Asymmetric Synthesis of Protected 2-Keto-1,3-diol and 1,2,3-Triol Building Blocks Bearing a Quaternary Stereogenic Center
作者:Dieter Enders、Anja Nühring、Jan Runsink、Gerhard Raabe
DOI:10.1055/s-2001-15236
日期:——
The asymmetric synthesis of protected 2-keto-1,3-diols 5 and 1,2,3-triols 6 bearing a quaternary stereogenic center starting from 2,2-dimethyl-1,3-dioxan-5-one (1) is described. The stereogenic centers are generated by sequential α-alkylation of 1 using the SAMP/RAMP hydrazone method and stereoselective reduction of ketones 5 with l-selectride. The products are obtained in good yields and high diastereomeric and enantiomeric excesses.
描述了从2,2-二甲基-1,3-二氧戊酮(1)出发的保护型2-酮-1,3-二醇5和1,2,3-三醇6的不对称合成,这些化合物具有一个四元立体中心。通过使用SAMP/RAMP肼酮法对1进行顺序α-烷基化以及对酮5进行立体选择性还原,产生了立体中心。所得到的产品具有良好的产率,以及高的二醇和对映体过量。