Chiral Silyl Ketene Acetals from Thioesters: Reaction with Acetals and Peroxyacetals to form 3-Alkoxy- and 3-Peroxyalkanoates
作者:Patrick H. Dussault、Tony K. Trullinger、Su Cho-Shultz
DOI:10.1016/s0040-4020(00)00894-2
日期:2000.11
Abstract The Lewis acid-mediated reaction of chiral O- and S-silyl ketene acetals (SKAs) with peroxyacetals and acetals was investigated as an approach to the asymmetric synthesis of 3-peroxy- and 3-alkoxyalkanoates. SKAs derived from chiral O-acetates fail to react with peroxyacetals and provide little diastereoselection in reactions of nonperoxidic acetals. Reaction of thioacetate SKAs with peroxyacetals
摘要 研究了路易斯酸介导的手性 O-和 S-甲硅烷基乙烯酮缩醛 (SKA) 与过氧缩醛和缩醛的反应,作为不对称合成 3-过氧和 3-烷氧基链烷酸酯的一种方法。衍生自手性 O-乙酸酯的 SKA 不能与过氧缩醛反应,并且在非过氧化缩醛反应中几乎没有非对映选择。硫代乙酸盐 SKA 与过氧缩醛的反应以良好的收率提供了 3-过氧链烷酸硫酯,但非对映选择很差。在基于樟脑磺酰胺手性助剂的甲硅烷基乙烯酮缩醛的情况下,非对映体过氧链烷酸酯很容易分离。