Abstract

A novel method for a synthesis of N-methyl 2-substituted indole was developed by a palladium catalyzed cross-coupling reaction of an enol triflate derived from the N-methyl-2-indolone with (alkenyl)tributylstannanes and acetylenes in good to excellent yields. In addition, the enol triflate derived from lactam exhibited less reactivity with respect to cross-coupling reactions as compared with those of the enol triflates of 2-coumaranone and 2-indanone.

Keywords: Enol triflate, indolone, coupling reaction, alkenyl stannane, acetylene