Synthesis, Spectral Characterization, Molecular Modeling and Antimicrobial Studies of Transition Metal Complexes and the Schiff Base Derived From 3-Formylchromone and Tryptamine

An attempt to find alternative ways of producing polymers from non-petroleum oil specifically, soybean oil, was A series of Cu(II) , Ni(II) , Co(II) , Mn(II) and Zn(II) complexes have been synthesized from the novel schiff base ligand L. The schiff base ligand 3-[(2-(1H-indole-3-yl)ethylimino)methyl]-4H-chromen-4-one (L) has been synthesized by the reaction between chromone-3-carbaldehyde and tryptamine. The nature of bonding and geometry of the transition metal complexes as well as schiff base ligand L have been deduced from elemental analysis, FT-IR, UV-Vis, ¹HNMR, ¹³CNMR, ESR spectral studies, mass, thermal (TGA and DTA) analysis, magnetic susceptibility and molar conductance measurements. All the metal ions are forming 1:1(M:L) metal complexes. Based on elemental, conductance and spectral studies, six-coordinated geometry was assigned for Mn(II) and Co(II) complexes, fourcoordinated geometry was assigned for Cu(II), Ni(II) and Zn(II) complexes. Except cobalt complex remaining four metal ion complexes are neutral in DMSO, cobalt complex is 1:1 electrolyte. The ligand L acts as bidentate and coordinates through nitrogen atom of azomethine group and oxygen atom of keto group of γ-pyrone ring. The 3D molecular modeling and energies of all the compounds are furnished and their analysis for bond length has been carried out for one of the representive complexes. The biological activity of the ligand and its complexes have been studied on E.coli, and Edwardella by well disc and fusion method and found that some of the metal chelates are more active than the free schiff base ligand.