Supramolecular interaction in copper(ll) complexes containing schiff base ligands Phailyn Khemthong1, Chatphorn Theppitak1, Filip Kielar1 and Kittipong Chainok2

  • Chatphorn Theppitak
Keywords: Copper(II), Noncovalent interactions, Schiff base, Supramolecule, X-ray crystallography


Two new dinuclear copper(II) complexes containing 4-bromo-N-(2-pyridylmethylene)aniline (C12H9BrN2) or 4-chloro-3,5-dimethyl-N-(2-pyridylmethylene)aniline (C14H13ClN2) Schiff base ligands, [Cu(C12H9BrN2)Cl2] (1) or [Cu(C14H13ClN2)Cl2] (2), were synthesized. Single crystal X-ray analysis at room temperature revealed that complex 1 crystallizes in the monoclinic space group P21/n and the molecular structure consists of a dichloro-bridged dinuclear Cu(II) species [Cu···Cu = 3.4678(6) Å]. Whereas, complex 2 also crystallizes the monoclinic system with P21/c space group in which the two Cu(II) atoms are linked by weak electrostatic Cu···Cl interactions [3.021(1) Å] to form a dinuclear complex [Cu···Cu separation = 3.468(1) Å]. The different of supramolecular artchitecture of complexes is the result of combination of intermolecular forces including electrostatic Cu···Cl, halogen···π, π–π, C–H···π and C–H···Cl interactions.


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