Preparation and characterization of copper(II) coordination compounds with linear chain fatty acids with 7–12 carbon atoms and pyridine. Crystal structure of Cu(O 2CC 8H 17) 2(py) 2(H 2O)

Abstract

Mononuclear compounds of the composition CuX 2(py) 2(H 2O) and binuclear of the composition Cu 2X 4(py) 2 (py = pyridine, X = heptanoate, octanoate, nonanoate, decanoate or dedecanoate) were prepared, analysed and characterized by vibrational spectroscopy and thermogravimetry. Generally, the complexes are unstable, the mononuclear being even less stable than binuclear, losing pyridine in air at room temperature. The X-ray crystal structure of the mononuclear adduct of copper(II) nonanoate with pyridine, Cu(O 2CC 8H 17) 2(py) 2(H 2O), was determined by X-ray diffraction. The copper(II) ion is in a square pyramidal environment with two pyridine nitrogen atoms and two oxygen atoms from unidentate nonaoato ligands forming the basal plane of the pyramid and a water molecule coordinated at the apex. The carboxylate oxygen O(2) is not coordinated to copper, but is bound to water from a neighbouring molecule by the OHO(2) hydrogen bond of 2.691 (5) Å.