494871-41-9Relevant academic research and scientific papers
Synthesis and substitution reactions on dicholoro[2-(N-(2-hydroxyphenyl)-carbamoyl)pyridine]bis (dimethylsulphoxide)-ruthenium(II)
Dutta, Sujit,Bhattacharya, Pabitra K.
, p. 262 - 267 (2007/10/03)
The amide ligand 2-(N-(2-hydroxyphenyl)carbamoyl)pyridine (H2L1) has been prepared by condensing pyridine-2-carboxylic acid with 2-aminophenol. This amide ligand has been characterised by elemental analysis, infrared, 1H NMR and mass spectral studies. The complex [Ru(H2L1)(dmso)2Cl2] I, has been synthesised by the reaction of [Ru(dmso)4Cl2] with H2L1. Further reaction of I with π-acidic diimines, 2,2′-bipyridine and 1,10-phenanthroline, lead to the substitution of the coordinated dmso molecules in I forming heteroleptic ruthenium complexes [Ru(bpy)(HL1)Cl2], II and [Ru(phen)(HL1)Cl2], III (bpy = 2,2′-bipyridine and phen = 1,10-phenanthroline), respectively. The complex I is diamagnetic while the complexes II and III are paramagnetic due to one electron and show rhombic EPR spectra at 77K. All the complexes show intense absorptions due to metal to ligand charge transfer (MLCT) transitions in the electronic spectra. The IR and 1H NMR spectral studies indicate that in I, the amide ligands coordinate to the ruthenium (II) ion as a bidentate ligand, coordinating from pyridyl nitrogen and the carbonyl oxygen of the amide linkage, leaving the other potential coordinating phenolic functional group intact. The IR spectral studies indicate that in II and III, the amide ligand coordinates from the pyridyl nitrogen and the amidato nitrogen, leaving the other potential coordinating phenolic functional group intact. The complex I undergoes a reversible ruthenium(II)/ruthenium(III) oxidation at -0.17 V in acetonitrile solution, while the complexes II and III undergo irreversible ruthenium(III)/ruthenium(IV) oxidation at ca. 0.37 V.
