原位液相催化氮烷基化法反应

以胺和醇为原料，在Ni-Sn/Al2O3催化下液相合成氮烷基胺类化合物。反应工艺为连续式反应，醇既是烷基化试剂，又是供氢体和溶剂。考察了180 ℃下不同的胺与各类醇在Ni-Sn/Al2O3催化作用下的氮烷基化反应。研究表明该烷基化反应具有普遍的适用性，多数胺与甲醇、乙醇、正丁醇反应，具有较高的氮烷基化总产率。一些胺与醇反应产率甚至在99%以上。本文作了催化剂稳定性测试，并通过XRD和TEM对催化剂进行了表征，分析了催化剂失活的原因。研究表明，该催化剂具有很高的稳定性可保持高活性超过480 h，Lewis酸中心是氮烷基化反应的活性中心，随着反应进行，Lewis酸中心转化为Brφnested酸中心，致使催化剂活性降低。

Research on In-Situ Liquid-Phase catalytic hydrogenation for N-alkylation

A clean and efficient method has been developed for N-alkylation of amines catalyzed by Ni-Sn/Al_2O_3 with alcohol as the alkylation agent and solvent as well as hydrogen-donor. For all the reactions, the temperature was 180 ℃, the pressure was 1.5 MPa, and the flow rate was 1.0 mL/min. The structure of the catalyst was confirmed by X-ray diffraction(XRD) and transmission electron microscopy(TEM). The yields of N-alkylation amines were measured by gas chromatography(GC) while their structures were confirmed by gas chromatography-mass spectrometry(GC-MS). The results show that this catalyst has a great conjoint effect for all the reactions in in-situ hydrogenation for N-alkylation, including dehydrogenation of alcohol and hydrogenation of imine intermediates. The total yields of all the N-alkylation products were quite high, and some even greater than 99%. The catalyst had a long life of more than 480 h.