Synthesis, thermal, electrochemical and catalytic behavior toward transfer hydrogenation investigations of the half-sandwich RuII complexes with 2-(2′-quinolyl)benzimidazoles

Abstract

A series ligands (L3-14) of derived from 2-(2′-quinolyl)benzimidazole (QuBim, L1) and 2-(2′-quinolyl)-5,6-dimethylbenzimidazole (QuDmBim, L2) which are an NN-type ligands have been synthesized and characterized with various techniques such as NMR, UV–vis, FT-IR spectroscopy, elemental analysis and X-ray diffraction. The substituted ligands derived from QuBim and QuDmBim have been used as sustaining ligands in the RuII-catalyzed transfer hydrogenation (TH) of acetophenone to secondary alcohols in the presence i-PrOH/KOH. The half-sandwich complexes (C1-14) of RuII with NN-type ligands have been synthesized by cleavage of [(η6-p-cymene)Ru(μ-Cl)]2 dimer. The resulting complexes have been characterized by NMR, UV–vis, FT-IR spectroscopy and elemental analysis. The thermal and electrochemical properties of selected complexes and ligands were investigated.