Photoredox-catalyzed selective head-to-head reductive coupling of activated alkenes†

Abstract

Head-to-head reductive hydrodimerization of activated alkenes offers access to valuable bulk or fine chemicals such as adipates or adiponitrile as an intermediate for the industrial synthesis of nylon. We herein report a novel reaction to realize head-to-head reductive coupling of activated alkenes by a photoinduced Ir/PPh₃/H₂O system, providing smooth access to various adipate derivatives in high chemo- and regioselectivity. In this reaction, a [Ph₃P-OH] radical generated from a photoinduced interaction between H₂O and PPh₃ enables the PCET process with activated alkenes to form a C-centered radical at the β-position, which is rarely reported.