Unsaturated Carboxylates as Electrophilic Synthons for Transition-Metal-Catalyst-Free Electroreductive Deoxygenative
Jianyou Zhao1, Jiaoyang Liu1, Zi-Ao Zhang1
1Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China.
Abstract:
The use of ester-derived electrophiles in transition-metal-free electroreductive C(sp3)─C(sp3) bond formation remains largely unexplored. Herein, we report a sacrificial-anode-enabled electroreductive cross-coupling of simple unsaturated carboxylates with unactivated alkyl halides. Aryl, alkenyl, and alkynyl carboxylates are readily incorporated, affording methylene-bridged alkylarenes together with allylic and propargylic C(sp3)-rich frameworks under mild conditions. Mechanistic studies support independent single-electron reduction of both electrophilic partners, followed by radical-radical coupling, alkoxide elimination, and cathodic deoxygenation via a Clemmensen-like reduction pathway. This work establishes unsaturated carboxylates as a new class of alkylating reagents for electroreductive C(sp3)─C(sp3) bond formation.
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