Reactions of 2-acetylpyridine aminoguanidine with Cu(II) under different reaction conditions

Aminoguanidine derivatives are the focus of research because of their various biological activities, such as antiviral, antibacterial, analgesic, antioxidant, and anticancer. Their complexes with different metals are also examined and many of them show significant biological activity, too. Besides, some of the complexes show good photoluminescent properties and are used for the preparation of photoelectronic devices. In accordance, the synthesis, physicochemical, structural, and thermal characterization of the complexes of 2-acetylpyridine aminoguanidine (L) with copper(II) is described here. Under different reaction conditions, Cu(II) with L gives three complexes of different compositions. By varying the strength of basicity of the deprotonating agent used, it was proven here that the Schiff base could be coordinated in neutral or monoanionic form. In the presence of pyridine, a coordination polymer is obtained, while in the presence of ammonia/lithium acetate two different monomeric complexes were crystallized. Their physicochemical and thermal properties, as well as molecular and crystal structure, are determined.