Cu(ii)-Catalyzed formal [4 + 2] cycloaddition between quinone methides (QMs) and electron-poor 3-vinylindoles

Abstract

A new Cu(II)-catalyzed formal [4 + 2] cycloaddition between quinone methides (QMs) including para-quinone methides (p-QMs) and ortho-quinone methides (o-QMs) and electron-poor 3-vinylindoles was established. A wide range of richly decorated indole-containing chromane derivatives were synthesized in acceptable yields and diastereoselectivity. Based on several control experiments, a possible mechanism was also proposed to elucidate the catalytic cycle pathway.