Synthesis and Crystal Structure of poly[bis(1-ethyl-2,5-dihydro-1H-imidazole-κN3)(succinato-κO)copper(II)]

Abstract

The new title copper(II) succinato complex [Cu(O2C(CH2)2CO2)(C3H5N2C2H5)2]n (1) has been isolated as single crystals state from one pot reaction between HO2C(CH2)2CO2H (succinic acid), C3H5N2C2H5 (1-ethyl-2,5-dihydro-1H-imidazole) and Cu(CH3COO)2 in distilled water. Compound 1 has been characterized by elemental analysis, FTIR spectroscopy and X-ray diffraction. In the solid state, 1 crystallizes in the orthorhombic chiral system P212121 space group with a = 9.8406(3) Å, b = 12.6318(3) Å, c = 13.0246(4) Å, a = b = g = 90°, V = 1619.016 Å3 and Z = 4. The asymmetric unit of the copper(II) complex is formed by one central copper(II), two imidazole molecules and one succinate unit. The copper(II) ion is tetra-coordinated by two nitrogen atoms from imidazole molecules acting in η1-mode, one oxygen atom from succinate anion and one oxygen atom from succinate anion of a neighboring molecule complex. In the structure the copper(II) cation is situated in N2O2 inner, and its environment is best described as square planar geometry. Each arm of the succinate anions acts in η1-mode, and the succinate units act as bridge between two copper(II) centers developing a polymer coordination. In the crystal, unclassical hydrogen bonds of type C—H···O involving the coordinated and the non-coordinated oxygen atoms of the succinate groups as donor atoms, generate a supramolecular network. The overall structure consists of parallel infinite chains of Cu(C4O4H4)(C3H5N2C2H5)2, each parallel chain extending along the b axis.