【摘要】 以2,4-二羟基苯甲酸和间苯二酚为原料,无水氯化锌与三氯氧磷为复合催化剂,环丁砜为溶剂,通过Friedel-Crafts反应合成了紫外线吸收剂2,2′,4,4′-四羟基二苯甲酮,同时研究了催化剂、原料配比、温度、时间及溶剂用量对该C-酰化反应的影响,得到较好的工艺条件为:原料n(酚)∶n(酸)为1 4∶1 0,复合催化剂m(POCl3+ZnCl2)∶m(原料)为1 4∶1 0,其中m(POCl3)∶m(ZnCl2)为1 33∶1,溶剂m(环丁砜)∶m(原料)为0 6∶1 0,70℃下反应2 2h,产品收率可达87%以上。更多还原

【Abstract】 The ultraviolet absorbent 2,2′,4,4′-tetrahydroxybenzophenone was prepared from 2,4-dihydroxy benzoic acid and resorcin in solvent medium sulfolane using anhydrous ZnCl₂ and POCl₃ as blend catalyst.The effects of catalyst,ratio of raw material,temperature,time and amount of solvent on this reaction were studied.The optimum conditions are as follows:n（phenol）∶n（acid）=1.4∶1,m（POCl₃+ZnCl₂）∶m（material）=1.4∶1,m（POCl₃）∶m（ZnCl₂）=1.33∶1,m（solvent）∶m（reactants）=0.6∶1,at 70 ℃ for 2.2 h.The yield of product was higher than 87.0 %.更多还原