Reductive amination of 1,6-hexanediol with a modified Ru/Al2O3 catalyst

The synthesis of 1,6–hexamethylenediamine via the reductive amination of 1,6–hexanediol is a fascinating green process and a challenging topic. We developed a kind of Ru/PRL(x)–Al2O3 catalyst for the reductive amination of 1,6–hexanediol, the active Ru species was highly dispersed and anchored by the CNx species formed from 1,10-phenanthroline (PRL). The Ru particle dispersion, electronic interaction, and acid–basic property as well as the catalytic mechanism and the rate determining step were discussed in detail. The new and more acid–base pairs formed, and the electron deficient Ru species and smaller nanoparticles are responsible for the improved catalytic performances of Ru/PRL–Al2O3 catalyst. The yield of 1,6–hexamethylenediamine could reach to 54%, which is the best results reported up to now. The present catalytic process is of great potential for industrial application as it is a green process compared to the traditional method for 1,6–hexamethylenediamine production.