Native-carboxylate-assisted enantioselective C–H annulations with allenes and 1,3-dienes on ferrocene

Abstract

Native carboxylate as a directing group in enantioselective C–H activation results in poor stereodiscrimination, due to dynamic ligand exchange during the enantiodetermining concerted metalation–deprotonation (CMD) step. Herein, we present the synthesis of a new class of chiral ferrocene-fused isochroman derivatives from the readily available native carboxylate functionality. The Pd(II)/MPAA-derived enantioselective C–H activation and intermolecular annulation with allenes and 1,3-dienes afforded structurally diverse ferrocene-fused isochromans with up to 80% yield and 96 : 4 enantioselectivity.