Insight into the mechanism of 3,3′-dimethyl-4,4′-diaminodiphenylmethane synthesis over Hβ zeolite
作者:Yingkuo Yang、Yingxian Zhao、Jianhua Shao、Shengjian Zhang、Rongqiang Yang
DOI:10.1016/j.molcata.2014.10.028
日期:2015.3
Heterogeneous synthesis of 3,3′-dimethyl-4,4′-diaminodiphenylmethane (MDT) from o-tolylamine and formaldehyde on acidic zeolites HY, HZSM-5, Hβ and TS-1 was investigated. Hβ zeolite with strong Bronsted acidity and proper textural property demonstrated better catalytic performance than other three zeolites for this synthetic reaction. Yield and selectivity of product MDT from the catalytic reaction
研究了在酸性沸石HY,HZSM-5,Hβ和TS-1上由邻甲苯胺和甲醛异构合成3,3'-二甲基-4,4'-二氨基二苯甲烷(MDT)。具有强布朗斯台德酸度和适当质构性质的Hβ沸石在该合成反应中显示出比其他三种沸石更好的催化性能。Hβ催化反应产物MDT的收率和选择性强烈依赖于温度,最佳反应温度约为433K。根据LC / MS和1 H NMR分析反应中间体,表明合成方法经历了涉及中间体邻甲苯基氨基甲醇,亚甲基邻甲苯基胺,N,N的多个步骤′-二-邻甲苯基-甲二胺和2-甲基-4-(邻甲苯基氨基-甲基)-苯胺。解释了各种中间体的形成和转化机理。