Photoelectrocatalysis-Enabled C(sp3)-C(sp3) Cross-Coupling of Carboxylic Acids with Alkyl Halides
Jian-Feng Guo1, Yi-Fan Chen1, Cheng-Bo Sun1
1State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, P. R. China.
Abstract:
The construction of C(sp3)-C(sp3) bonds remains a fundamental challenge in synthetic chemistry. Herein, we interrogate a photoelectrochemical strategy for the cross-coupling of aliphatic carboxylic acids with alkyl halides. This dual catalytic system synergistically integrates anodic photoinduced ligand-to-metal charge transfer (LMCT) with cathodic nickel-mediated electroreduction. Exploiting the photolysis of a carboxylate-metal complex, our approach enables the mild generation of alkyl radicals at the anode, bypassing the necessity for high-energy irradiation or harsh oxidative conditions. Concurrently, the cathode facilitates the selective reduction of Ni(II) to Ni(I), which engages the alkyl halide and mediates the subsequent radical cross-coupling. This protocol provides an alternative method for assembling complex molecular architectures under exceptionally mild conditions, representing a distinct advance in synthetic photoelectrochemistry.
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