Isothiocyanate and selenocyanate complexes of Cu(II), Ni(II), and Co(II) with a pyridylpyrazole-based ligand: synthesis, characterization, and structure

Abstract

Mononuclear NCS⁻ containing complexes, [M(NCS)₂L] (L = N,N-bis(3,5-dimethylpyrazol-1-ylmethyl)aminomethylpyridine), [Cu(NCS)₂L′] (L′ = N-(3,5-dimethylpyrazol-1-ylmethyl)aminomethylpyridine), and NCSe⁻ containing complexes [ML(NCSe)(H₂O)]ClO₄ (M = Ni⁺², Co⁺²) have been synthesized and characterized by elemental analysis, spectroscopic, and physico-chemical methods. Structural studies of [Cu(NCS)₂L′] show copper is five coordinate with distorted trigonal bipyramidal geometry with two cis NCS⁻. [M(NCS)₂L] and [ML(NCSe)(H₂O)]ClO₄ (M = Ni⁺² and Co⁺²) are expected to be octahedral.

Keywords:

• Cu(II), Ni(II), and Co(II) complexes
• Tetradentate ligand
• Tridentate ligand
• NCS⁻ and NCSe⁻ ions
• Mononuclear complex
• Crystal structure

Acknowledgments

ZM is thankful to UGC for providing a fellowship (RFSMS). The authors are thankful to Prof. N.D. Kulkarni and Dr R.B. Yadav for magnetic measurements and SAIF, Punjab University, Chandigarh, for providing mass spectral data.