Rh(iii)-catalyzed alkynylation: synthesis of functionalized quinolines from aminohydrazones

Abstract

Rhodium-catalyzed, chemo- and regioselective synthesis of functionalized quinolines using 2-aminohydrazones and terminal alkynes has been described. The reaction is oxidant/base-free and tolerates a wide variety of functional groups and has been successfully extended with 1,3 and 1,4-bis(phenylethynyl)benzenes to afford 1,3- and 1,4-bis(4-methylquinolin-2-yl)benzenes and 2-(3/4-ethynylphenyl)-4-methylquinolines. Furthermore, the control experiment supports the proposed reaction mechanism.