Reaction of polyfluorinated α-halo-β-keto esters with ammonia

1. The reaction of polyfluorinated α-chloro-β-keto esters with ammonia in the case of a difluoromethyl substituent gives 2-chloro-4,4-difluoro-3-aminocrotonic ester as the major product. When CF3 and higher fluoroalkyl substituents are present at the β-carbon of the β-keto ester, the esters are cleaved by NH3 to amides of fluorocarboxylic acids and chloroacetamide. 2. Fluoroalkyl derivatives of 2,2-dibromo-β-keto esters undergo cleavage by the action of NH3 to give amides of fluorocarboxylic acids and dibromoacetamide, regardless of the type of fluoroalkyl substituent.