A selective reductive amination of aliphatic aldehydes and cycloaliphatic ketones is achieved with tetragonal zirconium dioxide (t-ZrO₂) as the catalyst. With N, N-dimethyl formamide (DMF) as the solvent, low-molecular-weight amine source and reductant, a more than 99 % yield of N, N-dimethylpentan-1-amine or N, N-dimethyl cyclohexanamine was obtained when n-pentanal or cyclohexanone was used as the substrate. Particularly, the crystallographic structures exhibit a significant effect on catalytic performance where the tetragonal crystalline was preferable to monoclinic one during the reductive amination reaction. In addition, the recycling experiments of catalysts indicate that t-ZrO₂ still kept a high catalytic activity even after being reused five times. From the result of DFT calculations, it is concluded that the crystalline of zirconium dioxide is closely related to the charge transferring rate between the catalyst and the adsorbed reactant. Finally, based on the experiment phenomena and simulation result, a possible reaction mechanism is proposed for the reductive amination of cyclohexanone.

以四方二氧化锆（t -ZrO ₂）为催化剂，可实现脂肪族醛和脂环族酮的选择性还原胺化。当使用N，N-二甲基甲酰胺（DMF）作为溶剂，低分子量胺源和还原剂时，N，N-二甲基戊-1-胺或N，N-二甲基环己胺的收率超过99％。正戊醛或环己酮用作底物。特别地，晶体结构对催化性能表现出显着影响，其中四方晶体优选于在还原胺化反应过程中是单斜的。另外，催化剂的再循环实验表明，即使被重复使用五次，t -ZrO ₂仍保持高催化活性。从DFT计算的结果可以得出结论，二氧化锆的晶体与催化剂和吸附的反应物之间的电荷转移速率密切相关。最后，根据实验现象和模拟结果，提出了可能的环己酮还原胺化反应机理。