Visible-Light-Induced C−N Bonds Formation by Ce(III)-Containing Antimonotungstate with Ce-to-Polyanion Charge Transfer

Abstract

The direct transformation of C−H to C−N bond is a significant conversion for organic synthesis, pharmaceutical, and fine-chemical industries. It is imperative to explore economical and environmentally friendly catalytic systems that focus on reusable catalysts, waste reduction, and mild conditions. Herein, we present an efficient and eco-friendly method for promoting the direct conversion of C−H to C−N bond in water under irradiation of visible-light using a Ce(III)-containing antimonotungstate photocatalyst, [(CH3)2NH2]4Na21{[Ce4(H2O)8W6O12(tar)3(OAc)][B-α-SbW9O33]4}·51H2O (CeSbW, H4tar = tartaric acid, HOAc = acetic acid). CeSbW exhibits excellent photoelectric activity with a unique intramolecular charge transfer of CeIII-to-POM (WVI) upon visible light irradiation. With CeSbW as the photocatalyst, the visible-light-induced C−N bond formation via hydroacylation of dialkyl azodicarboxylates was successfully achieved, featuring a broad substrate scope, excellent reusability, and environmentally benign reaction conditions. This methodology not only enriches the synthesis strategy for visible-light-responsive POMs catalysts but also provides an efficient and sustainable photocatalytic system for C−N bond construction.