Crystal structure of trans-(1,8-dibutyl-1,3,6,8,10,13-hexaazacyclotetradecane-κ4N3,N6,N10,N13)bis(isonicotinato-κO)copper(II) from synchrotron data

The title compound, [Cu(C6H4NO2)2(C16H38N6)] has been synthesized and characterized by structure analysis based on synchrotron data and by FT–IR spectroscopy. The asymmetric unit consists of half of the CuII complex, the other half being completed by inversion symmetry. The CuII ion has a tetragonally distorted octahedral coordination sphere with four secondary N atoms of the azamacrocyclic ligand in the equatorial plane [Cu—Neq = 2.018 (12) Å] and two O atoms of the isonicotinate anions at the axial positions [Cu—Oax = 2.4100 (11) Å]. Intramolecular N—H...O hydrogen bonds between one of the secondary amine N—H groups of the azamacrocyclic ligand and the non-coordinating O atom of the isonicotinate ions stabilize the molecular structure. Intermolecular N—H...N hydrogen bonds between the other macrocyclic N—H group and the pyridine N atom of an adjacent isonicotinate anion as well as π–π interactions [centroid-to-centroid distance 3.711 (2) Å] lead to the formation of rods parallel to [001]