Synthesis, Characterization and Antimicrobial evaluation of some mixed ligand chelates using 2-aminobenzoic acid as a secondary ligand

Abstract

The present work deals with the preparation of four mixed ligand chelates that resulted from the reaction of Schiff base[coupling of 2-hydroxyacetophenone and 2,4-dinitrophenylhydrazine (HL1) and 2-aminobenzoic acid (L2)]. The Schiff base, 2-aminobenzoic acid and their mixed ligand chelates were offered to several physicochemical tools; CHN elemental analyses, molar conductivity, magnetic moments, thermogravimetric analysis, IR and ¹HNMR, Basis on the obtained results, the mixed ligand chelates appeared in the 1:1:1 [M:L1:L2] ratio as found from the elemental analysis data and found to have the formulae [L1ML2(H₂O)₂], where M = Mn(II), Co(II) and Ni(II) ions and [L1FeL2(ONO₂)(H₂O)], Meanwhile, the 1:1:2[M:L1:L2] ratio is for  [L1Cr(L2)₂] complex, The molar conductance results revealed that the mixed ligand chelates were non-electrolytes, whereas, the magnetic moments were used to confirm the coordinating capacity of the ligands, infrared spectra displayed that the Schiff base, 2-aminobenzoic acid were bonded to the metal ions in a bidentate manner with donor sites. According to the results obtained from the electronic spectra,  an octahedral structure was suggested for all the chelates. Also, the hydrated and coordinated water molecules were discussed using thermogravimetric analysis. Antimicrobial activities of the prepared compounds were tested on several types of bacteria and fungi and their activities were reported.