Paired Electrolysis Enables Reductive Heck Coupling of Unacti-vated (Hetero)Aryl Halides and Alkenes

The formation of carbon-carbon (C–C) bonds is a cornerstone of organic synthesis. Among various methods to construct Csp2–Csp3 bonds, the reductive Heck reaction between (hetero)aryl halides and alkenes stands out due to its potential efficiency and broad substrate availability. However, traditional reductive Heck reactions are limited by the use of pre-cious metal catalysts and/or limited aryl halide and alkene compatibility. Here, we present an electrochemically mediat-ed, metal- and catalyst-free reductive Heck reaction that tolerates both unactivated (hetero)aryl halides and diverse al-kenes such as vinyl boronates. Detailed electrochemical and deuterium-labeling studies support that this transformation likely proceeds through a paired electrolysis pathway, in which acid generated by the oxidation of N,N-diisopropylethylamine (DIPEA) at the anode intercepts an alkyl carbanion formed after radical-polar crossover at the cathode. As such, this approach offers a sustainable method for the construction of Csp2–Csp3 bonds from (hetero)aryl halides and alkenes, paving the way for the development of other electrochemically mediated olefin difunctionalization reactions.