Selective alpha-amination and a-acylation of esters and amides via dual reactivity of O-acylhydroxylamines toward zinc enolates

Selective alpha-amination and alpha-acylation of esters and amides have been developed, employing O-acylhydroxylamines as a dually reactive aminating and acylating reagent. Treatment of zinc enolates with O-acylhydroxylamines provides solely 1,3-dicarbonyl compounds under mild conditions. Introduction of a copper catalyst into the system shifts the reactivity entirely, yielding a-amination products exclusively.