有机酸催化甘油法制备二氯丙醇的反应研究

Study on the Process of Producing Dichloropropanol from Glycerol Catalysted by Organic Acid

本文对有机酸催化甘油法制备环氧氯丙烷中间体二氯丙醇的反应过程进行研究。通过考察反应产物随时间的变化,探讨了离去基团和催化剂对反应性能的影响,认为该反应主要按双分子亲核取代机理进行,选择酸性强的有机酸做催化剂,可使羟基转变为离去能力更大的基团以促进反应。碳链长度C4～C8的二元酸催化性和选择性较佳,采用己二酸为催化剂时,二氯丙醇产量可至85%。

With organic acids as the catalysts, glycerol was subjected to a reaction with hydrogen chloride to prepare dichloropropanol which wass the intermediate product of epichlorohydrin. Variation of the main resultants of the reaction over time were studied. And the influences of leaving group and catalysts on the reactivity were discussed. The experimental result shows that it reacts according to mechanism of bimolecular nucleophilic substitution. In the absence of strong organic diacid, oxhydryl changes to another leaving group which has stronger leaving capability than itself. The acid preferably contains more than 4 but less than 8 carbon atoms, especially adipic acid is preferred. The yield of dichloropropanol exceeds 85%.