gem-Difluoroallyllithium: Preparation by the transmetalation procedure and some reactions
作者:Dietmar Seyferth、Karl R. Wursthorn
DOI:10.1016/s0022-328x(00)83935-2
日期:1979.12
3,3-Difluoroallyltrimethyltin has been prepared by the reaction of β-trimethylstannylethylidenetriphenylphosphorane with chlorodifluoromethane. This tin compound reacts with n-butyllithium in tetrahydrofuran at -95°C to generate gem-difluoroallyllithium. The latter, however, is not stable in solution at that temperature. If generated in situ in the presence of a triorganochlorosilane, products of the
3,3-二氟烯丙基三甲基锡是通过β-三甲基锡烷基亚乙基三苯基膦与氯二氟甲烷反应制得的。该锡化合物与四丁基呋喃中的正丁基锂在-95°C下反应生成宝石-二氟烯丙基锂。然而,后者在该温度下在溶液中不稳定。如果在三有机氯硅烷的存在下原位产生,则以高收率获得R 3 SiCF 2 CH = CH 2类型的产物。通过交替增量加入的方法,将3-戊酮的C = O键加成得到(C 2 H 5)2 C(OH)CF 2 CH = CH 2。