PhCHP(MeNCH<sub>2</sub>CH<sub>2</sub>)<sub>3</sub>N: A Novel Ylide for Quantitative <i>E </i>Selectivity in the Wittig Reaction
作者:Zhigang Wang、Guangtao Zhang、Ilia Guzei、John G. Verkade
DOI:10.1021/jo0100704
日期:2001.5.1
PhCH=P[MeNCH(2)CH(2)](3)N (1), a semi-stabilized ylide prepared from the commercially available nonionic base P[MeNCH(2)CH(2)](3)N, reacts with aldehydes to give alkenes in high yield with quantitative E selectivity. In contrast with other ylides, this E selectivity is maintained despite changes in the metal ion of the ionic base used to deprotonate 1, temperature, and solvent polarity. In conjunction
PhCH = P [MeNCH(2)CH(2)](3)N(1),由市售的非离子碱P [MeNCH(2)CH(2)](3)N制备的半稳定内立基反应与醛一起以高收率得到具有定量E选择性的烯烃。与其他烷基化物相反,尽管用于脱质子1的离子碱的金属离子,温度和溶剂极性发生了变化,但仍保持了这种E选择性。结合从1的X射线分子结构获得的结构参数,通过Wittig反应立体化学的Vedejs模型合理化了这些反应中E选择性的途径。