Mixed ligand complexes of acesulfame/nicotinamide with earth alkaline metal cations MgII, CaII, BaII and SrII : synthesis and characterization

Abstract

I n the scope of this study, acesulfame (ace, acs)-nicotinamide (na) mixed ligand complexes of Mg(II), Ca(II), Sr(II) and Ba(II) were synthesized for the first time. Possible formulas for complexes were determined as [Mg(H2 O)4 (na)2 ](acs)2 , [Ca(H2 O)6 (na)2 ](acs)2 , [Sr(H2 O)7 (na)2 ](acs)2 , [Ba(H2 O)7 (na)2 ](acs)2 ). It was observed that acesulfame ligands within structure were located two moles each at outer surface of coordination sphere acting as counter-ion allowing the charge balance of structure. The solubility of compounds gaining ionic character in this way was determined as quite well as compared to complex structures. Characterizations of complexes synthesized were performed via melting point analysis, elemental analysis, mass spectroscopy and FT-IR spectroscopy methods. Thermal properties of complexes obtained were determined with tandem TG-DTG and DTA techniques. It was found that the coordination spheres of metal cations within compounds obtained in this study were filled with nicotinamide and aqua ligands.