研究了以3,5-二叔丁基-4-羟基-苯甲酸和2,4-二叔丁基苯酚为原料,SOCl2为酰化试剂,一锅法合成光稳定剂3,5-二叔丁基-4-羟基-苯甲酸-2,4-二叔丁基苯基酯的工艺.通过实验考察了投料比、温度及酰化试剂用量对反应的影响,确定了较佳的工艺条件：3,5-二叔丁基-4-羟基-苯甲酸与2,4-二叔丁基苯酚的物质的量比为1∶1.1；酰化剂SOCl2与3,5-二叔丁基-4-羟基-苯甲酸的物质的量比为1.2∶1；反应温度为70℃；反应时间为11 h.还考察了结晶溶剂的种类、用量和温度对产品质量和收率的影响,得到了较佳的结晶工艺条件：V(正丁醇)/m(初产物)为1.4 mL/g；结晶温度为25℃.产品总收率可达83.0%.%The novel process preparation of the light stabilizer 2 , 4-di-tert-butylphenyl 3 , 5-di-tert-butyl-4-hydroxybenzoate by one-pot reaction was studied. The synthesis used 3,5-di-tert-butyl-4-hydroxy-benzoic acid and 2,4-di-t-butylphenol as raw material and SOCl2 as acylation reagent. The effects of raw ratio, temperature and catalyst dosage on the reaction were investigated. The optimum reaction conditions were selected as fol-lows:the molar ratio of 3 ,5-di-tert-butyl-4-hydroxy-benzoic acid to 2 ,4-di-t-butylphenol was 1∶ 1 . 1 , the mo-lar ratio of SOCl2 to 3,5-di-tert-butyl-4-hydroxy-benzoic acid was 1. 2∶ 1;the reaction temperature was 70℃;the reaction time was 11 hours. The effects of solvent kind, dosage and temperature on the product quality and crystallization yield were also investigated. The optimum conditions showed that: the ratio of 1-butanol and crude product was 1. 4 mL/g, the temperature of crystallization was 25 ℃. The total yield reached 83. 0%.
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