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Pd-catalyzed ?-arylation of trimethylsilyl enolates of ?,?-difluoroacetamides.

ABSTRACT: We report the arylation and heteroarylation of ?,?-difluoro-?-(trimethylsilyl)acetamides with aryl and heteroaryl bromides catalyzed by an air- and moisture-stable palladacyclic complex containing P(t-Bu)2Cy as ligand. A broad range of electronically varied aryl and heteroaryl bromides underwent this transformation to afford ?-aryl-?,?-difluoroacetamides in high yields. Due to the electrophilicity of the fluorinated amide, this palladium-catalyzed cross-coupling reaction provides a versatile platform to generate a range of ?,?-difluoro carbonyl compounds, such as ?-aryl-?,?-difluoroketones, -acetaldehydes, -acetates, and acetic acids, and difluoroalkyl derivatives, such as 2-aryl-2,2-difluoroethanols and -ethylamines, under mild conditions.

SUBMITTER: Ge S

PROVIDER: S-EPMC4210146 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Pd-catalyzed α-arylation of trimethylsilyl enolates of α,α-difluoroacetamides.

Ge Shaozhong S Arlow Sophie I SI Mormino Michael G MG Hartwig John F JF

Journal of the American Chemical Society 20141003 41

We report the arylation and heteroarylation of α,α-difluoro-α-(trimethylsilyl)acetamides with aryl and heteroaryl bromides catalyzed by an air- and moisture-stable palladacyclic complex containing P(t-Bu)2Cy as ligand. A broad range of electronically varied aryl and heteroaryl bromides underwent this transformation to afford α-aryl-α,α-difluoroacetamides in high yields. Due to the electrophilicity of the fluorinated amide, this palladium-catalyzed cross-coupling reaction provides a versatile pla ...[more]

PMID: 25254966

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