Synthesis, crystal structure and study of the crystal packing in the complex bis(4-aminopyridine-jN1)-dichloridocobalt(II)

摘要

Despite the large number of reported crystalline structures of coordination complexes bearing pyridines as ligands, the relevance of pi-pi interactions among these hereroaromatic systems in the stabilization of their supramolecular structures and properties is not very well documented in the recent literature. The title compound, [CoCl_2(C_5H_6N_2)_2], was obtained as bright-blue crystals suitable for single-crystal X-ray diffraction analysis from the reaction of 4-aminopyridine with cobalt(II) chloride in ethanol. The new complex was fully characterized by a variety of spectroscopic techniques and single-crystal X-ray diffraction. The crystal structure showed a tetrahedral complex stabilized mainly by bidimensional motifs constructed by pi-pi interactions with large horizontal displacements between the 4-aminopyridine units, and N-H ??? Cl hydrogen bonds. Other short contacts, such as C-H ??? Cl interactions, complete the three-dimensional arrangement. The supramolecular investigation was extended by statistical studies using the Cambridge Structural Database and a Hirshfeld surface analysis.