Two novel chiral Brønsted acids 3b and 3c were prepared without involving the complexity of Suzuki coupling.Catalyst 3c bearing two additional hydroxyl groups at 3 and 3'positions of axially chiral 1,1-binaph...Two novel chiral Brønsted acids 3b and 3c were prepared without involving the complexity of Suzuki coupling.Catalyst 3c bearing two additional hydroxyl groups at 3 and 3'positions of axially chiral 1,1-binaphthalene-2,2'-diol phosphoric acid was applied in a model Mannich reaction to affordβ-amino ester in high yield(92%)and enantiomeric excess(91%)at low reacting temperature of−40℃.In addition,thoseβ-amino ester derivatives with high yields and excellent enatioselectivities were obtained in the presence of catalyst 3c under the above condition.展开更多
基金the Natural Science Foundations of Guizhou Province[Nos.KY(2014)317 and KY(2011)232]the Educational Ministry Foundation of Guizhou Province[No.KY(2012)018].
文摘Two novel chiral Brønsted acids 3b and 3c were prepared without involving the complexity of Suzuki coupling.Catalyst 3c bearing two additional hydroxyl groups at 3 and 3'positions of axially chiral 1,1-binaphthalene-2,2'-diol phosphoric acid was applied in a model Mannich reaction to affordβ-amino ester in high yield(92%)and enantiomeric excess(91%)at low reacting temperature of−40℃.In addition,thoseβ-amino ester derivatives with high yields and excellent enatioselectivities were obtained in the presence of catalyst 3c under the above condition.