Coupling Reactions of α-(<i>N</i>-Carbamoyl)alkylcuprates with Enol Triflates Derived from Cyclic β-Keto Esters:  A Facile Approach to γ-Carbamoyl-α,β-enoates

α-(<i>N</i>-Carbamoylalkyl)cuprates couple with enol triflates derived from carbocyclic and heterocyclic (i.e., piperidinones) β-keto esters. Product yields are higher with the alkyl(cyano)cuprates [i.e., RCu(CN)Li, 56−93%] than with the dialkylcuprate reagents (i.e., R₂CuLi·LiCN). An enol nonaflate works as well as the corresponding enol triflate. A facile synthetic route to γ-amino α,β-enoates not readily prepared from γ-keto-α,β-enoates is thus established. The γ-amino-α,β-enoates, available via <i>N</i>-Boc deprotection, can be cyclized to annulated pyrrolin-2-ones.