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Pd-catalyzed ?-arylation of ?,?-difluoroketones with aryl bromides and chlorides. A route to difluoromethylarenes.

ABSTRACT: We report the Pd-catalyzed ?-arylation of ?,?-difluoroketones with aryl and heteroaryl bromides and chlorides catalyzed by an air- and moisture-stable palladacyclic complex containing P(t-Bu)Cy2 as ligand. The combination of this Pd-catalyzed arylation and base-induced cleavage of the acyl-aryl C-C bond within the ?-aryl-?,?-difluoroketone constitutes a one-pot, two-step procedure to synthesize difluoromethylarenes from aryl halides. A broad range of electronically varied aryl and heteroaryl bromides and chlorides underwent these two transformations, providing ?-aryl-?,?-difluoroketones, difluoromethylarenes, and difluoromethylheteroarenes in high yields.

SUBMITTER: Ge S

PROVIDER: S-EPMC3985691 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Pd-catalyzed α-arylation of α,α-difluoroketones with aryl bromides and chlorides. A route to difluoromethylarenes.

Ge Shaozhong S Chaładaj Wojciech W Hartwig John F JF

Journal of the American Chemical Society 20140310 11

We report the Pd-catalyzed α-arylation of α,α-difluoroketones with aryl and heteroaryl bromides and chlorides catalyzed by an air- and moisture-stable palladacyclic complex containing P(t-Bu)Cy2 as ligand. The combination of this Pd-catalyzed arylation and base-induced cleavage of the acyl-aryl C-C bond within the α-aryl-α,α-difluoroketone constitutes a one-pot, two-step procedure to synthesize difluoromethylarenes from aryl halides. A broad range of electronically varied aryl and heteroaryl bro ...[more]

PMID: 24588379

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