经钛杂环合成立体选择的三取代乙烯

Stereoselective Synthesis of Trisubstituted Alkenes via Titanocycles

用连续法改进了Masai-Rausch合成钛杂环及烯烃的反应,提高了烯烃收率及Cp_(2)TiCl_(2)回收率,以不对称炔烃为底物合成了十二组烯烃,其中两组为单一构型的烯,其余为异构体混合物,除常规分析外,还分离分析了钛杂环中间物、分析核磁谱等,确定了烯烃的结构及异构体相对量。

By previously reported modified Masai-Rausch method for synthesizing titano-Cycles, followed by add hydrolysis, trisubstituted alkenes were synthesized, yields obtained were higher than that reported in literature.Starting from unsymmetrical alkyne substrates, twelve different types of substituted alkenes were synthesized, among which only two were found of single component, others were of isomer mixtures.Besides conventional analytical methods, NMR spectral analysis of titanocycle intermedlates and the products was used to identify the isomeric structures as well as their relative contents.