Two transition-metal-modified Nb/W mixed-addendum polyoxometalates for visible-light-mediated aerobic benzylic C–H oxidations  

作　　者：Yubin Ma Fan Gao Wanru Xiao Na Li Shujun Li Bing Yu Xuenian Chen 

机构地区：[1]School of Chemistry and Chemical Engineering,Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials,Henan Normal University,Xinxiang 453007,China [2]College of Chemistry,Zhengzhou University,Zhengzhou 450001,China

出　　处：《Chinese Chemical Letters》2022年第9期4395-4399,共5页中国化学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.22171073.21971224 and U1804253);the Natural Science Foundation of Henan Province(No.202300410246).

摘　　要：The visible-light-induced selective oxidation of ubiquitous C–H bonds into valuable C=O bonds under aerobic conditions is one of the most attractive approaches for the construction of carbonyl-containing molecules.In this work,two transition metal-containing Nb/W mixed-addendum POMs dimers with the formula of K_(2)Na_(2)H_(5)[(Fe(H_(2)O)_(4))_(3)(P_(2)W_(15)Nb_(3)O_(62))_(2)]·24H_(2)O(POM[Fe])and K_(2)Na_(3)H_(4)[(Cr(H_(2)O)_(4))_(3)(P_(2)W_(15)Nb_(3)O_(62))_(2)]·32H_(2)O(POM[Cr])have been synthesized and characterized by various analytical and spectral techniques.POM[Fe]was proved to be an efficient photocatalyst for benzylic C–H oxidation under visible light and using oxygen as an oxidant to produce the corresponding carbonyl complex in good yields.A plausible mechanism involving superoxide radical was proposed for the catalytic reaction.POM[Fe]showed good reusability in the recycling experiments.IR spectroscopy and XRD analysis indicate that POM[Fe]can retain its integrity after catalysis.

关 键 词：POLYOXOMETALATES Mixed-addendum POMs Visible-light-induced catalysis Photocatalysis C-H bonds oxidation 

分 类 号：O621.25[理学—有机化学]