Amide-Controlled Highly Selective Catalytic Borylcupration of Allenes

A novel copper‐catalyzed, highly regio‐ and stereoselective borylcupration of substituted 2,3‐allenamides with bis(pinacolato)diboron producing Z‐β‐borylated β,γ‐unsaturated enoamides has been demonstrated. Due to the unique effect of the amide‐group, perfect regio‐ and stereoselectivity and good to excellent yields have been achieved, which were rationalized by a DFT study. Perfect selection! A copper‐catalyzed, highly regio‐ and stereoselective borylcupration of 2,3‐allenamide with bis(pinacolato)diboron producing Z‐β‐borylated β,γ‐unsaturated amides has been developed (see scheme; L=large, S=small). Due to the unique effect of the amide group, perfect regio‐ and stereoselectivity and good to excellent yields have been achieved. The results have been rationalized by a DFT study.