Synergistic Mechanism of Ru‐NiO _X /C Catalyst for Regioselective Hydrogenation of 2‐Naphthol

Abstract The selective hydrogenation of naphthalene derivatives is a crucial transformation for synthesizing valuable intermediates in pharmaceuticals and functional materials. This work presents a highly efficient Ru‐NiO X /C catalyst, fabricated through a facile deposition method, for the regioselective hydrogenation of 2‐naphthol to 5,6,7,8‐tetrahydro‐2‐naphthol (5,6,7,8‐THN‐2‐ol)—a key synthon for antifungal and antimalarial agents. The reaction parameters, including temperature, H 2 pressure, time, and solvent, were systematically regulated. Under optimized conditions (70 °C, 4 MPa H 2 , isopropanol), the catalyst achieved complete conversion of 2‐naphthol with 72.9% selectivity to 5,6,7,8‐THN‐2‐ol. An exceptional production rate of 170.1 mmol/g metal ·h was attained, surpassing most reported heterogeneous catalysts, alongside excellent recyclability over three cycles (full conversion, yield rate > 163.2 mmol/g metal ·h). Combined characterization (HAADF#x02010;STEM、XPS, H 2 ‐TPR, color change of WO 3 ) revealed that the superior performance of the Ru‐NiO X /C catalyst arose from the synergistic effect of the Ru‐NiO X system, the high dispersion of active metals and hydrogen spillover. Density functional theory (DFT) calculations revealed that the Ru‐NiO X system strengthens the adsorption of reactant molecules. Additionally, the over‐hydrogenated byproduct decahydro‐2‐naphthol was shown to form preferentially through further hydrogenation of the intermediate 1,2,3,4‐tetrahydro‐2‐naphthol (1,2,3,4‐THN‐2‐ol). This study offers a general strategy for designing highly active and selective catalysts for the hydrogenation of naphthalene derivatives.