摘要
以邻硝基乙苯为原料、甲醇为亲核试剂对扩展的 Bamberger 反应的条件进行了优化。实验结果表明,采用 Pt 质量分数为3%的 Pt/C 催化剂,在 Pt 与原料邻硝基乙苯的摩尔比为3.06×10^(-4),反应温度为50℃,硫酸浓度[H^+]为4.40 mol/L 时,反应结果最好。在此条件下,以邻硝基乙苯为基准计算,2-乙基-4-甲氧基苯胺的收率可达54.6%。以此条件为基础,对扩展的Bamberger 反应进行了系统性研究。研究结果表明,对于硝基苯及其邻位烷基取代物,邻位空间位阻越大,邻位取代副产物越少,从而对位甲氧基化产物的收率越高。对于不同的亲核试剂,扩展的 Bamberger 反应的收率与亲核试剂的亲核能力有关,亲核能力越强,产物的收率越高。
By using o-nitro ethylbenzene as starting material and methanol as nucleophilic reagents, optimization of extended Bamberger reaction was studied. 3 % Pt/C catalyst is most preferable for this reaction. When mole ratio of platinum to o-nitro ethylbenzene was 3.06 10 ^-4, acid concentration[ H ^＋ ] was 4.40 mol/L and reaction temperature was 50 ℃, the reaction gave the best yield of 54.6% to 2-ethyl-4-methoxy aniline based on o-nitro ethylbenzene. The structure of product was identified by means of IR and NMR. Systematic study on extended Bamberger reaction was carded out under optimal conditions. The extended Bamberger reaction gave moderate yield when using nitrobenzene and its derivatives as starting materials. The more heavy the steric hindrance in ortho position, the less the ortho byproducts, but the higher the para methyloxy product yield. The yield of extended Bamberger reaction was substantially related with nucleophilic ability of nucleophilic reagents, better reaction yield was obtained by using stronger nucleophilic ability of reagents.
出处
《石油化工》
EI
CAS
CSCD
北大核心
2008年第8期827-831,共5页
Petrochemical Technology
作者简介
郭翔海（1977-），男，河北省新河县人，博士，讲师，电话022-27403487，电邮guoxh@tju．edu．cn。
