Ni-Catalyzed Reductive Coupling of Acetals with Anhydrides and Vinyl Triflates via Single-Electron C–O Activation

We report a Ni-catalyzed reductive cross-coupling of benzaldehyde-derived acetals with anhydrides or vinyl triflates, enabling modular access to α-substituted ethers. Lewis acid/Zn-mediated activation generates α-oxy radicals for selective C(sp3)-C(sp2) bond formation via Ni catalysis. This polarity-convergent method unifies ether-variants of benzoin condensation and classical NHK reactions under one reductive platform. Broad scope is demonstrated, and tuning the Lewis acid extends reactivity to dialkyl acetals. Stoichiometric, organometallic, and spectroscopic studies support the reaction mechanism.