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Photoredox Generation of Carbon-Centered Radicals Enables the Construction of 1,1-Difluoroalkene Carbonyl Mimics.

ABSTRACT: Described is a facile, scalable route to access functional-group-rich gem-difluoroalkenes. Using visible-light-activated catalysts in conjunction with an arsenal of carbon-radical precursors, an array of trifluoromethyl-substituted alkenes undergoes radical defluorinative alkylation. Nonstabilized primary, secondary, and tertiary radicals can be used to install functional groups in a convergent manner, which would otherwise be challenging by two-electron pathways. The process readily extends to other perfluoroalkyl-substituted alkenes. In addition, we report the development of an organotrifluoroborate reagent to expedite the synthesis of the requisite trifluoromethyl-substituted alkene starting materials.

SUBMITTER: Lang SB

PROVIDER: S-EPMC5688010 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Photoredox Generation of Carbon-Centered Radicals Enables the Construction of 1,1-Difluoroalkene Carbonyl Mimics.

Lang Simon B SB Wiles Rebecca J RJ Kelly Christopher B CB Molander Gary A GA

Angewandte Chemie (International ed. in English) 20171024 47

Described is a facile, scalable route to access functional-group-rich gem-difluoroalkenes. Using visible-light-activated catalysts in conjunction with an arsenal of carbon-radical precursors, an array of trifluoromethyl-substituted alkenes undergoes radical defluorinative alkylation. Nonstabilized primary, secondary, and tertiary radicals can be used to install functional groups in a convergent manner, which would otherwise be challenging by two-electron pathways. The process readily extends to ...[more]

PMID: 28960656

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