A nickel-catalyzed stereoconvergent method for the enantioselective Suzuki arylation of racemic α-chloroamides has been developed. This process represents the first example of an asymmetric arylation of an α-haloamide, of an enantioselective arylation of an α-chlorocarbonyl compound, and of 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 α-bromoamides. The coupling products can be transformed without racemization into useful enantioenriched α-arylcarboxylic acids and primary alcohols. An unprecedented (and modest) kinetic resolution of the α-chloroamide has been observed; a mechanistic study indicates that the selectivity likely reflects the discrimination by the chiral catalyst of the two enantiomeric α-chloroamides in an irreversible oxidative-addition process.
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