选择性合成1-氯-3-甲基-2-丁烯工艺条件研究

Reaction Conditions for Selective Synthesis of 1-Chloro-3-methyl-2-butylene

比较不同链长的季胺盐对异戊二烯与盐酸加成反应的异构化影响 ,筛选出新的异构化催化剂N ,N 二 (3 甲基 2 丁烯基 ) N 甲基苄基氯化铵。研究了盐酸与异戊二烯物质的量比、反应深度对产物分布的影响 ,获得最佳工艺条件 :在新催化剂存在下 ,n (酸 )∶n (异戊二烯 ) =1∶1 2～ 1 4 4 ,异戊二烯过量 4 2 % ,1 氯 3 甲基 2 丁烯的选择性达到 83 6 % ,收率 78 7% ,为选择性合成 1 氯 3 甲基 2 丁烯开辟了一条新途径。

This research tested the effect of different carbon lengths of quaternary salts on isomerization products of isoprene in the presence of HCl, and screened for two novel catalysts,N,N-di-(3-methyl-2-butenyl)-N-methyl benzylammonium chloride. The molar ratio of IP to HCl and extent of reaction on the product distribution was also investigated. Optimum reaction conditions were as follows: in the presence of the novel catalysts, with molar ratios of IP to HCl at about 1∶1.2 to 1.44, and 4.2% excess IP, the main product, 1-chloro-3-methyl-2-butylene (1,3,2-CMB),was selectively produced at 83.6%, and total 1,3,2-CMB production was 78.7%. These results provided a new approach to selective preparation of 1,3,2-CMB.