Interaction of alkoxides XVIII. Utilitization of the complex base from alkyllithium and potassium alkoxides in the dimetallation of phenol, thiophenol, o-, m- and p-cresol
作者:H. Andringa、H.D. Verkruijsse、L. Brandsma、L. Lochmann
DOI:10.1016/0022-328x(90)85160-z
日期:1990.9
Successful O- and ortho-ring metallation of phenol and side chain metallation in o-cresol has been achieved by use of a mixture of two molar equivalents of n-butyllithium, one molar equivalent of potassium t-butoxide, and two molar equivalents of N,N,N′,N′-tetramethylethylene diamine in hexane. Poor results were obtained with m-cresol, thiophenol and p-cresol. m-Cresol was effectively dimetallated with
通过使用两个摩尔当量的正丁基锂,一个摩尔当量的叔丁醇钾和两个摩尔当量的N的混合物,可以成功地实现苯酚的O-和邻环金属环化以及邻甲酚中的侧链金属化。,N,N ',N'-四甲基乙二胺在己烷中。差的结果用获得米甲酚,苯硫酚和p甲酚。用两个摩尔当量的t BuOK和两个摩尔当量的n的混合物有效地将m- Cresol进行双金属化BuLi·TMEDA。还研究了另一种基于2-乙基己基锂(EhexLi)和烷醇钾的复合碱的有效性,特别是在所用烷醇的浓度和结构方面。使用EhexLi的复杂碱和3当量的3-甲基-3-五氧化钾钾,即使在没有TMEDA的情况下,苯酚也能成功地双金属化。因此,已经证实,与先前使用的复合碱相比,包含更高浓度的更支化的醇钾的复合碱的反应性增强。