Catalytic asymmetric reductive hydroalkylation of enamides and enecarbamates to chiral aliphatic amines

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: Feb. 26, 2021

Abstract To increase the reliability and success rate of drug discovery, efforts have been made to C( sp 3 ) fraction avoid flat molecules. -Rich enantiopure amines are most frequently encountered as chiral auxiliaries, synthetic intermediates for pharmaceutical agents bioactive natural products. Streamlined construction aliphatic has long regarded a paramount challenge. Mainstream approaches, including hydrogenation enamines imines, C–H amination, alkylation were applied synthesis with circumscribed skeleton structures; typically, carbon centre was adjacent an auxiliary aryl or ester group. Herein, we report mild general nickel-catalysed asymmetric reductive hydroalkylation effectively convert enamides enecarbamates into drug-like α-branched derivatives. This reaction involves regio- stereoselective hydrometallation enamide enecarbamate generate catalytic amount enantioenriched alkylnickel intermediate, followed by C–C bond formation via alkyl electrophiles.

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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Energy transfer photocatalysis: exciting modes of reactivity

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(3), P. 1068 - 1089

Published: Jan. 1, 2024

Leveraging light energy to expose the ‘dark’ reactive states describes whole essence of triplet–triplet transfer. This offers an impressive opportunity conduct a multitude diverse reactions and access sought-after molecular motifs.

Language: Английский

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Catalytic enantioselective C(sp3)–H functionalization involving radical intermediates

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: Jan. 20, 2021

Abstract Recently, with the boosted development of radical chemistry, enantioselective functionalization C( sp 3 )–H bonds via a pathway has witnessed renaissance. In principle, two distinct catalytic modes, distinguished by steps in which stereochemistry is determined (the formation step or step), can be devised. This Perspective discusses state-of-the-art area involving intermediates as well future challenges and opportunities.

Language: Английский

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Enantioselective access to chiral aliphatic amines and alcohols via Ni-catalyzed hydroalkylations

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: May 13, 2021

Abstract Chiral aliphatic amine and alcohol derivatives are ubiquitous in pharmaceuticals, pesticides, natural products fine chemicals, yet difficult to access due the challenge differentiate between spatially electronically similar alkyl groups. Herein, we report a nickel-catalyzed enantioselective hydroalkylation of acyl enamines enol esters with halides afford enantioenriched α-branched amines good yields excellent levels enantioselectivity. The operationally simple protocol provides straightforward chiral secondary alkyl-substituted from starting materials great functional group tolerance.

Language: Английский

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Reactivity of oximes for diverse methodologies and synthetic applications

Nature Synthesis, Journal Year: 2022, Volume and Issue: 1(1), P. 24 - 36

Published: Jan. 12, 2022

Language: Английский

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Modular Access to Chiral α-(Hetero)aryl Amines via Ni/Photoredox-Catalyzed Enantioselective Cross-Coupling

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(19), P. 8797 - 8806

Published: May 3, 2022

Chiral α-aryl N-heterocycles are commonly found in natural products, pharmaceutical agents, and chiral catalysts but remain challenging to access via asymmetric catalysis. Herein, we report a general modular approach for the direct enantioselective α-arylation of saturated azacycles acyclic N-alkyl benzamides nickel/photoredox dual This process exploits hydrogen atom transfer ability photoeliminated chlorine radicals convert corresponding α-amino alkyl that then coupled with ubiquitous inexpensive (hetero)aryl chlorides. These coupling reactions require no oxidants or organometallic reagents, feature feedstock starting materials, broad substrate scope, high enantioselectivities, applicable late-stage diversification medicinally relevant complex molecules. Mechanistic studies suggest nickel catalyst uncommonly plays multiple roles, accomplishing radical generation, capture, cross-coupling, induction.

Language: Английский

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N–O Bond Activation by Energy Transfer Photocatalysis

Accounts of Chemical Research, Journal Year: 2022, Volume and Issue: 55(17), P. 2526 - 2541

Published: Aug. 20, 2022

ConspectusA radical shift toward energy transfer photocatalysis from electron under visible-light photoirradiation is often due to the greener prospects of atom and process economy. Recent advances in embrace unique strategies for direct small-molecule activation sometimes extraordinary chemical bond formation absence additional/sacrificial reagents. Selective requires careful selection substrates photocatalysts a perfect match with respect their triplet energies while having incompatible redox potentials prevent competitive pathways. Substrates containing labile N–O bonds are potential targets generating reactive key intermediates via access variety functionalized molecules. Typically, differential densities N O heteroatoms have been exploited generation either N- or O-centered by pathway. However, latest developments involve homolysis generate both radicals subsequent utilization diverse organic transformations, also sacrificial In this Account, we highlight our contributions field intermediates, coverage useful mechanistic insights. More specifically, well-designed bond-containing such as 1,2,4-oxadiazolines, oxime esters, N-indolyl carbonates, N-enoxybenzotriazoles were successfully utilized versatile transformations involving selective over high state energy. Direct N-, O-, C-centered (if decarboxylation follows) was achieved cross-couplings rearrangement processes. particular, open-shell nitrogen including N(sp2) N(sp3) nitrenes, utilized. Notably, diversified identical through control reaction conditions. 1,2,4-Oxadiazolines converted into spiro-azolactams iminyl presence 1O2, benzimidazoles, sulfoximines external sulfoxide reagent nitrene inert Besides, esters underwent intramolecular C(sp3)–N radical–radical coupling intermolecular combined transfer–hydrogen strategy. Furthermore, series electrochemical photophysical experiments well computational studies performed substantiate proposed energy-transfer-driven We hope that Account will serve guide rational design processes further bonds.

Language: Английский

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Metallaphotoredox catalysis for sp³C–H functionalizations through hydrogen atom transfer (HAT)

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(12), P. 4099 - 4120

Published: Jan. 1, 2023

sp 3 C–H functionalizations under the combination of photocatalytic HAT and transition metal catalysis.

Language: Английский

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Photoinduced Cobalt-Catalyzed Desymmetrization of Dialdehydes to Access Axial Chirality

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(12), P. 6944 - 6952

Published: March 15, 2023

Enantioselective metallaphotoredox catalysis, which combines photoredox catalysis and asymmetric transition-metal has become an effective approach to achieve stereoconvergence under mild conditions. Although many impressive synthetic approaches have been developed access central chirality, the construction of axial chirality by still remains underexplored. Herein, we report two visible light-induced cobalt-catalyzed reductive couplings biaryl dialdehydes synthesize axially chiral aldehydes (60 examples, up 98% yield, >19:1 dr, >99% ee). This protocol shows good functional group tolerance, broad substrate scope, excellent diastereo- enantioselectivity.

Language: Английский

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