Resolution of a chiral alcohol through lipase-catalyzed transesterification of its mixed carbonate by poly(ethylene glycol) in organic media
作者:Lisa J. Whalen、Cary J. Morrow
DOI:10.1016/s0957-4166(00)00068-9
日期:2000.4
A simple approach to the resolution of chiral alcohols through a lipase-catalyzed transesterification of one enantiomer of the corresponding trifluoroethyl carbonate by a low molecular weight poly(ethylene glycol), PEG, is described. The method was demonstrated through resolution of (RS)-sec-phenethyl alcohol. The alcohol was converted to its 2,2,2-trifluoroethyl carbonate, 2, and the (R)-enantiomer
描述了一种通过低分子量聚乙二醇(PEG)的相应的三氟乙基碳酸酯的一种对映异构体的脂肪酶催化的酯交换反应来拆分手性醇的简单方法。该方法是通过(的分辨率显示出RS - )仲-苯乙基醇。将该醇转化为其2,2,2-三氟乙基碳酸酯2,并使用猪胰腺脂肪酶PPL作为催化剂,在温暖的二异丙基醚中将(R)-对映异构体与PEG选择性酯交换。通过冷却和滤出具有共价连接的(R)-醇的固体PEG,可以容易地分离出两种碳酸酯对映体。不变的水解(S碳酸盐是在稀碱水溶液中获得的,在手性转移试剂Eu(hfc)3存在下,通过NMR发现对映体过量的(S)-醇为80%。通过Eu(hfc)3的NMR ,对改性的(R)-PEG碳酸酯进行甲醇分解,得到对映体过量= 96%的(R)-仲-苯乙醇。