作者:J.V. Sinisterra、J.M. Marinas、F. Riquelme、M.S. Arias
DOI:10.1016/s0040-4020(01)85922-6
日期:1988.1
The reactivity of several products R1R2CH-X+,1, (X=N,P,S), which can produce ylids by reaction with bases, has been tested using the activated barium hydroxide catalysts, C-200. Wittig-Horner, Wittig, Corey-Chaykovsky and Kröhnke type reactions have been analyzed. The pKa of 1, and the structure of active sites control the process. When 1 has a strong acid character, the process takes place -dissolving
已使用活化的氢氧化钡催化剂C-200测试了几种产物R 1 R 2 CH-X +,1(X = N,P,S)的反应性,这些产物可通过与碱反应生成碘。对Wittig-Horner,Wittig,Corey-Chaykovsky和Kröhnke型反应进行了分析。pKa为1,以及活性位点的结构控制着这一过程。当1具有强酸特性时,将发生过程-将固体溶解-形成均相。当1的pKa值<11时,该过程在固体的强碱位置(pKa> 11.7)进行,该位点控制了反应机理和吸附的类固醇的反应性。