1,6-Addition of Indolizines to para-Quinone Methides with Indium(III) Chloride as Catalyst

A 1,6-addition of a wide variety of indolizines to para-quinone methides was developed using only 2 mol% indium chloride as a catalyst. The method successfully allows the regioselective addition of indolizines at positions 1 and 3 to p-quinone methides, leading to the formation of the desired products in excellent yields in most cases (up to 99%) under mild conitions and in short reaction time.