Synthesis and characterization of mixed ligand complexes of cobalt(II) with some nitrogen and sulfur donors

Abstract

Mixed ligand complexes of Co(II) with nitrogen and sulfur donors, Co(OPD)(S–S) · 2H₂O and Co(OPD)(S–S)L₂ [OPD = o-phenylenediamine; S–S = 1,1-dicyanoethylene-2,2-dithiolate (i-MNT²⁻) or 1-cyano-1-carboethoxyethylene-2,2-dithiolate (CED²⁻); L = pyridine (py), α-picoline (α-pic), β-picoline (β-pic), or γ-picoline (γ-pic)], have been isolated and characterized by analytical data, molar conductance, magnetic susceptibility, electronic, and infrared spectral studies. The molar conductance data reveal non-electrolytes in DMF. Magnetic moment values suggest low-spin and high-spin complexes. The electronic spectral studies suggest distorted octahedral stereochemistry around Co(II) in these complexes. Infrared spectral studies suggest bidentate chelating behavior of i-MNT²⁻, CED²⁻, or OPD while other ligands are unidentate in their complexes.

Keywords:

• Cobalt(II)
• 1,1-Dithiolates
• Nitrogen donors
• Mixed ligand complexes

Acknowledgements

The authors are grateful to the Head, RSIC, NEHU, Shillong for microanalysis and recording of IR spectra. Help received from the Head of the Department of Chemistry, B.H.U., Varanasi, and Head of the Department of Inorganic Chemistry, Indian Association for Cultivation of Science, Kolkata, for measuring magnetic susceptibility is also acknowledged. One of the authors (Mrs. Bijaya Paul) is grateful to Mr. P.K. Das, donor of Pyari Mohan LabanyaPrabha Memorial (PMLPM) Research Fellowship, for financial assistance.