Recent advances in copper-catalysed radical-involved asymmetric 1,2-difunctionalization of alkenes

Chemical Society Reviews, Год журнала: 2019, Номер 49(1), С. 32 - 48

Опубликована: Дек. 5, 2019

The radical-involved 1,2-difunctionalization of alkenes has developed into a robust tool for preparation complex organic molecules. Despite significant advances in this area, the catalytic asymmetric version still remains challenging task mainly due to difficulty stereocontrol highly reactive radical intermediates. Recently, owing good single-electron transfer ability and coordination with chiral ligands copper catalysts, remarkable achievements alkene difunctionalization have been made via synergistic combination ligands. This tutorial review highlights recent progress copper-catalysed mechanistic scenarios governing stereocontrol, an emphasis on utilization

Язык: Английский

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Copper(I)-Catalyzed Asymmetric Reactions Involving Radicals

Accounts of Chemical Research, Год журнала: 2019, Номер 53(1), С. 170 - 181

Опубликована: Окт. 28, 2019

ConspectusAsymmetric functionalization of alkyl radicals represents a robust yet underdeveloped method for efficient construction and decoration carbon skeletons in chiral organic molecules. In this field, we have been inspired by the excellent redox, radical trapping, Lewis acidic properties copper to develop several catalytic modes asymmetric reactions involving radicals. At beginning, discovered tandem hydrotrifluoromethylation unactivated alkenes enantioselective alkoxylation remote C(sp3)–H bonds copper/chiral phosphate relay catalysis. This success has stimulated us an three-component 1,2-dicarbofunctionalization 1,1-diarylalkenes using similar strategy via intermediates. Meanwhile, also secondary amine cooperative catalyst intramolecular cyclopropanation α-aldehyde methylene groups as C1 sources. The trapping intermediates CuII species during reaction was essential chemoselectivity toward cyclopropanation.Encouraged enantiocontrol with effective species, then sought single-electron-transfer Subsequently, successfully achieved series highly 1,2-aminofluoroalkylation, -aminoarylation, -diamination, -aminosilylation, -oxytrifluoromethylation alkenes. key high enantioinduction believed be CuII/chiral complexes. Besides, achiral pyridine ligand found indispensable achieving enantioselectivity, presumably stabilization CuIII 1,2-alkoxytrifluoromethylation reaction. discovery reminded tuning redox chemoreactivity centers ancillary ligand. As result, subsequently identified cinchona alkaloid-derived sulfonamides novel neutral-anionic hybrid ligands simultaneous chemo- enantiocontrol. We thus accomplished 1,2-iminoxytrifluoromethylation under catalysis copper/cinchona sulfonamide ligand, affording trifluoromethylated isoxazolines enantiomeric excess. Our copper-catalyzed provide expedient access diverse range valuable molecules broad application potential areas synthesis, medicine, agrochemical, material sciences.

Язык: Английский

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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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Nickel‐Catalyzed Asymmetric Reductive Diarylation of Vinylarenes

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(10), С. 3198 - 3202

Опубликована: Янв. 25, 2019

Abstract A nickel‐catalyzed asymmetric diarylation reaction of vinylarenes enables the preparation chiral α,α,β‐triarylated ethane scaffolds, which exist in a number biologically active molecules. The use reducing conditions with aryl bromides as coupling partners obviates need for stoichiometric organometallic reagents and tolerates broad range functional groups. application an N ‐oxyl radical ligand to nickel catalyst represents novel approach facilitate cross‐coupling reactions.

Язык: Английский

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Enantioselective Three-Component Fluoroalkylarylation of Unactivated Olefins through Nickel-Catalyzed Cross-Electrophile Coupling

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(21), С. 9604 - 9611

Опубликована: Май 11, 2020

A nickel-catalyzed, enantioselective, three-component fluoroalkylarylation of unactivated alkenes with aryl halides and perfluoroalkyl iodides has been described. This cross-electrophile coupling protocol utilizes a chiral nickel/BiOx system as well pendant chelating group to facilitate the challenging three-component, asymmetric difunctionalization alkenes, providing direct access valuable β-fluoroalkyl arylalkanes high efficiency excellent enantioselectivity. The mild conditions allow for broad substrate scope good functional toleration.

Язык: Английский

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Asymmetric Ni-Catalyzed Radical Relayed Reductive Coupling

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(31), С. 13515 - 13522

Опубликована: Июнь 29, 2020

Alkene dicarbofunctionalizations enable the streamlined construction of aliphatic structures and have thus been subject intense research efforts. Despite significant progress, catalytic asymmetric variants remain scarce. Inspired by advantages reductive cross-coupling approaches, we present here a highly efficient intermolecular Ni-catalyzed dicarbofunctionalization alkenes. Two distinct readily available electrophiles, namely, Csp2- Csp3-halides, are added simultaneously across variety olefins (vinyl amides, vinyl boranes, phosphonates) at room temperature in regio- enantioselective manner. The reaction, devoid sensitive organometallic reagents, takes advantage an situ generated chiral alkyl Ni(III)-intermediate to ensure stereodefined outcome Csp3–Csp2 bond-forming reaction. An (l)-(+)-isoleucine bisoxazoline ligand presence coordinating sites on alkene key for successful these "asymmetric radical relayed couplings" (ARRRCs). Further, multiple transformations amides obtained this process showcase potential new methodology straightforward assembly building blocks such as primary secondary amines oxazolines, highlighting its synthetic utility.

Язык: Английский

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Ni-Catalyzed Reductive Dicarbofunctionalization of Nonactivated Alkenes: Scope and Mechanistic Insights

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(35), С. 13812 - 13821

Опубликована: Авг. 21, 2019

Olefins devoid of directing or activating groups have been dicarbofunctionalized here with two electrophilic carbon sources under reductive conditions. Simultaneous formation one C(sp3)–C(sp3) and C(sp3)–C(sp2) bond across a variety unbiased π-systems proceeds exquisite selectivity by the combination Ni catalyst TDAE as sacrificial reductant. Control experiments computational studies revealed feasibility radical-based mechanism involving, formally, interconnected Ni(I)/Ni(III) processes demonstrated different ability Ni(I) species (Ni(I)I vs PhNi(I)) to reduce C(sp3)–I bond. The role reductant was also investigated in depth, suggesting that one-electron reduction Ni(II) is thermodynamically favored. Further, preferential activation alkyl aryl halides ArNi(I) complexes well high affinity ArNi(II) for secondary over tertiary C-centered radicals explains lack undesired homo- direct coupling products (Ar–Ar, Ar–Alk) these transformations.

Язык: Английский

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Nickel‐Catalyzed Asymmetric Reductive Arylalkylation of Unactivated Alkenes

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(20), С. 6722 - 6726

Опубликована: Март 20, 2019

Abstract Reported is an asymmetric reductive dicarbofunctionalization of unactivated alkenes. Under the catalysis a Ni/BOX system, various aryl bromides, incorporating pendant olefinic unit, were successfully reacted with array primary alkyl bromides in presence Zn as reductant, furnishing series benzene‐fused cyclic compounds bearing quaternary stereocenter high enantioselectivities. Notably, this reaction avoids use pregenerated organometallics and demonstrates tolerance sensitive functionalities. The preliminary mechanistic investigations reveal that Ni‐catalyzed proceeds cascade consisting migratory insertion cross‐coupling nickel(I)‐mediated intramolecular 5‐ exo cyclization enantiodetermining step.

Язык: Английский

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Dual Photoredox/Nickel‐Catalyzed Three‐Component Carbofunctionalization of Alkenes

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(35), С. 12286 - 12290

Опубликована: Июнь 26, 2019

Abstract The potential of merging photoredox and nickel catalysis to perform multicomponent alkene difunctionalizations under visible‐light irradiation is demonstrated here. Secondary tertiary alkyl groups, as well sulfonyl moieties can be added the terminal position double bond with simultaneous arylation internal carbon atom in a single step mild reaction conditions. process, devoid stoichiometric additives, benefits from use bench‐stable easy‐to‐handle reagents, operationally simple, tolerates wide variety functional groups.

Язык: Английский

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Atroposelective Phosphoric Acid Catalyzed Three‐Component Cascade Reaction: Enantioselective Synthesis of Axially Chiral N‐Arylindoles

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(44), С. 15824 - 15828

Опубликована: Авг. 28, 2019

An efficient organocatalytic atroposelective three-component cascade reaction of 2,3-diketoesters, aromatic amines, and 1,3-cyclohexanediones has been developed for the highly enantioselective synthesis axially chiral N-arylindoles. The success this method derives from use a newly second-generation spirocyclic phosphoric acid as catalyst. In addition, protocol was extended to an monophosphorus ligand.

Язык: Английский

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