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Photoredox-Catalyzed Site-Selective ?-C(sp3 )-H Alkylation of Primary Amine Derivatives.

ABSTRACT: The synthetic utility of tertiary amines to oxidatively generate ?-amino radicals is well established, however, primary amines remain challenging because of competitive side reactions. This report describes the site-selective ?-functionalization of primary amine derivatives through the generation of ?-amino radical intermediates. Employing visible-light photoredox catalysis, primary sulfonamides are coupled with electron-deficient alkenes to efficiently and mildly construct C-C bonds. Interestingly, a divergence between intermolecular hydrogen-atom transfer (HAT) catalysis and intramolecular [1,5]?HAT was observed through precise manipulation of the protecting group. This dichotomy was leveraged to achieve excellent ?/? site-selectivity.

SUBMITTER: Ashley MA

PROVIDER: S-EPMC6442930 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Photoredox-Catalyzed Site-Selective α-C(sp3 )-H Alkylation of Primary Amine Derivatives.

Ashley Melissa A MA Yamauchi Chiaki C Chu John C K JCK Otsuka Shinya S Yorimitsu Hideki H Rovis Tomislav T

Angewandte Chemie (International ed. in English) 20190215 12

The synthetic utility of tertiary amines to oxidatively generate α-amino radicals is well established, however, primary amines remain challenging because of competitive side reactions. This report describes the site-selective α-functionalization of primary amine derivatives through the generation of α-amino radical intermediates. Employing visible-light photoredox catalysis, primary sulfonamides are coupled with electron-deficient alkenes to efficiently and mildly construct C-C bonds. Interestin ...[more]

PMID: 30768740

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