活性炭负载纳米镍催化葡萄糖还原胺化反应

在活性炭存在下硼氢化钠还原氯化镍制备了炭负载纳米镍（Ni/AC），用扫描电镜、透射电镜、X射线衍射分析表征了催化剂的结构，以一步法葡萄糖的还原胺化合成葡甲胺的反应为模型，考察了催化剂的制备、催化反应条件等因素对葡甲胺产率的影响。产物结构经核磁共振波谱表征。葡萄糖与甲胺先形成环状甲胺基葡萄糖，进而在催化剂作用下被还原成葡甲胺。研究发现，催化剂制备过程中的NaCl对催化反应具有抑制作用。三乙胺的加入能够提高催化剂的催化性能。在n_葡萄糖∶n_Ni=9∶1，n_葡萄糖∶n_甲胺=1∶1.8，n_Ni∶n_三乙胺=1∶2.5，80 ℃及氢气5.0 MPa下反应1 h，葡甲胺的产率达到了98%。

Catalytic reductive amination of glucose promoted by nano Ni supported on active carbon

Supported nickel（Ni/AC）was prepared by reduction of NiCl₂ with NaBH₄ in the presence of activated carbon. The catalyst（Ni/C）was characterized by SEM，TEM，and XRD. The effects of preparation and catalytic reaction conditions on catalytic activity were evaluated by using reductive amination of glucose with methylamine as a model reaction. The reaction product was analyzed by NMR. The glucose reacted with methylamine to form cyclo-methylamino-glucose，then was reduced under the action of the catalyst to form N-methyl-D-glucamine. The NaCl formed in the reduction preparation of the catalyst inhibited the catalytic reductive amination. The catalyst performance could be improved by adding triethylamine. The yield of N-methyl-D-glucamine was up to 98% at reaction temperature of 80 ℃，H₂ pressure of 5.0 MPa，molar ratio of glucose to Ni，glucose to MeNH₂ and glucose to Et₃N 9∶1；1∶1.8 and 1∶2.5，respectively.