Copper(II) and cobalt(II) complexes based on methyl trifluorosalicylate and bipyridine-type ligands: Synthesis and their antimicrobial activity

Abstract

The synthesis of bis(salicylato)Cu(II) and Co(II) chelates based on methyl trifluorosalicylate and the corresponding M(OAc)2 in the presence of alkali is reported. The following reaction with 2,2′-bipyridine and 1,10-phenanthroline in refluxing methanol affords heteroligand complexes containing methyl trifluorosalicylate and azaheterocyclic ligands in the ratio 2:1. However, the refluxing of Co(II) chelates in ethanol resulted in transesterification of methyl ester group to form heteroligand complexes of ethyl trifluorosalicylate while Cu(II) chelates underwent hydrolysis of ester group to obtain heteroligand complexes of trifluorosalicylic acid. The structures of obtained metal complexes were confirmed by X-Ray diffraction experiment, IR spectroscopy and elemental analysis. The antimycotic and antibacterial activities of synthesized metal complexes were investigated. The heteroligand metal complexes were found to exhibit moderate anti-Candida albicans activity. Among new series of complexes, the most activity showed the mixed metal complexes of trifluorosalicylates and 1,10-phenanthroline revealing a wide range of action in relation to pathogenic fungi and bacteria.