Half-sandwich η6-arene ruthenium and Cp∗ rhodium/iridium compounds comprising with thioether ligands: Synthesis, spectral and molecular studies

• Half sandwich platinum group metal complexes with thioether ligands were isolated.
• Variation of thioether moiety is shown that formation of mono/dinuclear complexes.
• Only few compounds reported among the flexible thioethers with platinum group metals.

The reaction of [(η6-arene)Ru(μ-Cl)Cl]2 and [Cp∗M(μ-Cl)Cl]2 (M = Rh, Ir) with tetradentate N,N′-donor chelating ligand viz 3,6-bis(2-thiopyridyl)pyridazine(L1) leads to the formation of mononuclear compounds as general formula [(arene)MCl(L1)]+ {M = Ru, arene = C6H6 (1); p-iPrC6H4Me (2); C6Me6 (3); Cp∗, M = Rh (4); Cp∗, M = Ir (5)} where as 4,6-bis(2′-thiopyridyl)pyrimidine(L2) and 2,3-bis(2-thiopyridyl)pyrazine(L3) leads to the formation of dinuclear compounds as general formula [{(arene)MCl}2(L)]2+ {M = Ru, L = L2, arene = C6H6 (6); p-iPrC6H4Me (7); C6Me6 (8); Cp∗, M = Rh, (9); Cp∗, M = Ir, (10) and L = L3 C6H6 (11); p-iPrC6H4Me (12); C6Me6 (13), Cp∗, M = Rh, (14) Cp∗, M = Ir (15)}, respectively. The cationic complexes have been isolated as their PF6/SbF6 salts and characterized by FT-IR, UV–Vis, 1H NMR, Mass spectroscopic methods. X-ray crystallographic studies of some representative compounds revealed that typical piano-stool geometry around the metal center with a six-membered metallocycles in which thioether ligand acts as a N,N′-chelating ligand. Variation of bridging motifs of thioether ligands is revealed that formation of mono/dinuclear complexes. The L1 ligand yielded predominantly mononuclear compounds where as L2 and L3 yielded dinuclear compounds with trans and cis isomers, respectively.

A series of arene ruthenium and Cp∗ rhodium/iridium compounds comprising with 3,6-bis(2-pyridylthio)pyridazine(L1)/4,6-bis(2-pyridylthio)pyrimidine(L2)/2,3-bis(2-pyridylthio)pyrazine(L3) as a thioether ligand have been synthesized and representative compounds have been determined by single crystal X-ray diffraction studies.Figure optionsDownload as PowerPoint slide