Iridium-Catalyzed Intramolecular Asymmetric Allylic Dearomatization of Benzene Derivatives

Abstract

Guided by the mechanistic insights from computational studies, we have developed an Ir-catalyzed asymmetric intramolecular allylic dearomatization reaction of benzene derivatives. Under the optimized conditions consisting of a readily available Ir catalyst, a series of spiro[4.5]cyclohexadiene compounds were delivered in reasonable yields (up to 79 %) with good enantioselectivity (up to 99 % ee). The introduction of a malonate diester-type substituent serves as a key strategy to guide the nucleophilic reactivity of the benzene ring.

Keywords: DFT calculations; asymmetric catalysis; benzene; dearomatization; homogeneous catalysis.