Department of Chemistry, National Tsing Hua University, Hsinchu 300, Taiwan.
Org Lett. 2010 Nov 19;12(22):5338-41. doi: 10.1021/ol102383g. Epub 2010 Oct 28.
The syntheses of both enantiomers of cyclobutanes B and ent-B are achieved through heteroatom-directed conjugate addition (HADCA) of nucleophiles to the epoxyvinylsulfone-substituted carbohydrates A and ent-A, which provided carbanions that intramolecularly attacked the epoxide with concomitant formation of the cyclobutane ring.
通过亲核试剂对带有环氧乙烯砜取代基的碳水化合物 A 和 ent-A 的杂原子导向共轭加成(HADCA),实现了环丁烷 B 和 ent-B 的两种对映异构体的合成,这提供了碳负离子,其分子内攻击环氧化物并同时形成环丁烷环。