New Ruthenium-p-Cymene Complexes Containing o-Vanillin and 4-Benzoxybenzaldehyde Schiff Base Ligands; Synthesis, Characterization and Catalytic Activity in the Transfer Hydrogenation of Ketones

Abstract

In this work, we reported the synthesis of ruthenium-p-cymene-Schiff base complexes (KB-1, KB-2) containing Schiff base ligands with the transfer hydrogenation (TH) of a series of ketones. The KB-1 and KB-2 complexes were characterized and used by different spectroscopic techniques, including H-1 and C-13-NMR, FT-IR, mass, TGA, microanalysis and UV-Vis spectroscopy. The various characterization data suggested that Schiff base ligands coordinated through O atom of carbonyl group, N atom of azomethine and deprotonated phenolic O atoms with Ru metal ion in (2:1) molar ratio having the general formulas [Ru(p-cymene)L1]center dot Cl center dot 0.5H(2)O and [RuCl(p-cymene)L2]center dot Cl. Molecular structures of KB-1 and KB-2 complexes were found as pseudo-octahedral geometry. The complexes were screened as catalysts in the TH reactions. The results have revealed that KB-1 and KB-2 complexes showed efficient catalytic activity for the TH of ketones. [GRAPHICS]