The enzymatic resolution of 1-(4-chlorophenyl)ethylamine by Novozym 435 to prepare a novel triazolopyrimidine herbicide
作者:Yinjun Zhang、Feifei Cheng、Hongde Yan、Jianyong Zheng、Zhao Wang
DOI:10.1002/chir.23016
日期:2018.11
donor molar ratio of 1:2.4. The conversion rate of (R,S)‐1‐(4‐chlorophenyl)ethylamine was 52%, with an enantiomeric excess of 99% towards the unreacted substrate in a reaction time of 22 hours. Finally, using optically pure (S)‐1‐(4‐chlorophenyl)ethylamine as the raw material, the chemical synthesis of (S)‐N‐(1‐(4‐chlorphenyl)ethyl)‐2‐(5,7‐dimethyl‐[1,2,4]triazolo[1,5‐a]pyrimidin‐2‐ylthio)acetamide,
(R,S)-1-(4-氯苯基)乙胺的动力学拆分是使用南极假丝酵母的商业脂肪酶完成的(Novozym 435)。研究了这种脂肪酶对(R,S)-1-(4-氯苯基)乙胺的对映选择性酰胺化反应的性能,使目标产物(S)-1-(4-氯苯基)乙胺保持未反应形式。研究了各种溶剂和酰基给体的影响,底物与酰基给体的摩尔比以及反应温度。发现最佳反应条件是在40°C下于甲基叔丁基醚中用2-四氢糠酸甲酯进行酰胺化,底物/酰基供体摩尔比为1:2.4。(R,S)-1-(4-氯苯基)乙胺的转化率为52%,在22小时的反应时间内对未反应的底物的对映体过量99%。最后,以光学纯的(S)-1-(4-氯苯基)乙胺为原料,