中试规模合成邻硝基苯乙醇

该文研究了重要中间体邻硝基苯乙醇的合成工艺。结果表明,对于邻硝基甲苯的羟甲基化反应,效果最好的催化剂为氢氧化钠水溶液,且质量分数为20%的氢氧化钠水溶液的催化效果最佳,强碱型阴离子交换树脂因溶于二甲亚砜不适用于该反应。在质量分数20%的氢氧化钠水溶液催化下,羟甲基化反应最佳反应温度为50℃,甲醛与邻硝基甲苯的最佳摩尔比为0.4~0.5。在该条件下,按已转化的邻硝基甲苯计,邻硝基苯乙醇质量收率为110%,摩尔收率为90.7%。产品邻硝基苯乙醇的结构经红外、核磁等表征确证。该实验结果已经经过一次性投邻硝基甲苯120 kg的生产型中试验证,邻硝基苯乙醇质量收率为105.2%,摩尔收率为86.7%。

Scale-up Synthesis of o-Nitrophenylethanol

The synthetic process of important intermediate o-nitrophenylethanol was studied.Results showed that,with w(NaOH)=20% aqueous solution as alkaline catalyst,at a temperature of 50 ℃ and formaldehyde to o-nitrotoluene molar ratio of 0.4～0.5,best result was obtained.Under these optimized conditions,taking account of recovered o-nitrotoluene,o-nitrophenylethanol was afforded in mass yield of 110% and molar yield of 90.7%.The product was confirmed by IR and 1H,13CNMR.The result of our experiments was proved by productive scale-up test,in which 120 kg o-nitrotoluene was used as raw material to afford o-nitrophenylethanol in a mass yield of 105.2% and a molar yield of 86.7%.