A facile synthetic route to 2-trifluoromethyl-substituted polyfunctionalized chromenes and chromones
作者:Lele Wen、Honghai Zhang、Hao Lin、Qilong Shen、Long Lu
DOI:10.1016/j.jfluchem.2011.10.011
日期:2012.1
A method for the preparation of methyl 4-hydroxy-2-(trifluoromethyl)-4H-chromenes-3-carboxylate derivatives 3a–j from readily available trifluoromethylated building block methyl (Z)-2-bromo-4,4,4-trifluoro-2-butenoate 1 was described. Treatment of 3a–j with Sarrett reagent in CH2Cl2 generated methyl 4-oxo-2-(trifluoromethyl)-chromene-3-carboxylate derivatives 4a–h with moderate to good yields, which
A simple and convenient synthesis of 2-(perfluoroalkyl)-4H-chromenes from salicyl N-tosylimines or salicylaldehydes and methyl 2-perfluoroalkynoates
作者:Lei Lu、Jiamei Wei、Jie Chen、Jiaping Zhang、Hongmei Deng、Min Shao、Hui Zhang、Weiguo Cao
DOI:10.1016/j.tet.2009.09.030
日期:2009.11
Et3N-catalyzed reactions of salicyl N-tosylimines or salicylaldehydes with methyl 2-perfluoroalkynoates proceed smoothly at room temperature in dichloromethane (DCM) or dimethyl sulfoxide (DMSO) to give the corresponding fluorinated chromenes in good to excellent yields with high regioselectivity.