对硝基甲苯合成对硝基苯乙醛新工艺考察  

Investigation on New Synthetic Process of p-Nitrophenylacetaldehyde from p-Nitrobenzene

作　　者：俞杰 ZHYLKO Viachaslau YU Jie;ZHYLKO Viachaslau(College of Biology and Environmental Engineering,Zhejiang Shuren University,Hangzhou 310015,China;International Sakharov Environmental Institute,Belarusian State University,Minsk 220070,Republic of Belarus)

机构地区：[1]浙江树人大学生物与环境工程学院,浙江杭州310015 [2]白俄罗斯国立大学国际萨哈罗夫环境研究所,白俄罗斯明斯克220070

出　　处：《化学反应工程与工艺》2019年第6期564-569,共6页Chemical Reaction Engineering and Technology

基　　金：2019浙江省科技厅省级引智项目;浙江树人大学人才引进项目(2017R001)。

摘　　要：研究了一种以对硝基甲苯为原料,通过缩合及水解两步法合成对硝基苯乙醛的新工艺。考察了N,N-二甲基二甲缩醛(DMFDMA)用量、N,N-二甲基甲酰胺(DMF)用量对中间体N,N-二甲基-2-(4-硝基苯基)-乙烯胺合成的影响,以及酸种类、酸浓度和反应温度对烯胺水解合成对硝基苯乙醛的影响。目标产品经1H-核磁(1H-NMR)鉴定。结果表明,增加缩醛DMFDMA用量可提高N,N-二甲基-2-(4-硝基苯基)-乙烯胺的收率,DMFDMA与对硝基甲苯的较佳物质的量比为2:1;溶剂DMF有利于缩醛DMFDMA分解,从而提高N,N-二甲基-2-(4-硝基苯基)-乙烯胺的收率,较优的DMF用量为20 mL;盐酸为优选的烯胺水解试剂,适宜的盐酸浓度为1 mol/L;较低和较高的烯胺水解温度均会使得对硝基苯乙醛的收率降低,较佳水解温度为30℃。优化的反应条件下,缩合制备N,N-二甲基-2-(4-硝基苯基)-乙烯胺的收率为90.0%,水解制备对硝基苯乙醛的收率为90.8%,两步反应总收率为81.7%,具有良好的工业应用前景。A new process for the synthesis of p-nitrophenylacetaldehyde by a two-step method of condensation and hydrolysis using p-nitrotoluene as starting material was developed.The effects of dosage of N,N-dimethylformamide dimethyl acetal(DMFDMA)and N,N-dimethylformamide(DMF)on the preparation of N,N-dimethyl-2-(4-nitrophenyl)-ethenamine,and the effects of acid type,acid concentration and reaction temperature on the preparation of p-nitrophenylacetaldehyde by hydrolysis of enamine were investigated.The target product was identified by 1H-NMR.The results showed that the yield of N,N-dimethyl-2-(4-nitrophenyl)-ethenamine increased by increasing the dosage of DMFDMA,and the optimal molar ratio of DMFDMA to p-nitrotoluene was 2:1.The solvent DMF was favorable for the decomposition of DMFDMA so that the yield of N,N-dimethyl-2-(4-nitrophenyl)-ethenamine increased,and the optimal amount of DMF was 20 mL.Hydrochloric acid was the optimal reagent for the hydrolysis of enamine,and the appropriate concentration of hydrochloric acid was 1.0 mol/L.And the optimal hydrolysis temperature was 30℃.Under the optimized reaction conditions,the yield of N,N-dimethyl-2-(4-nitrophenyl)-ethenamine prepared by condensation was 90.0%,the yield of p-nitrophenylacetaldehyde prepared by hydrolysis was 90.8%,and the total yield of the two-step reaction was 81.7%,which is promising for industrial application.

关 键 词：对硝基甲苯 对硝基苯乙醛 烯胺 N N-二甲基二甲缩醛 

分 类 号：O624.41[理学—有机化学]