Syntheses, spectral and structural studies of Schiff base complexes of η5-pentamethylcyclopentadienyl rhodium and iridium

The compounds [(η5-C5Me5)M(μ-Cl)Cl}2] where M=Rh (1) and Ir (2) react with N,N′-donor chelating ligands, viz., para-substituted N-(pyrid-2-ylmethylene)phenylamines (2-PP) in methanol–acetone to afford the pentamethylcyclopentadienyl rhodium (III) and iridium (III) derivatives of the type [(η5-C5Me5)MCl(C5H4N-2-CHN–C6H4-p-X]+ (M=Rh, 3; M=Ir, 4), where C5Me5 =pentamethylcyclopentadienyl; X=H (3a, 4a), CH3 (3b, 4b), OCH3 (3c, 4c), Cl (3d, 4d), NO2 (3e, 4e), respectively. These compounds were characterized by FT-IR and FT-NMR spectroscopy as well as analytical data. The molecular structures of the tetrafluoroborate salt of [(η5-C5Me5)RhCl(C5H4N-2-CHN–C6H4-p-Cl)]+ (3d) and hexafluorophosphate salt of [(η5-C5Me5)IrCl(C5H4N-2-CHN–C6H4-p-NO2)]+ (4e) were established by single crystal X-ray diffraction studies.