Transition metal complexes of a versatile polyalkoxy oxazolidine-based ligand derived from in situ cyclization

Abstract

One-pot reaction between 8-hydroxyquinoline-2-carboxaldehyde (HQC) and tris(hydroxymethyl)aminomethane (TRIS) followed by in situ cyclization yielded an oxazolidine based ligand which produced four mononuclear complexes of Mn^II(1), Co^II(2), Ni^II(3), Zn^II(4), a tetranuclear iron (Fe^III₄) complex (5) and a trinuclear cobalt (Co^IICo^III₂) complex (6). Magnetic studies show dominant antiferromagnetic interaction in tetranuclear iron (Fe^III₄) complex 5 and presence of the slow relaxation of magnetisation in 6. The compounds were also studied for their antibacterial properties. The oxazolidine ligand (H₃L₂) of this study showed good antimicrobial activity not only against Gram-positive bacteria but against Gram-negative bacteria too. The antimicrobial efficacy of the metal complexes (1–6) is also reported.