Ruthenium(II) half-sandwich complexes containing N-substituted 5-nitrobenzimidazole: Synthesis, structures and catalytic transfer hydrogenation of ketones

In this study,N-substituted 5-nitrobenzimidazole ligands were reacted with [RuCl2(p-cymene)]2  and the corresponding complexes  were prepared and their structure were elucidated by elemental analysis, IR and NMR spectroscopic techniques. The synthesized Ru(II) complexes  were tested as catalysts for the transfer hydrogenation (TH) of acetophenone to secondary alcohols in the presence of KOH using 2–propanol as a hydrogen source at 82 ºC. This complexes was found to be an active catalyst in the catalytic transfer hydrogenation of ketones.

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