Synthesis, Physico‐Chemical Characterization and Bio‐Activity of Cobalt(II) Tetrathiocyanato Diargentate(I) Complexes with Some Acylhydrazones

Abstract

Heterobimetallic complexes of the type Co[Ag(SCN)₂]₂ · L(where L=acetophenone benzoylhydrazone (abh), acetophenone isonicotinoyl hydrazone (ainh), acetophenone salicyloyl hydrazone (ash), acetophenone anthraniloyl hydrazone (aah), p‐hydroxy acetophenone benzoylhydrazone (phabh), p‐hydroxy acetophenone isonicotinoyl hydrazone (phainh), p‐hydroxy acetophenone salicyloyl hydrazone (phash), p‐hydroxy acetophenone anthraniloyl hydrazone (phaah) were synthesized and characterized by various physico‐chemical techniques. The complexes are non‐electrolytes and form a polymeric structure by bridging SCN groups between two metal centers. The ligands are coordinated through >C˭O and >C˭N‐groups. Magnetic susceptibility measurements and electronic spectra suggest a tetrahedral geometry for Co[Ag(SCN)₂]₂ and spin free octahedral geometry for all the complexes. Thermal analysis (TGA and DTA) of Co[Ag(SCN)₂]₂ complex shows multi‐step exothermic decomposition patterns. X‐ray powder diffraction parameters or two of the complexes correspond to a tetragonal and orthorhombic crystal lattices. The complexes show fair antifungal activity against Rizoctonia sp., and Stemphylium sp. and moderate antibacterial activity against Clostridium sp., and Pseudomonas sp. The activity increases with increasing concentration of the compounds.

Keywords:

• cobalt(II) and silver(I)
• bimetallic complexes
• polymeric
• bio‐activity
• characterization
• thermal studies

Acknowledgements

The authors thank the Director, Institute of Engineering and Technology, C.S.J.M. University, Kanpur for providing laboratory facilities, the Head, Chemistry Department, Indian Institute of Technology, Kanpur for recording electronic, IR spectra and X‐ray diffraction data, Dr. Nand Lal, Institute of Life Sciences, C.S.J.M. University, Kanpur for his help in biological screening.