作者:Michael G. N. Russell、Raymond Baker、Richard G. Ball、Steven R. Thomas、Nancy N. Tsou、José L. Castro
DOI:10.1039/a909816j
日期:——
segment of ephedradine C has been achieved. Key steps include a chiral oxazolidinone-mediated aldol reaction to form a β-hydroxy ester, followed by a novel debenzylation and concomitant intramolecular cyclisation with iodotrimethylsilane. An asymmetric Michael reaction with a homochiral lithium amide was used to form the third and final chiral centre. The absolute stereochemistry of these three centres was
麻黄碱C的二氢苯并呋喃链段的不对称合成已经实现。关键步骤包括手性恶唑烷酮介导的羟醛反应形成β-羟基酯,然后进行新的脱苄基作用并伴随分子内 环化 和 碘三甲基硅烷。与同手性锂酰胺的不对称迈克尔反应用于形成第三个也是最后一个手性中心。通过X射线晶体结构测定证实了这三个中心的绝对立体化学。