Crystal structure of a mononuclear copper(II) complex with 2-methoxy-N,N-bis­(quinolin-2-yl­meth­yl)­ethyl­amine (DQMEA)

Structural characterization of the compound [Cu(C(2)H(3)N)(C(23)H(23)N(3)O)](ClO(4))(2)] or [Cu(C(2)H(3)N)(DQMEA)](ClO(4))(2)] [DQMEA = 2-methoxy-N,N-bis­(quinolin-2-ylmeth­yl)ethyl­amine] {systematic name: (aceto­nitrile)[2-methoxy-N,N-bis(quinolin-2-ylmeth­yl)ethyl­amine]­copper(II) diperchlorate} by single-crystal X-ray diffraction reveals a complex cation with a tetra­dentate coordination of the DQMEA ligand along with monodentate coordination of a CH(3)CN ligand to a single Cu(II) center, with two perchlorate anions providing charge balance. The Cu(II) center has a distorted square-pyramidal geometry in which the nitro­gen atoms of the DQMEA and CH(3)CN ligands occupy the equatorial positions, while the oxygen atom of the DQMEA ligand resides in the axial position with an elongated Cu—O bond. The quinoline ring systems are nearly co-planar in the structure, while the linear CH(3)CN ligand is tilted significantly below this plane, and the central nitro­gen of DQMEA is above it. Within the complex, weak C—H⋯N hydrogen bonding takes place between the nitro­gen of CH(3)CN and a neighboring quinolyl group. The perchlorate ions are disordered within the structure, but undergo a number of weak inter­molecular C—H⋯O hydrogen-bonding inter­actions. Additional weak π-stacking inter­actions between the quinolyl groups of neighboring complexes further stabilize the crystal packing.