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Enantioselective radical process for synthesis of chiral indolines by metalloradical alkylation of diverse C(sp3)-H bonds.

ABSTRACT: A new C-C bond formation strategy based on enantioselective radical alkylation of C(sp3)-H bonds via Co(ii)-based metalloradical catalysis has been demonstrated for stereoselective synthesis of chiral indolines. The Co(ii)-based system enables activation of aryldiazomethanes as radical precursors at room temperature for enantioselective intramolecular radical alkylation of broad types of C-H bonds, constructing 2-substituted indolines in high yields with excellent enantioselectivities. In addition to chemoselectivity and regioselectivity, this Co(ii)-catalyzed alkylation features tolerance to functional groups and compatibility with heteroaryl substrates. Detailed mechanistic studies provide insight into the underlying stepwise radical pathway.

SUBMITTER: Wen X

PROVIDER: S-EPMC5994879 | biostudies-other | 2018 Jun

REPOSITORIES: biostudies-other

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Enantioselective radical process for synthesis of chiral indolines by metalloradical alkylation of diverse C(sp3)-H bonds.

Wen Xin X Wang Yong Y Zhang X Peter XP

Chemical science 20180514 22

A new C-C bond formation strategy based on enantioselective radical alkylation of C(sp3)-H bonds via Co(ii)-based metalloradical catalysis has been demonstrated for stereoselective synthesis of chiral indolines. The Co(ii)-based system enables activation of aryldiazomethanes as radical precursors at room temperature for enantioselective intramolecular radical alkylation of broad types of C-H bonds, constructing 2-substituted indolines in high yields with excellent enantioselect ...[more]

PMID: 29938039

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