HYDROGENATION OF α,β-UNSATURATED CARBONYL COMPOUNDS CATALYZED BY RUTHENIUM(II) COMPLEXES

Abstract

Four new ruthenium(II) complexes containing 8-methyl-2-oxo-1,2-dihydroquinoline-3-carbaldehyde-4(N)-substituted thiosemicarbazones (HL1-4) were synthesized. Characterization of the compounds was done by using spectral techniques such as IR, UV–Vis, NMR and Mass spectrometry, which confirmed their stoichiometric formation. The structure of the complexes was confirmed by X-ray crystallography where the ligands coordinated as N,S bidentate monoanionic donor. Based on the above data, an octahedral structure has been confirmed for the complexes. Ruthenium complexes were tested for their catalytic efficiency in hydrogenation of rigid alkenes where by the C=O and C=C groups of alkenes were reduced in the presence of NaBH4 as a hydrogen source and these hydrogenated products were conformed by 1H, 13C, GC-MS and CD spectral analysis. The reusability and morphological change of the catalyst was analysed by powder XRD and SEM images.