Formal Synthesis of 3-Deoxy-<scp>d</scp>-manno-2-Octulosonic Acid (KDO) via a Highly Double-Stereoselective Hetero Diels−Alder Reaction Directed by a (Salen)Co<sup>II</sup> Catalyst and Chiral Diene
作者:Yun-Jin Hu、Xiao-Dong Huang、Zhu-Jun Yao、Yu-Lin Wu
DOI:10.1021/jo971186w
日期:1998.4.1
This paper presents a formal total synthesis of 3-deoxy-D-manno-2-octulosonic acid (KDO) based on a highly double-stereoselective hetero Diels-Alder reaction between an electron-rich diene and ethyl glyoxylate catalyzed by (Salen)Co(II) complex, a new catalyst for Diels-Alder reactions. A facial specific hydroboration followed by oxidative workup leads to a diol system with the trans-diequatorial arrangement
本文基于(Salen)Co催化的富电子二烯与乙醛酸乙酯之间的高度双立体选择性杂Diels-Alder反应,提出了3-脱氧-D-甘露糖-2-辛磺酸的正式全合成(II)络合物,是Diels-Alder反应的新催化剂。面部特定的硼氢化随后进行氧化处理会导致二醇系统在C-4和C-5处具有羟基的透-透水合安排。将C-5羟基的构型转化为12,然后缩酮形成,得到所需的目标二异亚丙基-2-脱氧-KDO甲基酯(18),可以根据文献方法将其转化为KDO。