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Metal-free defluorinative arylation of trifluoromethyl alkenes via photoredox catalysis.

ABSTRACT: Literature methods to access gem-difluoroalkenes are largely limited to harsh, organometallic-based methods, and known photoredox-mediated processes are not amenable to aryl radical addition to trifluoromethyl alkenes. A metal-free, functional group-tolerant method for the preparation of benzylic gem-difluoroalkenes is described. Halogen atom abstraction from (hetero)aryl halides generates aryl radicals that undergo a defluorinative arylation of ?-trifluoromethyl alkenes, tolerating electronically disparate aryl radicals and ?-trifluoromethyl alkenes.

SUBMITTER: Wiles RJ

PROVIDER: S-EPMC7210470 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Metal-free defluorinative arylation of trifluoromethyl alkenes via photoredox catalysis.

Wiles Rebecca J RJ Phelan James P JP Molander Gary A GA

Chemical communications (Cambridge, England) 20190614 53

Literature methods to access gem-difluoroalkenes are largely limited to harsh, organometallic-based methods, and known photoredox-mediated processes are not amenable to aryl radical addition to trifluoromethyl alkenes. A metal-free, functional group-tolerant method for the preparation of benzylic gem-difluoroalkenes is described. Halogen atom abstraction from (hetero)aryl halides generates aryl radicals that undergo a defluorinative arylation of α-trifluoromethyl alkenes, tolerating electronical ...[more]

PMID: 31199418

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