Silver-modified polyniobotungstate for the visible light-induced simultaneous cleavage of C–C and C–N bonds

作者：Shujun Li, Na Li, Gang Li, Yubin Ma, Mengyao Huang, Qingchun Xia, Qianyi Zhao, Xuenian Chen · 发表于：Polyoxometalates · 年份：2023 · DOI：10.26599/pom.2023.9140024 · 被引用次数：26 · 研究领域：Polyoxometalates: Synthesis and Applications、Metal-Organic Frameworks: Synthesis and Applications、Sulfur-Based Synthesis Techniques

Silver-modified polyniobotungstate based on Nb/W mixed-addendum polyoxometalate with formula Ag 9 [P 2 W 15 Nb 3 O 62 ]·21H 2 O ( Ag-Nb/W ) was synthesized and then characterized by various analytical and spectral techniques. Ag-Nb/W was proven to be an efficient photocatalyst for the oxidative ring opening of 2-phenylimidazo[1,2- a ]pyridine via the simultaneous cleavage of C–C and C–N bonds. Under visible light (430–440 nm) and with oxygen as an oxidant at room temperature, Ag-Nb/W can catalyze the rapid transformation of various 2-phenylimidazo[1,2- a ]pyridine derivatives to produce the corresponding oxidative ring-opening product N-(pyridin-2-yl) amides in good isolated yields ranging from 65% to 78%. As a heterogeneous photocatalyst, Ag-Nb/W showed excellent sustainability and recyclability in the recycling experiments. Infrared (IR) spectroscopy and X-ray diffraction (XRD) analysis indicated that Ag-Nb/W could retain its integrity after catalysis. A possible mechanism involving the singlet oxygen for the catalytic reaction was proposed.