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Cobalt-Catalyzed Stereoretentive Hydrogen Isotope Exchange of C(sp3)-H Bonds.

ABSTRACT: Cobalt dialkyl complexes bearing ?-diimine ligands proved to be active precatalysts for the nondirected, C(sp3)-H selective hydrogen isotope exchange (HIE) of alkylarenes using D2 gas as the deuterium source. Alkylarenes with a variety of substitution patterns and heteroatom substituents on the arene ring were successfully labeled, enabling high levels of incorporation into primary, secondary, and tertiary benzylic C(sp3)-H bonds. In some cases, the HIE proceeded with high diastereoselectivity and application of the cobalt-catalyzed method to enantioenriched substrates with benzylic stereocenters provided enantioretentive hydrogen isotope exchange at tertiary carbons.

SUBMITTER: Palmer WN

PROVIDER: S-EPMC5813831 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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