Highly Dispersed Ru Nanoclusters Anchored on Hexagonal Boron Nitride for Efficient and Stable Hydrogenation of Aromatic Amines to Alicyclic Amines

Saturated hydrogenation of aromatic amines is a crucial methodology for synthesizing alicyclic amines. The dispersion of Ru atoms occurred after chemical reduction treatment, which was constrained to B and N coordination, further promoting the Ru species' uniform distribution through interaction with the B–N bond of boron nitride. Moreover, the Ru coordinated with h-BN and further formed the stable catalytic active center. By virtue of its excellent stability, the hydrogenation of MDA executed in the fixed-bed reactor could run for more than 200 h. However, the density functional theory showed that the hydrogenation rate of the second benzene ring was comparatively slower because of the strong intermediate adsorption during the conversion from 4,4′-diaminodiphenylmethane to 4,4′-diaminodicyclohexylmethane. Furthermore, Ru/h-BN exhibited excellent performance in the hydrogenation of other aromatic amines, resulting in corresponding alicyclic amines. Therefore, this research offers a stable and effective catalyst for the green hydrogenation of aromatic amines leading to the production of alicyclic amines.