(rac-1a) and 15-crown-5 diol (rac-1c) was achieved by lipase-catalyzed acetylation. The enantiomeric excess of the chiralcrown diols (95% ee and 82% ee) was determined by 1H NMR spectroscopy, using (R)-(+)-1-(1-naphthyl)ethylammonium hydrochloride as a shift reagent. The C2-symmetric chiral 15-crown-5 diol (>95% ee) was also obtained by kinetic resolution of the racemic diacetate (rac-2c) using lipase-catalyzed
C 2对称的18冠-6二醇(rac - 1a)和15冠5二醇(rac - 1c)外消旋混合物的动力学拆分通过脂肪酶催化的乙酰化作用实现。使用(R)-(+)-1-(1-萘基)乙基铵盐酸盐作为位移试剂,通过1 H NMR光谱法测定手性冠二醇的对映体过量(95%ee和82%ee)。通过使用脂肪酶催化的溶剂分解动力学拆分外消旋二乙酸酯(rac - 2c),也可以获得C 2对称的手性15冠-5二醇(> 95%ee)。