2-氯-5-氯甲基吡啶生产工艺的改进  

Innovation of technics for producing 2-chloro-5-chloromethylpyridine

作　　者：李明[1] 石晓华[1] 周彩荣[1] 

机构地区：[1]郑州大学化工与能源学院,河南郑州450001

出　　处：《精细与专用化学品》2010年第1期47-49,共3页Fine and Specialty Chemicals

摘　　要：2-氯-5-氯甲基吡啶是吡虫啉等农药的关键中间体。工业生产中采用直接环合法生产存在甲苯用量大、不易回收、精馏过程产品损失等问题。通过优化环合反应,用结晶法提纯产品,使环合反应收率达到77.91%,结晶提纯率大于83%,产品纯度达到90%以上,能够满足工业生产要求,且减少了甲苯的使用和精馏废渣的排放。2-Chloro 5 chloromethylpyridine is the crucial intermediate of pesticides such as Imidacloprid, which is produced through the direct cyclization of 2-chloro-2-chloromethyl-4- cyanobutyraldehyde and phosphorus oxychloride. This route is widely used in industries, but toluene used as solvent lead the difficulty of recycling, and the product decomposed in distillation. So the conditions of cyclization were optimized and the crystallization was used to purify the product. Under the improved conditions, the yield of cyclization reached to 77.91 percent, and the purification yield was above 83 percent with 90 percent purity. That meets the need of industry, which reduces the using of toluene and exhaust of waste residue in distillation.

关 键 词：2-氯-5-氯甲基吡啶 结晶 环合 

分 类 号：TQ253.2[化学工程—有机化工] TQ225.52