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Asymmetric Suzuki cross-couplings of activated secondary alkyl electrophiles: arylations of racemic alpha-chloroamides.

ABSTRACT: A nickel-catalyzed stereoconvergent method for the enantioselective Suzuki arylation of racemic alpha-chloroamides has been developed. This process provides a unique example of an asymmetric arylation of an alpha-haloamide, an enantioselective arylation of an alpha-chlorocarbonyl compound, and an asymmetric Suzuki reaction with an activated alkyl electrophile or an arylboron reagent. The method is also applicable to the corresponding enantioselective cross-coupling of alpha-bromoamides. The coupling products can be transformed without racemization into enantioenriched alpha-arylcarboxylic acids and primary alcohols. A modest kinetic resolution of the alpha-chloroamide was observed; a mechanistic study indicated that the selectivity may reflect discrimination by the chiral catalyst of the two enantiomeric alpha-chloroamides in an irreversible oxidative-addition process.

SUBMITTER: Lundin PM

PROVIDER: S-EPMC2924160 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature

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Asymmetric Suzuki cross-couplings of activated secondary alkyl electrophiles: arylations of racemic alpha-chloroamides.

Lundin Pamela M PM Fu Gregory C GC

Journal of the American Chemical Society 20100801 32

A nickel-catalyzed stereoconvergent method for the enantioselective Suzuki arylation of racemic alpha-chloroamides has been developed. This process provides a unique example of an asymmetric arylation of an alpha-haloamide, an enantioselective arylation of an alpha-chlorocarbonyl compound, and an asymmetric Suzuki reaction with an activated alkyl electrophile or an arylboron reagent. The method is also applicable to the corresponding enantioselective cross-coupling of alpha-bromoamides. The coup ...[more]

PMID: 20698665

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