino ketones outcompete formation β3-isomers. Instead generally accepted rationale consider steric factors β2-selectivity, orbital interaction was elucidated play more critical role amidative cyclopropanols generate key Rh–C intermediate. Subsequent inner-sphere acylnitrene transfer achieved excellent efficiency (TON > 5000) by using readily accessible dioxazolones amino source afford with broad applicability.

Language: Английский

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Enantioselective Remote Alkylation Enabled by Metallaphotoredox Catalysis via Selective C–C Bond Cleavage

ACS Catalysis, Journal Year: 2025, Volume and Issue: 15(3), P. 2212 - 2221

Published: Jan. 23, 2025

Despite recent advances in enantioselective radical coupling with strained cyclic rings, asymmetric reactions triggered by unstrained motifs remain rare. Herein, we report a mild and general strategy for activating diverse set of readily available alcohols the remote site-specific allylic alkylation ketones through combination photoredox-mediated proton-coupled electron transfer chiral chromium catalysis. This newly developed dual catalytic system exhibits extensive applicability, operates under conditions, offers straightforward operation, demonstrates tolerance to functional groups. The open-shell has also been applied late-stage modification complex drug natural product derivatives high levels enantioselectivity.

Language: Английский

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Metal-Catalyzed Transformations of Cyclopropanols via Homoenolates

Bulletin of the Chemical Society of Japan, Journal Year: 2020, Volume and Issue: 94(1), P. 265 - 280

Published: Sept. 28, 2020

Abstract Metal homoenolates represent uniquely useful organometallic intermediates in synthetic chemistry, allowing umpolung synthesis of β-functionalized carbonyl compounds. While siloxycyclopropanes had been established as reliable precursors to homoenolates, often stoichiometric, for diverse carbon–carbon bond forming reactions, unprotected cyclopropanols have emerged alternative and attractive catalytically generated, carbon–heteroatom bond-forming reactions. This review article provides an overview the development such homoenolate transformations, classified with respect metals involved cyclopropane ring opening.

Language: Английский

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Recent advances using cyclopropanols and cyclobutanols in ring-opening asymmetric synthesis

Green Synthesis and Catalysis, Journal Year: 2022, Volume and Issue: 3(3), P. 219 - 226

Published: May 23, 2022

Language: Английский

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Nickel-Catalyzed Carbonylation of Cyclopropanol with Benzyl Bromide for Multisubstituted Cyclopentenone Synthesis

Organic Letters, Journal Year: 2022, Volume and Issue: 24(14), P. 2699 - 2704

Published: April 7, 2022

Herein, we reported a Ni-catalyzed carbonylation of cyclopropanol with benzyl bromide to afford multisubstituted cyclopentenone under 1 atm CO. The reaction proceeds through cascade bromides, followed by generation nickel homoenolate from cyclopropanols via β-C elimination 1,4-diketones, which undergoes intramolecular Aldol condensation furnish highly substituted derivatives in moderate good yields. exhibits high functional group tolerance broad substrate scope.

Language: Английский

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

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(31), P. 4656 - 4659

Published: Jan. 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.

Language: Английский

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Copper-Catalyzed Asymmetric Cyanation of Alkenes via Carbonyl-Assisted Coupling of Alkyl-Substituted Carbon-Centered Radicals

Organic Letters, Journal Year: 2020, Volume and Issue: 22(16), P. 6299 - 6303

Published: July 31, 2020

Based on a copper-catalyzed radical relay strategy, the first asymmetric cyanation of alkyl-substituted alkenes has been developed. The reaction, featuring mild reaction conditions and excellent functional group compatibilities, provides an easy access to wide array structurally diverse enantioenriched alkyl nitriles in good yields. Notably, unstable carbon-centered generated by trifluoromethyl addition across terminal can be enantioselectively trapped chiral L*Cu(CN)2 with assistance carbonyl group.

Language: Английский

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