Ru/Zr(OH)4 as a Transfer Hydrogenation Catalyst under Additives‐Free Condition

Abstract Ru/Zr(OH) 4 was developed as an effective transfer hydrogenation catalyst for a broad substrate scope, including nitro, alkene, and aldehyde/ketones groups without additives. XPS study and catalyst evaluation indicated that Ru 0 was the main active catalytic species during the reaction. FT‐IR and CO 2 ‐TPD analysis showed that Zr(OH) 4 has abundant basic sites. The synergistic effect of Ru metal and basic sites of Zr(OH) 4 support provides Ru/Zr(OH) 4 with good catalytic activity without additional base addition. Ru−H− active species was detected by 1 H solid‐state NMR, and the mechanism of nitrobenzene transfer hydrogenation was proposed. Ru/Zr(OH) 4 catalyst was stable and can be reused for at least 5 cycles with only slight loss of activity and selectivity. This methodology provides an environmentally benign process for transfer hydrogenation under additives‐free conditions with the advantages of high activity, stability, and broad substrate scope.