抗氧剂168的连续流高效制备

Highly Efficient Synthesis of Antioxidant 168 in Continuous Flow

摘要:

本文提出了一种连续流合成抗氧剂168的新工艺方法，该法具有反应停留时间短、操作简单、安全性能高等优点。以2,4-二叔丁基苯酚和三氯化磷为原料，通过酯化反应连续流合成抗氧剂168，考察了反应溶剂、缚酸剂种类及用量、反应温度、反应停留时间对抗氧剂168收率的影响，并通过熔点、GC、1H NMR、13C NMR和HRMS对合成产物进行了表征。结果表明，最佳工艺条件为：n(2,4-二叔丁基苯酚):n(三氯化磷):n(三乙胺)=3.0:1.0:3.3，甲苯为溶剂，反应温度为75℃，反应停留时间为240s，经后处理，精制产物收率可达90%，纯度大于99.9%。

Abstract:

A novel method for the synthesis of antioxidant 168 has been developed in continuous flow, which has the advantages of short reaction residence time, simple operation and high safety performance. Antioxidant 168 was synthesized by esterification of 2,4-ditert-butylphenol and phosphorus trichloride in continuous flow, and the effects of reaction solvent, type and dosage of acid-binding agent, reaction temperature and reaction residence time on the yield of antioxidant 168 were investigated. The desired product was characterized by melting point, GC, 1H NMR, 13C NMR and HRMS. The results showed the optimum conditions were determined as follows: the molar ratio of 2,4-ditert-butylphenol, phosphorus trichloride and triethylamine was 3.0:1.0:3.3, the reaction temperature was 75℃, the reaction residence time was 240s. The yield of antioxidant 168 was 90%under the optimum conditions, and the purity exceeded 99%.