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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Heterogeneous Photocatalytic Organic Transformation Reactions Using Conjugated Polymers-Based Materials

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(20), P. 12256 - 12283

Published: Sept. 24, 2020

Photocatalytic heterogeneous organic transformation is considered as an efficient, clean atomic economy, and low-energy consumption strategy for synthesis. Conjugated polymers (CPs)-based materials have recently shown great potential diverse photocatalytic applications because of their unique properties, such structural designability, recyclability, high chemical stability, low cost, they emerged promising alternatives to traditional molecular or inorganic photocatalyst in photoredox reactions. Immense efforts been made toward the construction CPs-based versatile transformations. In this Review, we aim summarize recent progress photocatalysts transformations including oxidation, reduction, coupling, cycloaddition reaction. This Review discusses influence molecular, electronic, channel structure on light absorption, charge separation, mass transfer different The regulated synthesis, mechanistic discussions, future challenges systems are also considered. It expected that could not only deepen comprehension but open up inspirations feasibilities materials.

Language: Английский

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Stereoinduction in Metallaphotoredox Catalysis

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 60(4), P. 1714 - 1726

Published: July 17, 2020

Metallaphotoredox catalysis has evolved into an enabling platform to construct C(sp3 )-hybridized centers under remarkably mild reaction conditions. The cultivation of abundant radical precursor feedstocks significantly increased the scope transition-metal-catalyzed cross-couplings, especially with respect C(sp2 )-C(sp3 ) linkages. In recent years, considerable effort been devoted understanding origin stereoinduction in dual catalytic processes. this context, Ni- and Cu-catalyzed transformations have played a predominant role exploiting mode catalysis. Herein, we provide critical overview on progress enantioselective bond formations enabled by manifolds. Furthermore, selected stereochemical control elements within realm diastereoselective are discussed.

Language: Английский

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Enantioselective benzylic C–H arylation via photoredox and nickel dual catalysis

Nature Communications, Journal Year: 2019, Volume and Issue: 10(1)

Published: Aug. 7, 2019

Abstract The asymmetric cross-coupling reaction is developed as a straightforward strategy toward 1,1-diaryl alkanes, which are key skeleton in series of natural products and bioactive molecules recent years. Here we report an enantioselective benzylic C(sp 3 )−H bond arylation via photoredox/nickel dual catalysis. Sterically hindered chiral biimidazoline ligands designed for this reaction. Readily available alkyl benzenes aryl bromides with various functional groups tolerance can be easily directly transferred to useful alkanes including pharmaceutical intermediates molecules. This proceeds smoothly under mild conditions without the use external redox reagents.

Language: Английский

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4CzIPN-^tBu-Catalyzed Proton-Coupled Electron Transfer for Photosynthesis of Phosphorylated N-Heteroaromatics

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 143(2), P. 964 - 972

Published: Dec. 29, 2020

2,4,5,6-Tetrakis(3,6-di-tert-butyl-9H-carbazol-9-yl)isophthalonitrile (4CzIPN-tBu) was developed as a photocatalyst for the phosphorus-radical-initiated cascade cyclization reaction of isocyanides. By using 4CzIPN-tBu catalyst, we visible-light-induced proton-coupled electron transfer strategy generation phosphorus-centered radicals, via which wide range phosphorylated phenanthridines, quinolines, and benzothiazoles were successfully constructed.

Language: Английский

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Direct Enantioselective C(sp³)–H Acylation for the Synthesis of α-Amino Ketones

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(45), P. 19058 - 19064

Published: Oct. 30, 2020

A direct enantioselective acylation of α-amino C(sp3)-H bonds with carboxylic acids has been achieved via the merger transition metal and photoredox catalysis. This straightforward protocol enables cross-coupling a wide range acids, one class feedstock chemicals, readily available N-alkyl benzamides to produce highly valuable ketones in high enantioselectivities under mild conditions. The synthetic utility this method is further demonstrated by gram scale synthesis application late-stage functionalization. provides an unprecedented solution address challenging stereocontrol metallaphotoredox catalysis Mechanistic studies suggest α-C(sp3)-H bond benzamide coupling partner cleavage photocatalytically generated bromine radicals form alkyl radicals, which subsequently engages nickel-catalyzed asymmetric acylation.

Language: Английский

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Nickel/Photoredox‐Catalyzed Asymmetric Reductive Cross‐Coupling of Racemic α‐Chloro Esters with Aryl Iodides

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(13), P. 5172 - 5177

Published: Jan. 15, 2020

A unique nickel/organic photoredox co-catalyzed asymmetric reductive cross-coupling between α-chloro esters and aryl iodides is developed. This cross-electrophile coupling reaction employs an organic reductant (Hantzsch ester), whereas most reactions use stoichiometric metals. diverse array of valuable α-aryl formed under these conditions with high enantioselectivities (up to 94 %) good yields 88 %). α-Aryl represent important family nonsteroidal anti-inflammatory drugs. novel synergistic strategy expands the scope Ni-catalyzed reactions.

Language: Английский

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Recent advances in transition-metal-catalysed asymmetric coupling reactions with light intervention

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(22), P. 12808 - 12827

Published: Jan. 1, 2021

Transition metal-catalysed asymmetric coupling has been established as a robust tool for constructing complex organic molecules. Although this area extensively studied, the development of efficient protocols to construct stereogenic centres with excellent regio- and enantioselectivities is highly desirable remains challenging. Asymmetric transition metal catalysis light intervention provides practical alternative strategy current methods considerably expands synthetic utility result abundant feedstocks mild conditions. This tutorial review comprehensively summarizes recent advances in transition-metal-catalysed reactions intervention; particular, concise analysis substrate scope mechanistic scenarios governing stereocontrol discussed.

Language: Английский

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Enantioselective Radical Carbocyanation of 1,3-Dienes via Photocatalytic Generation of Allylcopper Complexes

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(11), P. 4168 - 4173

Published: March 11, 2021

1,3-Dienes are readily available feedstocks that widely used in the laboratory and industry. However, potential of converting 1,3-dienes into value-added products, especially chiral has not yet been fully exploited. By synergetic photoredox/copper catalysis, we achieve first visible-light-induced, enantioselective carbocyanation by using carboxylic acid derivatives trimethylsilyl cyanide. Under mild neutral conditions, a diverse range allyl cyanides produced generally good efficiency with high enantioselectivity from bench-stable user-safe chemicals. Moreover, preliminary results also confirm this success can be expanded to 1,3-enynes four-component carbonylative 1,3-enynes.

Language: Английский

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Construction of axial chirality via asymmetric radical trapping by cobalt under visible light

Nature Catalysis, Journal Year: 2022, Volume and Issue: 5(9), P. 788 - 797

Published: Sept. 15, 2022

Language: Английский

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