Reversal Effect of Phosphorus on Catalytic Performances of Supported Nickel Catalysts in Reductive Amination of 1,6‐Hexanediol.

The reductive amination of 1,6‐hexanediol with ammonia is one of the most promising green routes for synthesis of 1,6‐hexanediamine. Herein, we developed a phosphorous modified Ni catalyst of Ni−P/Al2O3. It presented satisfactory improved selectivity to 1,6‐hexanediamine in the reductive amination of 1,6‐hexanediol compared to the Ni/Al2O3 catalyst. The phosphorous tended to interact with Al2O3 to form AlPOx species, induced Ni nanoparticle to be flatter, and the decrease of strong acid sites, the new‐formed Ni−AlPOx−Al2O3 interface and the flatter Ni nanoparticle were the key to switch the dominating product from hexamethyleneimine to 1,6‐hexanediamine. This work develops an efficient catalyst for production of 1,6‐hexanediamine from the reductive amination of 1,6‐hexanediol, and provides a point of view about designing selective non‐noble metal catalysts for producing primary diamines via reductive amination of diols. [ABSTRACT FROM AUTHOR]