UV-327合成新工艺的研究

Study on a new process for synthesis of ultraviolet absorber 327

报道了一种用葡萄糖和锌粉为还原剂,以4-氯-2-硝基苯胺为原料,经重氮、偶合和二次还原合成紫外线吸试剂(UV)327的合成新工艺.同时考察了硫酸、2,4-二叔丁基苯酚和不同还原剂组合对反应的影响.结果表明,4-氯-2-硝基苯胺(a)在硫酸(b)和亚硝酸钠的作用下进行重氮化,与2,4-二叔丁基苯酚(c)偶合生成2-硝基-4-氯-2′-羟基-3′,5′-二叔丁基偶氮苯的较佳条件是:(a)∶(b)∶(c)=1∶5.75:1.1(mol),采用葡萄糖和锌粉组合还原2-硝基-4-氯-2′-羟基-3′,5′-二叔丁基偶氮苯合成UV-327,效果比Na2S和锌粉组合还原好.并通过HPLC,1H-NMR,IR和紫外光谱对目标产品进行了分析.该方法以4-氯-2-硝基苯胺计,总收率达83.2%,目标产品含量为99.76%.

A new synthesis process in which the Ultraviolet Absorber 327 was synthesized by way of diazotization, coupling, and second reduction of 4-choloro-2-nitro-aniline with glucose and zinc powders as reduction reagents was presented. The effects of sulfuric acid,2,4-di-tert-butyl-phenol and the combinations of different reduction reagents were studied. The results showed that the relative good condition of the process, in which 4-choloro-2-nitro-aniline （a） was diazotized with the help of sulfuric acid （b） and sodium nitrite, and then coupled with 2,4-di-tert-butyl-phenol（c） to form UV-327, was （a） ： （b） ： （c）=1 ： 5.75 ： 1.1（molar ratio）. The combination of glucose and zinc powders proved to be a better reduction reagent than that of sodium sulfide and zinc powders. The objective product was identified with HPLC, 1H-NMR, IR and Ultraviolet spectrum. The total yield was about 83.2% （calculated by using 4-choloro-2-nitroaniline） and its purity was 99.76%.