Asymmetric syntheses of β-amino acids were achieved by the addition of chiral amines, R (+)- and S (-)-α-methylbenzylamines (1b and 1c), to crotonitrile, methyl crotonate (5a), l-menthyl crotonate (5b), ethyl cinnamate (5c), and methacrylonitrile, and by the addition of benzylamine (1a) to 5b, in the range of 2-19% optical purities. Among them, the configuration of the resulting β-amino acids was same as 1b and 1c used, in the reactions with crotonitrile and 5c, but was different in the cases of 5a and 5b and methacrylonitrile.
β-
氨基酸的不对称合成通过手性胺 R (+)-和 S (-)-α-甲基
苄胺 (1b 和 1c) 与克罗顿腈、甲基克罗顿酸酯 (5a)、L-薄荷基克罗顿酸酯 (5b)、乙基
肉桂酸酯 (5c) 和
甲基丙烯腈的加成实现,光学纯度范围为2%到19%。其中,所得到的β-
氨基酸的构型与用于与克罗顿腈和5c反应的1b和1c相同,但在5a、5b和
甲基丙烯腈的情况下则不同。