An efficient route to 4-halophosphaisocoumarins via CuX2-mediated direct halocyclization of 2-(1-alkynyl)phenylphosphonic acid diesters.
A series of 4-halophosphaisocoumarins were synthesized via CuX2 (X = Br, Cl) -mediated direct halocyclization of 2-(1-alkynyl)phenylphosphonic acid diesters in dichloroethane with the addition of n-Bu4NX or/and AgI in good to excellent yields. This reaction provides an efficient route to 4-halophosphaisocoumarins and represents the first example of bromo- and chlorocyclization of unsaturated phosphonic acid diesters.
Peng
Ai-Yun
AY
School of Chemistry & Chemical Engineering, Sun Yat-sen University, 135 Xingangxi Lu, Guangzhou, 510275, China. cespay@mail.sysu.edu.cn
Hao
Fei
F
Li
Baojian
B
Wang
Zheng
Z
Du
Yidan
Y