Bis{2-[2-(isopropylammonio)ethyliminomethyl]-5-methoxyphenolato}copper(II) bis(perchlorate)

In the title compound, [Cu(C13H20N2O2)2](ClO4)2, the CuII atom in the complex dication is chelated by two phenolate O atoms and two imine N atoms from two zwitterionic 2-[2-(isopropylammonio)ethyliminomethyl]-5-methoxyphenolate ligands, forming a distorted square-planar geometry. One of the perchlorate anions is disordered over two sites with occupancies of 0.611 (15) and 0.389 (15). Intramolecular N—H⋯O hydrogen bonds are observed in the complex dication. In the crystal structure, the perchlorate anions are linked to complex dications by intermolecular N—H⋯O hydrogen bonds.

In the title compound, [Cu(C 13 H 20 N 2 O 2 ) 2 ](ClO 4 ) 2 , the Cu II atom in the complex dication is chelated by two phenolate O atoms and two imine N atoms from two zwitterionic 2-[2-(isopropylammonio)ethyliminomethyl]-5-methoxyphenolate ligands, forming a distorted square-planar geometry. One of the perchlorate anions is disordered over two sites with occupancies of 0.611 (15) and 0.389 (15). Intramolecular N-HÁ Á ÁO hydrogen bonds are observed in the complex dication. In the crystal structure, the perchlorate anions are linked to complex dications by intermolecular N-HÁ Á ÁO hydrogen bonds.

Experimental
Crystal data [Cu(C 13 Table 1 Selected bond lengths (Å ).  Hydrogen-bond geometry (Å , ).  (Collinson & Fenton, 1996;Hossain et al., 1996;Tarafder et al., 2002;Musie et al., 2003;García-Raso et al., 2003). Considerable effort has been made to construct a variety of copper(II) complexes in an attempt to model the physical and chemical behaviour of copper-containing metalloenzymes (Reddy et al., 2000). The peculiarity of copper lies in its ability to form complexes with coordination number four, five, and six (Ray et al., 2003;Arnold et al., 2003;Raptopoulou et al., 1998). As part of our investigations into novel urease inhibitors (Wang et al., 2009a(Wang et al., ,b,2010Wang, 2009), the title compound, a new Cu II complex, has been synthesized, and its crystal structure is reported here.
The asymmetric units contains one mononuclear copper(II) complex dication, and two perchlorate anions ( Fig.   1). The Cu II atom in the dication is chelated by two phenolate O atoms and two imine N atoms from two 2-[(2isopropylammonioethylimino)methyl]-5-methoxyphenolate ligands, forming a square-planar geometry. The coordinate bond lengths (Table 1) and angles are typical and are comparable with those observed in other related copper(II) complexes (Hebbachi & Benali-Cherif, 2005;Butcher et al., 2003;Elmali et al., 2000;Warda et al., 1997). There are two intramolecular N-H···O hydrogen bonds in the complex dication.
In the crystal structure, the perchlorate anions are linked to the complex dications by intermolecular N-H···O hydrogen bonds (Table 2   (1.0 mmol, 370 mg) were dissolved in methanol (80 ml). The mixture was stirred at room temperature for about 1 h to give a blue solution. After keeping the solution in air for a few days, blue block-like crystals were formed.

Refinement
H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with C-H distances of 0.93-0.98 Å, N-H distances of 0.90 Å, and with U iso (H) set at 1.2U eq (C,N) and 1.5U eq (C methyl ). One of the perchlorate anions is disordered over two distinct sites with occupancies of 0.611 (15) and 0.389 (15). The positional and U ij parameters of disordered atoms Cl2 and Cl2' were constrained to be the same. The Cl···O and O···O distances in the disorder components were restrained to 1.42 (1) and 2.35 (2) Å, respectively. The U ij parameters of disordered O atoms were restrained to an approximate isotropic behaviour. The C10-C11 and C10-C12 distances were restrained to 1.540 (8) Å.