The reactions of various stabilized ester enolates of 2-keto, 2-(alkox
ycarbonyl), 2-phosphoryl, and 2-(benzenesulfonyl) esters with cupric c
hloride or cupric bromide have been examined. The reactions lead to 2-
halo esters in good to excellent yields under mild condition. Enolates
which contain an unsaturated functionality such as a double bond, a t
riple bond, or an allylic or a benzylic moiety react with high chemose
lectivity.