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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Dynamic Kinetic Reductive Conjugate Addition for Construction of Axial Chirality Enabled by Synergistic Photoredox/Cobalt Catalysis

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(14), P. 7983 - 7991

Published: March 28, 2023

Conjugate addition is among the most important synthetic protocols for constructing carbon skeletons and widely used to synthesize natural products drugs. However, asymmetric catalysis studies have mainly focused on stereogenic centers arising from conjugate alkenes. Here, we report first photoinduced cobalt-catalyzed dynamic kinetic reductive reaction that enables formation of heterobiaryls with axial chirality (45 examples, up 91% yield 97% ee). This method features mild conditions, good functional-group tolerance, excellent enantiomeric control. Significantly, large amounts metal waste precious catalysts can be avoided under these conditions. Migration chiral arylcobalt species into alkene might rate-determining step based studies.

Language: Английский

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Stereodynamic Strategies to Induce and Enrich Chirality of Atropisomers at a Late Stage

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(17), P. 10641 - 10727

Published: Aug. 28, 2023

Enantiomers, where chirality arises from restricted rotation around a single bond, are atropisomers. Due to the unique nature of origins their chirality, synthetic strategies access these compounds in an enantioselective manner differ those used prepare enantioenriched containing point arising unsymmetrically substituted carbon center. In particular stereodynamic transformations, such as dynamic kinetic resolutions, thermodynamic and deracemizations, which rely on ability racemize or interconvert enantiomers, promising set transformations optically pure late stage sequence. Translation approaches with atropisomers requires expanded toolbox for epimerization/racemization provides opportunity develop new conceptual framework synthesis compounds.

Language: Английский

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Catalytic atroposelective synthesis

Nature Catalysis, Journal Year: 2024, Volume and Issue: 7(5), P. 483 - 498

Published: April 30, 2024

Language: Английский

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Cobalt‐Catalyzed Asymmetric Aza‐Nozaki–Hiyama–Kishi (NHK) Reaction of α‐Imino Esters with Alkenyl Halides

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(7)

Published: Jan. 2, 2024

Chromium-catalyzed enantioselective Nozaki-Hiyama-Kishi (NHK) reaction represents one of the most powerful approaches for formation chiral carbon-heteroatom bond. However, construction sterically encumbered tetrasubstituted stereocenter through NHK still posts a significant challenge. Herein, we disclose cobalt-catalyzed aza-NHK ketimine with alkenyl halide to provide convenient synthetic approach manufacture enantioenriched α-vinylic amino acid. This protocol exhibits excellent functional group tolerance 99 % ee in cases. Additionally, this asymmetric reductive method is also applicable aldimine access trisubstituted stereogenic centers.

Language: Английский

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Atroposelective catalysis

Nature Reviews Chemistry, Journal Year: 2024, Volume and Issue: 8(7), P. 497 - 517

Published: June 18, 2024

Language: Английский

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Desymmetrization–Addition Reaction of Cyclopropenes to Imines via Synergistic Photoredox and Cobalt Catalysis

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(28), P. 18892 - 18898

Published: July 5, 2024

Herein, we designed a reaction for the desymmetrization-addition of cyclopropenes to imines by leveraging synergy between photoredox and asymmetric cobalt catalysis. This protocol facilitated synthesis series chiral functionalized cyclopropanes with high yield, enantioselectivity, diastereoselectivity (44 examples, up 93% yield >99% ee). A possible mechanism involving cyclopropene desymmetrization Co-H species imine addition Co-alkyl was proposed. study provides novel route important extends frontier metallaphotoredox

Language: Английский

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Dynamic Kinetic Reductive Grignard-Type Addition for the Construction of Axial and Central Chirality

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 1147 - 1157

Published: Jan. 3, 2025

This study describes a photoredox/cobalt dual-catalyzed asymmetric Grignard-type addition reaction, enabling the synthesis of axially chiral hexatomic (six–six) N-heterobiaryls bearing extra secondary alcohol unit via an efficient dynamic kinetic transformation racemic N-heterobiaryl triflate substrates. The conversion facilitated both photoredox and classical reductive reaction conditions exhibits good functional group tolerance, broad substrate scope, satisfactory stereoselectivity. Furthermore, control experiments density theory calculations provide preliminary mechanistic insights.

Language: Английский

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Synthesis of Axially Chiral Biaryls through Cobalt(II)‐Catalyzed Atroposelective C−H Arylation

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(40)

Published: Aug. 16, 2023

Highly efficient synthesis of axially chiral biaryl amines through cobalt-catalyzed atroposelective C-H arylation using easily accessible cobalt(II) salt and salicyloxazoline ligand has been reported. This methodology provides a straightforward sustainable access to broad range enantioenriched biaryl-2-amines in good yields (up 99 %) with excellent enantioselectivities % ee). The synthetic utility the unprecedented method is highlighted by its scalability diverse transformations.

Language: Английский

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Construction of C-B axial chirality via dynamic kinetic asymmetric cross-coupling mediated by tetracoordinate boron

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: July 24, 2023

Abstract Catalytic dynamic kinetic asymmetric transformation (DyKAT) provides a powerful tool to access chiral stereoisomers from racemic substrates. Such has been widely employed on the construction of central chirality, however, application in axial chirality remains underexplored because its equilibrium substrate enantiomers is limited five-membered metalacyclic intermediate. Here we report tetracoordinate boron-directed cross-coupling racemic, configurationally stable 3-bromo-2,1-azaborines with boronic acid derivatives. A series challenging C-B axially compounds were prepared generally good excellent enantioselectivities. Moreover, this can also be extended prepare atropisomers bearing adjacent and C-C diaxes diastereo- enantio-control. The key success relies rational design reversible boron intermediate, which supported by theoretical calculations that dramatically reduces rotational barrier original axis achieves goal DyKAT.

Language: Английский

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