Efficient synthesis of a (Z)-3-methyleneisoindolin-1-one library using Cu(OAc)₂•H₂O/DBU under microwave irradiation.

Microwave-promoted efficient synthesis of a (Z)-3-methyleneisoindolin-1-one library from 2-bromobenzamides and terminal alkynes using Cu(OAc)₂•H₂O/DBU is described. Various benzamide substituents, ring substitutions, including heteroaryl, aryl acetylenes and aliphatic alkynes, could be applied to afford the desired products in good to moderate yield with high stereoselectivity. It is noteworthy that DBU maybe play a dual role as not only the base, but also as a ligand for copper. The reaction is catalyzed by the complex of Cu(OAc)₂•H₂O and DBU without other additives.