Investigation on New Synthetic Process of p-Nitrophenylacetaldehyde from p-Nitrobenzene
1. College of Biology and Environmental Engineering, Zhejiang Shuren University, Hangzhou 310015, China;
2. International Sakharov Environmental Institute, Belarusian State University, Minsk 220070, Republic of Belarus
Abstract：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.
YU Jie1,ZHYLKO Viachaslau2. Investigation on New Synthetic Process of p-Nitrophenylacetaldehyde from p-Nitrobenzene[J]. 化学反应工程与工艺, 2019, 35(6): 564-569.
