Phosphine-phosphonium ylides as ligands in palladium-catalysed C2-H arylation of benzoxazoles  

作　　者：Zhenyu Yao Xing Lin Remi Chauvin Lianhui Wang Emmanuel Gras Xiuling Cui 

机构地区：[1]Engineering Research Centre of Molecular Medicine of Ministry of Education,Key Laboratory of Fujian Molecular Medicine,Key Laboratory of Precision Medicine and Molecular Diagnosis of Fujian Universities,Key Laboratory of Xiamen Marine and Gene Drugs,School of Biomedical Sciences,Huaqiao University,Xiamen 361021,China [2]Laboratory of Coordination Chemistry(LCC),CNRS&Universite'de Toulouse(UPS,INP),Toulouse 31077 Cedex 4,France

出　　处：《Chinese Chemical Letters》2020年第12期3250-3254,共5页中国化学快报（英文版）

基　　金：the financial support from the National Natural Science Foundation of China(Nos.21572072 and 21602064);111 Project(No.BC2018061)。

摘　　要：As balanced electron-rich P,C-chelating ligands,phosphine-phosphonium-ylides are considered for their ability to in situ promote palladium-catalysed direct C(sp^2)—H arylation.Using methyl phosphonium salts of 2,2’-bis(diphenylphosphino)-1,1’-binaphtyl("methyl-BINAPIUM")as ylide precursors under optimized reaction conditions,arylation of benzoxazole was found to proceed in moderate to high yield to give functional 2-aryl benzoxazoles.A strong anion effect of the non-salt free ylide was evidenced(TfO^->I^->PF6^-≈salt-free).This first example of phosphonium ylides as ligands in catalytic C-H activation extends the prospect of their general implementation in homogeneous transition metal catalysis.

关 键 词：ELECTRON-RICH Ligands Phosphine-phosphonium-ylides Benzixazole C-H activation 

分 类 号：O641.4[理学—物理化学] O621.251[理学—化学]