Short Enantioselective Total Synthesis of Tatanan A and 3-<i>epi</i>-Tatanan A Using Assembly-Line Synthesis
作者:Adam Noble、Stefan Roesner、Varinder K. Aggarwal
DOI:10.1002/anie.201609598
日期:2016.12.19
the sesquilignan natural product tatanan A and its C3 epimer are described. An assembly-line synthesis approach, using iterative lithiation-borylation reactions, was applied to install the three contiguous stereocenters with high enantio- and diastereoselectivity. One of the stereocenters was installed using a configurationally labile lithiated primary benzyl benzoate, resulting in high levels of substrate-controlled
描述了芝麻籽天然产物塔他南A及其C3差向异构体的短且高度立体选择性的总合成。流水线合成方法,使用迭代锂化-硼基化反应,被用于安装具有高对映和非对映选择性的三个连续的立体中心。使用构型不稳定的锂化的苯甲酸苄基伯酯安装了一个立体中心,导致高水平的底物控制的(非期望的)非对映选择性。但是,通过使用新型的非对映选择性Matteson同源性可以实现选择性的逆转。受阻仲苄基硼酸酯的立体特异性炔基化使得合成总共可以完成八个步骤。