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Visible-light promoted regioselective amination and alkylation of remote C(sp3)-H bonds.

ABSTRACT: The C-N cross coupling reaction has always been a fundamental task in organic synthesis. However, the direct use of N-H group of aryl amines to generate N-centered radicals which would couple with alkyl radicals to construct C-N bonds is still rare. Here we report a visible light-promoted C-N radical cross coupling for regioselective amination of remote C(sp3)-H bonds. Under visible light irradiation, the N-H groups of aryl amines are converted to N-centered radicals, and are then trapped by alkyl radicals, which are generated from Hofmann-Löffler-Freytag (HLF) type 1,5-hydrogen atom transfer (1,5-HAT). With the same strategy, the regioselective C(sp3)-C(sp3) cross coupling is also realized by using alkyl Hantzsch esters (or nitrile) as radical alkylation reagents. Notably, the ?-C(sp3)-H of tertiary amines can be directly alkylated to form the C(sp3)-C(sp3) bonds via C(sp3)-H?-?C(sp3)-H cross coupling through the same photoredox pathway.

SUBMITTER: Guo Q

PROVIDER: S-EPMC7081228 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Visible-light promoted regioselective amination and alkylation of remote C(sp3)-H bonds.

Guo Quanping Q Peng Qiang Q Chai Hongli H Huo Yumei Y Wang Shan S Xu Zhaoqing Z

Nature communications 20200319 1

The C-N cross coupling reaction has always been a fundamental task in organic synthesis. However, the direct use of N-H group of aryl amines to generate N-centered radicals which would couple with alkyl radicals to construct C-N bonds is still rare. Here we report a visible light-promoted C-N radical cross coupling for regioselective amination of remote C(sp3)-H bonds. Under visible light irradiation, the N-H groups of aryl amines are converted to N-centered radicals, and are then tra ...[more]

PMID: 32193371

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