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Catalytic, asymmetric difluorination of alkenes to generate difluoromethylated stereocenters.

ABSTRACT: Difluoromethyl groups possess specific steric and electronic properties that invite their use as chemically inert surrogates of alcohols, thiols, and other polar functional groups important in a wide assortment of molecular recognition processes. We report here a method for the catalytic, asymmetric, migratory geminal difluorination of ?-substituted styrenes to access a variety of products bearing difluoromethylated tertiary or quaternary stereocenters. The reaction uses commercially available reagents (m-chloroperbenzoic acid and hydrogen fluoride pyridine) and a simple chiral aryl iodide catalyst and is carried out readily on a gram scale. Substituent effects and temperature-dependent variations in enantioselectivity suggest that cation-? interactions play an important role in stereodifferentiation by the catalyst.

SUBMITTER: Banik SM

PROVIDER: S-EPMC5096785 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Catalytic, asymmetric difluorination of alkenes to generate difluoromethylated stereocenters.

Banik Steven M SM Medley Jonathan William JW Jacobsen Eric N EN

Science (New York, N.Y.) 20160701 6294

Difluoromethyl groups possess specific steric and electronic properties that invite their use as chemically inert surrogates of alcohols, thiols, and other polar functional groups important in a wide assortment of molecular recognition processes. We report here a method for the catalytic, asymmetric, migratory geminal difluorination of β-substituted styrenes to access a variety of products bearing difluoromethylated tertiary or quaternary stereocenters. The reaction uses commercially available r ...[more]

PMID: 27365443

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