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Electroreductive cross-electrophile coupling has emerged as a powerful and efficient method for constructing challenging C–C or C–X bonds, providing several advantages including highly efficient electron transfer, tunable reducing potential, direct electricity-activation of substrates and good scalability. In electroreductive cross-electrophile coupling, a high loading of a transition metal catalyst is required to facilitate the transfer of electrons from the cathode to organic halides, making it unsuitable for sensitive organic halides such as chloroformates. As a result, the electroreductive XEC of readily accessible chloroformates with alkyl halides for ester synthesis remains a largely unmet challenge. In this work, catalyst-free electrochemically driven cross-electrophile esterification of alkyl halides has been developed. A wide range of 2-phenylacetic esters which represent an important class of molecules in synthetic and medicinal chemistry are accessed from simple and cheap alkyl halides and alkyl chloroformates under mild reaction conditions. Various functional groups were well tolerated, affording up to 98% yields. This protocol would contribute a lot for the further development of electrochemically driven cross-electrophile coupling. [ABSTRACT FROM AUTHOR]

The electroreductive cross-electrophile coupling which has emerged as a powerful, green and efficient method for constructing challenging C–C bonds has attracted increasing attention from organic chemists. Most of the previous works focus on direct two-electrophile cross-coupling. In this work, the nickel-catalyzed three-electrophile electroreductive cross-electrophile coupling which offers direct convergent synthesis to target molecules from easily-available and cheap substrates has been developed. A wide range of alkyl aryl ketones are accessed from alkyl halides, aryl iodides and propyl chloroformate under mild conditions, avoiding the use of over-stoichiometric reductants, excess quantities of additives and activators, and superstoichiometric CO gas or metal carbonyl complexes which are toxic, environmentally unfriendly and can be inconvenient to handle. The scale-up experiment indicates the good scalability of electrosynthesis compared to traditional synthesis. High chemo-selectivity can be achieved through an increase in the current. Mechanistic investigation suggests that the electron transfer rate from the cathode to Ni catalysts plays a vital role in this protocol. Our approach demonstrates a novel electrochemical selectivity-controlled strategy in cross-electrophile coupling. [ABSTRACT FROM AUTHOR]