光学活性螺-环丙烷双内酯化合物的合成

描述了5-(l-孟氧基)-3-溴-2(5H)-呋喃酮新手性试剂1与氮亲核试剂发生的串联不对称双Michael加成/分子内亲核取代反应,一举生成4个新手性中心。报道了含有叔胺官能团的螺-环丙烷双内酯化合物4a-4d的合成方法以及结构测定。

Synthesis of functionalized spiro-cyclopropane bis-lactones containing multiple chiral centers

In this paper, the unusual spiro-cyclopropane bis-lactones containing four stereogenic centers 4a-4d were obtained in 25%-48% yields with d.e.≥98% via tandem double Michael addition/internal nucleophilic substitution of the novel chiral synthon, 5-l-menthyloxy- 3-bromo-2-(5H)-furanone 1, with nitrogen nucleophiles under mild conditions. The structure and configuration were established on the basis of their analytical and spectroscopic ([α]~D^2^0, UV, IR, ^1H NMR, ^1^3C NMR, MS and X-ray crystallographic) data. These results provide a valuable synthetic route to some complex molecules containing spiro-cyclopropane skeleton with multiple chiral centers.