Highly effective and enantioselective Michael addition of 4-hydroxycoumarin to α,β-unsaturated ketones promoted by simple chiral primary amine thiourea bifunctional catalysts
作者:Ren-Qiang Mei、Xiao-Ying Xu、Yan-Chun Li、Ji-Ya Fu、Qing-Chun Huang、Li-Xin Wang
DOI:10.1016/j.tetlet.2011.01.054
日期:2011.4
Highly asymmetric Michael addition of 4-hydroxycoumarin to α,β-unsaturatedketones promoted by chiral primary amine thiourea bifunctional catalysts was developed and a series of Michael adducts were obtained in excellent yields (up to 97%) and enantioselectivities (up to 95% ee). Optically pure S-warfarin was easily obtained in 99% ee after single recrystallization.
Highly enantioselective synthesis of Warfarin and its analogs catalysed by primary amine–phosphinamide bifunctional catalysts
作者:Juan Dong、Da-Ming Du
DOI:10.1039/c2ob26334c
日期:——
An efficient enantioselective Michael addition of 4-hydroxycoumarin to α,β-unsaturated ketones catalysed by primary amine–phosphinamide bifunctionalcatalysts has been developed. This reaction afforded Warfarin and its analogs in moderate to excellent yields (up to 99%) and good to excellent enantioselectivities (up to 99% ee).