Highly Stereoselective Glycosylation Reactions of Furanoside Derivatives via Rhenium (V) Catalysis
作者:Emanuele Casali、Sirwan T. Othman、Ahmed A. Dezaye、Debora Chiodi、Alessio Porta、Giuseppe Zanoni
DOI:10.1021/acs.joc.1c00706
日期:2021.6.4
approach for the formation of anomeric carbon-functionalized furanoside systems was accomplished through the employment of an oxo-rhenium catalyst. The transformation boasts a broad range of nucleophiles including allylsilanes, enol ethers, and aromatics in addition to sulfur, nitrogen, and hydride donors, able to react with an oxocarbenium ion intermediate derived from furanosidic structures. The excellent
通过使用氧代铼催化剂,实现了一种形成异头碳官能化呋喃糖苷系统的新方法。该转变拥有广泛的亲核试剂,包括烯丙基硅烷、烯醇醚和芳烃以及硫、氮和氢化物供体,能够与源自呋喃糖苷结构的氧代碳鎓离子中间体反应。观察到的优异立体选择性遵循 Woerpel 模型,最终提供 1,3-顺式-1,4-反式系统。在富电子芳香亲核试剂的情况下,平衡发生在异头中心,选择性形成 1,3-反式-1,4-顺式系统。这个异常结果通过密度泛函理论计算得到了合理化。不同的氧代碳鎓离子,例如衍生自二氢异苯并呋喃、吡咯烷和恶唑烷杂环的那些,也可用作氧代-Re 介导的烯丙基化反应的底物。