Remarkable Synthesis of 2-(<i>Z</i>)-6-(<i>E</i>)-4<i>H</i>-[1,4]-Thiazepin-5-ones by Zwitterionic Rhodium-Catalyzed Chemo- and Regioselective Cyclohydrocarbonylative Ring Expansion of Acetylenic Thiazoles
作者:Bernard G. Van den Hoven、Howard Alper
DOI:10.1021/ja003085c
日期:2001.2.1
Cyclohydrocarbonylative ring expansion of acetylenic thiazoles in the presence of CO, H(2), and catalytic quantities of the zwitterionic rhodium complex (eta(6)-C(6)H(5)BPh(3))(-)Rh(+)(1,5-COD) and triphenyl phosphite affords thiazepinones in 61 to 90% yields. This novel transformation of a 5- to a 7-membered heterocycle is readily applied to acetylenic thiazoles containing hydro, alkyl, alkyl halide