氯酮缩合反应绿色催化工艺的研究

Green catalytic process for condensation reaction of chlorone

在三氟甲基磺酸催化下对氯酮、新戊二醇缩合反应合成缩酮进行了研究。采用单因素实验考察了三氟甲基磺酸质量、带水剂用量、醇酮摩尔比、油浴温度等因素对反应时间及收率的影响。结果表明,随着催化剂质量的增加,反应时间缩短,收率提高;带水剂用量、醇酮摩尔比对反应时间基本无影响,对收率有一定影响;油浴温度提高有利于缩短反应时间,147.5℃时收率出现99.85%的最高值。对缩合液洗水中H^+含量进行分析表明,平均98.5%的三氟甲基磺酸进入洗水中,4次套用洗水作催化剂,反应活性没有下降,收率均在99%左右。与硫酸相比,采用三氟甲基磺酸作催化剂,反应时间缩短约70 min,且催化剂可重复使用。

Synthesis of ketal by condensation reaction between chlorone and neopentyl glycol is catalyzed by trifluoromethylsulfonic acid.The influences of the dosages of trifluoromethylsulfonic acid and water-carrying solvent,the molar ratio of neopentyl glycol to chlorone and the temperature of oil bath on the reaction time and yield are investigated by single factor experiment.The results show that with the increase of catalyst dosage,the reaction time needed shortens and the yield improves.Both the amount of water-carrying solvent and the molar ratio of neopentyl glycol to chlorone have negligible effect on the reaction time,but have some effect on the yield.The increasing oil bath temperature is beneficial to shorten the reaction time,and the yield reaches the highest value of 99.85%at 147.5℃.Analysis on H+content in the condensation reaction liquid washing water shows that about 98.5%trifluoromethylsulfonic acid on average enters the washing water,and the reactivity does not decrease even if the washing water has been reused as the catalyst for 4 times,and the yield remains about 99%.Compared with sulfuric acid,trifluoromethylsulfonic acid as catalyst shortens the reaction time by about 70 min and can be reused.