离子液体相转移催化制备2,3,5-三氯吡啶

目的研究离子液体1-丁基-3-甲基咪唑六氟磷酸盐作为相转移催化剂，以五氯吡啶（PCP）为原料合成2，3，5-三氯吡啶的适宜条件。方法利用单因素实验法分析相转移催化剂、反应温度、反应时间、NaOH浓度、nZn：nPCC，等因素对产物收率的影响。结果制备2，3，5-三氯吡啶的适宜实验条件：相转移催化剂用量3mmol，反应温度40℃，反应时间5h，NaOH浓度7mol／L，nzn：nPCP=3．0：1。此条件下，产物收率可达75％以上。结论利用离子液体替代传统有机溶剂作为相转移催化剂合成新工艺，具有反应时间短，锌粉用量少，反应温度温和等特点，可达到绿色生产之目的。

Synthesis of 2, 3, 5-trichioropyridine by ionic liquid as phase transfer catalyst

Aim To study the favorable synthesis conditions of 2, 3, 5-trichloropyridine been syn- thesized with 1-butyl-3-methylimidazolium hexafluorophosphate （BMIMPF6） as phase transfer cata- lyst using pentachloropyridine（PCP）. Methods Single factor methods is used to investigate phase transfer catalyst, reaction temperature, reaction time, concentration of sodium hydroxyl , the mole ratio of zinc to pentachloropyridine on the yield of 2, 3, 5-trichloropyridine. Results Favorable syn- thesis conditions of this product are as follow： dosage of catalyst is 3 mmol, reaction temperature is 40 ℃, reaction time is 5 h, concentration of NaOH was 7 mol/L , the mole ratio of zinc to PCP is 3.0 to 1. Under the conditions, The yield of 2, 3, 5-trichloropyridine was above 75%. Conclusion The re- suits showed that reaction time was shortened and mole ratio of zinc to PCP reduced and reaction tem- perature lower with 1-butyl-3-methylimidazolium hexafluorophosphate （BMIMPF6） as phase transfer catalyst.