三光气合成碳酸二(4-硝基苯基)酯工艺研究

文章对三光气(BTC)与对硝基苯酚(PNP)反应合成碳酸二(4-硝基苯基)酯(BPNPC)的方法进行了改进.考察了催化剂、投料比、温度等因素对产率的影响,并借助熔点、FT-IR对产物的结构进行了表征.结果表明,在碳酸二(4-硝基苯基)酯合成中使用的相转移催化剂四乙基溴化铵对受界面扩散控制的BTC气与对硝基酚钠反应有良好的相转移催化效果;氢氧化钠质量分数较低时,酚钠盐向溶有BTC的油相扩散速度较小,较高时会产生氯甲酸对硝基苯酯;温度较低、BTC量较高时,会产生少量氯甲酸对硝基苯酯,BTC用量较低会使反应不完全,这些都影响着收率.优化后的合成工艺条件为:低毒、可回收的二氯甲烷为溶剂,反应摩尔比n(BTC):n(NaOH):n(PNP)=1.0:1.05:6.4,反应温度25℃,氢氧化钠质量分数17%;在此优化工艺条件的产率为95.2%.

Study on synthesis technology of bis(4-Nitrophenyl)carbonate by the triphosgene method

In this paper,synthesis technology of bis(4-nitrophenyl)carbonate(BPNPC)using bis(trichloromethyl)carbonate(BTC)with 4-Nitrophenol(PNP)was optimized.Effects of reaction temperature,catalyzator and feed ratio on synthesis of the product were investigated.The chemical structure of the product was characterized by means of the melting point and IR.The results show that tetraethylammonium bromide which was used as a phase transfer catalyst in this reaction had optimization effect on the interfacial diffusive reaction of BTC and PNP.Higher concentration of sodium hydroxide,lower temperature and a higher dosage of BTC produced a small amount of 4-nitrophenyl chloroformate,while lower concentration of sodium hydroxide and a lower dosage of BTC made reaction incomplete,which affected the yield.Optimal conditions for preparation of BPNPC were as follows:reeoverable dichloromethane with low toxicity was used as the solvent,tetraethylammonium bromide was added at 25℃,n(BTC):n(NaOH):n(PNP)=1.0:1.05:6.4,and the sodium hydroxide concentration was 17%,and thus the highest yield could reach 95.2%.