一种1,2-二溴-1,1-二氯-2,2-二氟乙烷的制备新方法

A New Preparation Method of 1,2-Dibromo-1,1-dichloro-2,2-dichloroethane

以偏氟乙烯为原料,经光氯化、脱氯化氢、溴化加成3步反应合成1,2-二溴-1,1-二氯-2,2-二氟乙烷,试验了各种因素对反应的影响。光氯化反应时温度低有利于2,2-二氟-1,1,2-三氯乙烷选择性的提高,相转移催化剂四丁基溴化铵能加快反应脱氯化氢的速率,溴加成的合适温度为15～20℃。结果表明此合成路线是可行的。

1,2-Dibromo-1,1-dichloro-2,2-dichloroethane is synthesized through 3 steps of photo chlorination,dehydrochlorination and bromination addition from vinylidene fluoride. Low photo chlorination temperature is helpful to raise the selectivity of 2,2-dichloro-1,1,2-trichloroethane.Phase transfer catalyst tetrabutyl amonium bromide can quicken the rate of dehydrochlorination reaction, proper bromine addition temperature is 15～20 ℃. Results show this synthesis method is feasible.