Direct benzylation reactions from benzyl halides enabled by transition-metal-free photocatalysis  

作　　者：Panjie Xiang Kai Sun Shuang Wang Xiaolan Chen Lingbo Qu Bing Yu 

机构地区：[1]Green Catalysis Center,College of Chemistry,Zhengzhou University,Zhengzhou 450001,China [2]Zhengzhou Tobacco Research Institute of CNTC,Zhengzhou 450001,China

出　　处：《Chinese Chemical Letters》2022年第12期5074-5079,共6页中国化学快报（英文版）

基　　金：support from the National Natural Science Foundation of China(Nos.21971224,22071222,22171249);111 Project(No.D20003);the Key Research Projects of Universities in Henan Province(No.21A150053);the Natural Science Foundation of Henan Province(No.202300410375);China Postdoctoral Science Foundation(No.2021M692906);Henan Postdoctoral Foundation(No.202003014).

摘　　要：An SN2-based photochemical strategy using dithiocarbamate anion as catalyst was developed for the activation of benzyl halides,which are extremely challenging to be applied as radical precursors in visible light photocatalysis.With this transition-metal-free and oxidant-free protocol,the benzylation(or cyanomethylation)of various heterocycles including quinoxalin-2(1H)-ones,coumarin,2-phenyl-2H-indazole,1-methyl-5-phenylpyrazin-2(1H)-one,1-(fluoromethyl)cinnolin-4(1H)-one,and 2,4-dibenzyl-1,2,4-triazine-3,5(2H,4H)-dione could be realized(46 examples,up to 98%yield).Importantly,some biologically relevant 3-benzylquinoxalin-2(1H)-ones were also be synthesized under mild conditions.

关 键 词：BENZYLATION PHOTOCATALYSIS Transition-metal-free Radical reaction N-Heterocyclics 

分 类 号：O626[理学—有机化学] O643.36[理学—化学]