NO_2催化硝化萘制备二硝基萘

Preparation of dinitronaphthalene compounds from the nitration reaction of naphthalene with NO_2 as nitration reagent

提出了一种从"强酸"转移到"非酸",替代传统的"硝酸/硫酸"混酸环境,直接以NO2为硝化剂,在温和条件下催化硝化萘制备二硝基萘的方法,主要考察了催化剂种类、反应物配比、反应温度及反应时间等因素对二氧化氮硝化萘过程的影响。结果表明,Ni(CH3COO)2·4H2O催化剂有较好的催化效果,当萘与二氧化氮的物质的量之比为1∶8,反应温度为100℃,反应时间为3h,萘的转化率可达100%,1,5-二硝基萘的选择性为22.84%,1,3-二硝基萘的选择性为18.59%,1,4-二硝基萘的选择性为11.67%,三种总选择性为53.1%。本文提出了一种环境友好、过程简单且反应条件温和的制备二硝基萘化合物的方法,具有理论和现实指导意义。

A simple method for the preparation of dinitronaphthalene from the nitration reaction of naphthalene with NO2 as nitra-tion reagent instead of nitric-sulfuric mixed acid under the mild conditions has been successfully developed from the＂strong-acid＂to＂non-acid＂method in this work.The effects of different catalysts,the ratio of naphthalene to NO2 ,temperature and reaction time on the nitration were studied.The results indicat that Ni（CH3 COO）2 ·4H2 O catalyst shows better catalytic performances. From the results of single-factor experiment,the optimal reaction conditions are as follows：the reaction temperature is 100 ℃, reaction time is 3 h,and the molar ratio of naphthalene to NO2 is 1：8.The conversion of naphthalene is 100% with 22.84%, 18.59% and 11.67% of the selectivity to 1,5-DNN,1,3-DNN and 1,4-DNN,respectively.The total selectivity of 1,5-DNN,1, 3-DNN and 1,4-DNN is 53.1%.This method has advantages of environmentally benign,simple procedure and mild reaction con-ditions for the preparation of dinitronaphthalene,and it has important theoretical and practical significance.