介绍了我们小组最近有关原位生成的烯丙基磷叶立德与醛的化学反应性研究结果.在化学计量叔膦作用下,烯丙基碳酸酯或联烯酸酯经原位生成的烯丙基磷叶立德活性中间体,与醛发生高度立体选择性的三组分Wittig烯化反应和vinylogousWittig烯化反应,该类反应为合成多取代1,3-二烯衍生物提供了简单、高效的新方法;在催化量叔膦作用下,γ-甲基联烯酸酯经烯丙基磷叶立德关键中间体与醛发生多个瞵催化的环化反应,为五元、六元含氧杂环化合物的合成提供了原子经济性的方法.通过氘代实验和核磁跟踪等方法,对上述反应机理进行了初步探索.
This account primarily summarizes our recent work on the reactivity of in situ generated allylic phosphorus ylides with aldehydes. Under the mediation of stoichiometric tertiary phosphines, allylic carbonates or allenoates readily undergo highly stereoselective three-component Wittig and vinylogous Wittig olefination reactions through in situ generated allylic phosphorus ylides. These reactions constitute simple and efficient synthetic methods for polysubstituted 1,3-riches. Under the catalysis of tertiary phosphines, y-methyl allenoates chemoselectively undertake several annulations with aldehydes via a key intermediate of allylic phosphorus ylide, providing atom economical synthesis of 5- and 6-membered oxygen heterocycles. By experimental approaches such as deuterium-labeling and NMR monitoring, mechanisms of the above mentioned reactions have also been investigated.