异戊二烯与氯化氢控制加成合成1-氯-3-甲基-2-丁烯

Controlling addition of isoprene and hydrogen chloride to isopentenyl chloride

文中应用CuCl和醋酸组成的催化剂考察了异戊二烯与HCl控制加成生成1-氯-3-甲基-2-丁烯的影响因素,确定了采用L16(45)正交试验表的试验方案,通过正交试验得到的最佳工艺条件为:醋酸0.5 mL、CuCl 0.10 g、无溶剂、10℃下进行反应,5 mL异戊二烯在该条件下反应4 h,异戊二烯的转化率和1-氯-3-甲基-2-丁烯的选择性分别为93.32%和85.83%。该反应过程可能有烯丙基化合物生成,控制该化合物的生成方向是获得1-氯-3-甲基-2-丁烯较高选择性的关键。同时也发现,反应开始时HCl的通入速度低于2 mL/min,可以减少二氯产物的生成;当异戊二烯转化率接近90%时,应停止通HCl,并用氮气置换,可以提高1-氯-3-甲基-2-丁烯的选择性。

Investigating the influence factors on controlling addition of isoprene and hydrogen chloride to isopentenyl chloride with cuprous chloride （CuC1） and acetic acid as catalyst. The methods according to the rules of orthogonal test table L16 （45） were chosen to determine the appropriate values of five factors, including the sort of solvent, reaction temperature, the sort of promoter, the type of catalyst and the concentration of catalyst. The test result shows that under the optimal processing condition of acetic acid 0.5 mL, CuC1 0.10 g, without solvent, reaction temperature 10 ℃, the conversation of 5 mL isoprene and the selectivity to isopentenyl chloride are 93.32% and 85.83% respectively after the reaction is kept for 4 h. The reaction may generate allylic compounds and the generated direction of the compound plays a key role in controlling the selectivity of isopentenyl chloride. Keeping the catalyst as pale yellow with lower adding speed of hydrogen chloride not exceeding 2 mL/min at the beginning of reaction can protect to obtain high selectivity of the target product. When isoprene conversion is close to 90%, adding of hydrogen chloride should be stopped, gas. These methods can enhance the selectivity and unreacted hydrogen chloride should be replaced by nitrogen of isopentenyl chloride