【摘要】 在碱性介质中,以Pd/C为催化剂,对邻硝基氟苯催化加氢制备2,2’-二氯氢化偶氮苯(DHB)进行研究,采用正交法对加氢还原进行了条件优化,优化条件为:反应温度65℃氢氧化钠质量浓度为:538g/l;Pd/C用量为4.0%;助催化剂NQON用量为2.67%。在该条件下催化剂可重复使用6次,所得产物DHB质量分数大于94.5%。在强酸性条件下,将DHB重排得5,3’二氯联苯胺盐酸盐,重排反应收率为90.0%,总收率85.0%。更多还原

【Abstract】 2,2’-Dichlorohydrobenzene(DHB)was prepared by catalytic hydrogenation of 2-nitrochlorobenzene using Pd/C as a catalyst in alkaline medium. The optimum reaction conditions were determined by orthogonal experiments as follows: reaction temperature was 65 ℃; concentration of NaOH was 538gL-1; the ratio of Pd/C catalyst to 2-nitrochlorobenzene was 4.0%; the amount of NQON was 2.67%; Pd/ C catalyst could be recycled at least six times under the optimum conditions, and the yield of DHB was > 94.5%.DHB was rearranged in strong acid medium to give 3,3’-dichlorobenzidine (DCB) with a yield of 90.0%, the overall yield was 85.0%.更多还原