Solvent-induced formation of two novel mononuclear and dinuclear copper(II) complexes: Synthesis, structure and properties

Two new complexes, [Cu(L)2(CH3COO)2(H2O)] · 6H2O (1) and [Cu2(L)2(CH3COO)4] · 2C2H5OH (2) (where Ldouble bond; length as m-dashN-(4-chlorophenyl)-3-pyridinecarboxamide), have been synthesized by altering the solvent of reaction system. For 1, the mononuclear complex is extended into a 3D supramolecular architecture through intricate non-covalent interactions. Unexpectedly, two scarcely reported cyclic water tetramers with C2h and D2h symmetries simultaneously exist in a 1D water chain. Whereas the dinuclear complex 2 represents a 2D framework by double hydrogen bonds with solvent ethanol molecules and π–π stacking interactions. In addition, the luminescent properties of them are also discussed.