| Abstract: | Neutral half‐sandwich η6‐p ‐cymene ruthenium(II) complexes of general formula Ru(η6‐p ‐cymene)Cl(L)] (HL = monobasic O, N bidendate benzoylhydrazone ligand) have been synthesized from the reaction of Ru(η6‐p ‐cymene)(μ‐Cl)Cl]2 with acetophenone benzoylhydrazone ligands. All the complexes have been characterized using analytical and spectroscopic (Fourier transform infrared, UV–visible, 1H NMR, 13C NMR) techniques. The molecular structures of three of the complexes have been determined using single‐crystal X‐ray diffraction, indicating a pseudo‐octahedral geometry around the ruthenium(II) ion. All the ruthenium(II) arene complexes were explored as catalysts for transfer hydrogenation of a wide range of aromatic, cyclic and aliphatic ketones with 2‐propanol using 0.1 mol% catalyst loading, and conversions of up to 100% were obtained. Further, the influence of other variables on the transfer hydrogenation reaction, such as base, temperature, catalyst loading and substrate scope, was also investigated. |
