Electrochemical NiH-Catalyzed C(sp3)-C(sp3) Coupling of Alkyl Halides and Alkyl Alkenes.

Abstract

Herein, an electrochemically driven NiH-catalyzed reductive coupling of alkyl halides and alkyl alkenes for the construction of Csp3-Csp3 bonds is firstly reported. Notably, alkyl halides serve dual function as coupling substrates and as hydrogen sources to generate NiH species under electrochemical conditions. The tunable nature of this reaction is realized by introducing an intramolecular coordinating group to the substrate, where the product can be easily adjusted to give the desired branched product. The method proceeds under mild conditions, exhibits a broad substrate scope, and affords moderate to excellent yields with over 70 examples, including late-stage modification of natural products and drug derivatives. Mechanistic insights offer evidence for an electrochemically driven coupling process. The sp3-carbon-halogen bonds can be activated through single electron transfer (SET) by the nickel catalyst in its low valence state, generated by cathodic reduction, and the generation of NiH species from alkyl halides is pivotal to this transformation.