Azomethine imines of pyrazolidone series and their bis-chelate Ni(II), Zn(II), Cd(II) complexes. Quantum chemical simulation

Prototropic processes in the molecules of azomethine imines with 2-pyrrolylmethylidene fragment were studied by the density functional theory (DFT) method and the most stable by energy isomers with the intramolecular hydrogen bond between the nitrogen atoms of the pyrrole and the pyrazole rings were found. The energy barriers of the reactions of intramolecular proton transfer were estimated. Based on quantum chemical calculations of the molecular structure of azomethine imine bis-chelates ML2 [M = Ni(II), Zn(II), Cd(II)] with the coordination unit MN2N2 the most stable configurations of the complexes were determined.