Synthesis and Characterization of Half‐Sandwich Ruthenium Complexes Containing Aromatic Sulfonamides Bearing Pyr­id­inyl Rings: Catalysts for Transfer Hydrogenation of Acetophenone Derivatives

Abstract

AbstractN‐(Quinoline‐8‐yl‐aryl)benzenesulfonamides 1–6 were successfully synthesized by the reaction of 8‐aminoquinoline and various benzenesulfonyl chlorides. Then, half‐sandwich ruthenium complexes 7–12 were prepared from the reactions of 1–6 with [RuCl2(p‐cymene)]2. The synthesized compounds were characterized by NMR and FTIR spectroscopy and elemental analysis, and compounds 8 and 9 were further analyzed by X‐ray diffraction. The complexes were screened for their efficiency as catalysts in the transfer hydrogenation of acetophenone derivatives to phenylethanols in the presence of KOH with 2‐propanol (as hydrogen source) at 82 °C, and they all showed good activity. Complexes 10 and 12 were the most active (turnover frequency values: 703 and 734 h–1, respectively).