Direct and enantiospecific ortho-benzylation of phenols by the Mitsunobu reaction
作者:Shoji Fukumoto、Shigeha Fukushi、Shinji Terao、Mitsuru Shiraishi
DOI:10.1039/p19960001021
日期:——
ortho-Substituted phenol derivatives with high optical purity have been obtained directly by Mitsunobu reaction between an appropriate phenol and an optically active benzyl alcohol. In this reaction, the chemical yield was well balanced with the optical purity of the ortho-substituted compound when 5 equiv. of phenol was allowed to react with 1 equiv. of alcohol in a solvent such as dichloroethane or toluene. In addition, it was confirmed by an X-ray analysis of the product that stereochemical inversion of the asymmetric centre took place in this reaction, as well as the usual Mitsunobu reaction. This reaction is useful in the preparation of optically active phenol derivatives possessing a diarylmethane moiety.
通过米津信反应,直接从适当的酚和光学活性的苄醇中获得了具有高光学纯度的邻位取代酚衍生物。在这一反应中,当用5当量的酚与1当量的醇在二氯乙烷或甲苯等溶剂中反应时,化学产率与邻位取代化合物的光学纯度之间保持了良好的平衡。此外,通过产品的X射线分析确认,在这一反应中,不对称中心发生了立体化学反转,这与常规的米津信反应一致。该反应在制备具有二芳基甲烷结构的光学活性酚衍生物方面非常有用。