Pyridine-boryl radicals-mediated reductive homocoupling of para-quinone methides

Abstract

An effective and straightforward pyridine-boryl radicals-mediated reductive homocoupling of para-quinone methides was developed, affording a broad range of differently substituted tetraarylethane derivatives in good to nearly quantitative yields. This metal-free procedure is characterized by operational simplicity, ready availability of starting materials, high atom economy and broad substrate scope under mild reaction conditions. Moreover, the products were easily further transformation into valuable tetraphenylethylenes, possessing aggregation-induced emission (AIE) behaviour. Additionally, gram-scale reaction and control experiment are also studied.