Efficient Lipase-Catalyzed Enantioselective Desymmetrization of Prochiral 2,2-Disubstituted 1,3-Propanediols and Meso 1,2-Diols Using 1-Ethoxyvinyl 2-Furoate
作者:Shuji Akai、Tadaatsu Naka、Tetsuya Fujita、Yasushi Takebe、Toshiaki Tsujino、Yasuyuki Kita
DOI:10.1021/jo010587f
日期:2002.1.1
desymmetrization of prochiral 2,2-disubstituted 1,3-propanediols was developed using 1-ethoxyvinyl 2-furoate 1b, for which the well-known method using vinyl or isopropenyl acetate has had limited success due to low reactivity and easy racemization of the products through acyl group migration. The reagent 1b is highly reactive and converts various prochiral 1,3-diols to the monoesters having a chiral quaternary
使用1-乙氧基乙烯基2-糠酸酯1b,开发了一种有效的脂肪酶催化的手性2,2-二取代的1,3-丙二醇的脱对称化,由于其低反应性和低粘度,众所周知的使用乙烯基乙酸或异丙烯基乙酸酯的方法获得的成功有限。通过酰基迁移使产品易于消旋。试剂1b是高反应性的,并且将各种手性的1,3-二醇转化为具有手性季碳中心且ee为82-99%的单酯。这些产物在酸性条件下对外消旋作用是稳定的,它们的呋喃酰基与氧化条件相容。延长反应时间导致单酯的动力学拆分,从而导致其光学纯度的提高。内消旋顺式1,2-环烷二醇的相似脱对称得到单酯,其ee为82-97%,没有消旋化。