[Bmim]OAc-0.5Zn(OAc)_(2)催化合成甲苯二氨基甲酸甲酯反应性能及机理  

Reaction performance and mechanism for synthesis of toluene dicarbamate catalyzed by [Bmim]OAc-0.5Zn(OAc)2

作　　者：王桂荣[1] 闫云 仝甜 赵新强[1] 王延吉[1] WANG Gui-rong;YAN Yun;TONG Tian;ZHAO Xin-qiang;WANG Yan-ji(School of Chemical Engineering,Hebei University of Technology,Tianjin 300130,China)

机构地区：[1]河北工业大学化工学院,天津300130

出　　处：《高校化学工程学报》2023年第1期68-79,共12页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金(U21A20306,21236001)。

摘　　要：采用红外光谱、核磁共振氢谱等实验手段,通过催化剂筛选和单因素实验对[Bmim]OAc-0.5Zn(OAc)_(2)催化甲苯二胺(TDA)与碳酸二甲酯(DMC)合成甲苯二氨基甲酸甲酯(TDC)反应进行研究。结果表明,[Bmim]OAc-0.5Zn(OAc)_(2)为该反应的较优催化剂,[Bmim]OAc-0.5Zn(OAc)_(2)中乙酸锌为单齿配位结构;在80℃下反应3 h,制得的[Bmim]OAc-0.5Zn(OAc)_(2)催化性能较好。在物质的量比n(TDA):n(DMC)=1:30,质量比m(TDA):m([Bmim]OAc-0.5Zn(OAc)_(2))=1:0.95,160℃,反应6 h的条件下,TDC收率达94.50%。[Bmim]OAc-0.5Zn(OAc)_(2)催化合成TDC的反应机理为:[Bmim]OAc-0.5Zn(OAc)_(2)中的Zn^(2+)与DMC中的羰基氧作用形成新配合物,同时活化了羰基碳;乙酸根与TDA中的氨基作用形成氢键,并活化TDA;被活化的TDA进攻新配合物中被活化的羰基碳,促进了甲氧羰基化反应的进行,生成产物TDC。The synthesis of toluene dicarbamate (TDC) from toluene diamine(TDA) and dimethyl carbonate(DMC) catalyzed by[Bmim]OAc-0.5Zn(OAc)2was investigated by means of Fourier transform infrared spectrometry and H nuclear magnetic resonance through catalyst screening and single factor experiment.The results showed that[Bmim]OAc-0.5Zn(OAc)2was better catalyst for TDC synthesis,and the zinc acetate in[Bmim]OAc-0.5Zn(OAc)2was a monodentate coordination structure.The prepared[Bmim]OAc-0.5Zn(OAc)2had good catalytic performance after for 3 h at 80℃.TDC yield of 94.5%could be obtained under the condition of molar ratio of TDA/DMC=1/30,mass ratio of TDA/[Bmim]OAc-0.5Zn(OAc)2=1/0.95,reaction temperature of160℃,and reaction time of 6 h.The reaction mechanism of TDC synthesis could be speculated as follows:Zn^(2+)in[Bmim]OAc-0.5Zn(OAc)2reacts with carbonyl oxygen in DMC to form a new coordination complex,which activates carbonyl carbon;acetate reacts with amino group in TDA to activate TDA;the activated TDA attacks the activated carbonyl carbon in the new complex to proceed methoxycarbonylation reaction and generate product TDC.

关 键 词：[Bmim]OAc-0.5Zn(OAc)_(2) 碳酸二甲酯(DMC) 甲苯二氨基甲酸甲酯(TDC) 反应机理 

分 类 号：TQ323.8[化学工程—合成树脂塑料工业]