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Regioselective Alkylative Cross-Coupling of Remote Unactivated C(sp3)-H Bonds.

ABSTRACT: The functionalization of unactivated C(sp3)-H bonds poses a significant challenge due to their ubiquity and relative similarity in most organic frameworks. Herein, we describe the use of a combined photoredox and nickel catalytic system for the regioselective C(sp3)-C(sp3) coupling of unactivated C(sp3)-H bonds and alkyl bromides. Positional selectivity is dictated by a 1,5-hydrogen atom transfer (HAT) reaction by a pendent amide. Interception of this radical by a Ni catalyst allows distal alkylation to occur in good yield and excellent selectivity.

SUBMITTER: Thullen SM

PROVIDER: S-EPMC7097885 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Regioselective Alkylative Cross-Coupling of Remote Unactivated C(sp3)-H Bonds.

Thullen Scott M SM Treacy Sean M SM Rovis Tomislav T

Journal of the American Chemical Society 20190903 36

The functionalization of unactivated C(sp3)-H bonds poses a significant challenge due to their ubiquity and relative similarity in most organic frameworks. Herein, we describe the use of a combined photoredox and nickel catalytic system for the regioselective C(sp3)-C(sp3) coupling of unactivated C(sp3)-H bonds and alkyl bromides. Positional selectivity is dictated by a 1,5-hydrogen atom transfer (HAT) reaction by a pendent ...[more]

PMID: 31478370

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