Cp2TiCl2-Catalyzed Grignard exchange reactions with acetylenes. A convenient method for preparation of E-alkenyl Grignard reagents
作者:Fumie Sato、Hiroaki Ishikawa、Masao Sato
DOI:10.1016/0040-4039(81)80047-0
日期:1981.1
E-alkenyl Grignard reagents selectively and in almost quantitative yields. The regiochemistry of this hydromagnesation reaction is high for alkylarylacetylenes and silylacetylenes giving E-ArC(MgBr)CHR from alkylarylacetylenes, E-ArC(MgBr)CH(SiMe3) from arylsilylacetylenes, and ECHRC(MgBr)(SiMe3) from alkylsilylacetylenes, respectively. Thanks to the high reactivity of the Grignard reagent, the present
在醚中催化量的Cp 2 TiCl 2的存在下,二取代的乙炔与异丁基卤化镁反应,可选择性地以几乎定量的产率得到E-烯基格利雅试剂。对于烷基芳基乙炔和甲硅烷基乙炔而言,这种加氢镁化反应的区域化学反应很高,烷基芳基乙炔可产生E-ArC(MgBr)CHR,芳基甲硅烷基乙炔可产生E-ArC(MgBr)CH(SiMe 3),ECHRC(MgBr)(SiMe 3)分别来自烷基甲硅烷基乙炔。由于格氏试剂的高反应性,本反应为制备三取代的烯烃提供了新颖,选择性和操作简单的途径。