Synthesis, crystal structure, and properties of CuL(N-3)H2O

The compound CuL(N-3)(H2O) where L = 1, 15-diaza-3,4:8,9-dibenzo-5,8-trioxa cyclopentadecane-N-acetatic acid has been synthesized and characterized. X- ray crystallography reveals that copper(II) is five-coordinated in a square -pyramidal environment. The complex is a monoclinic system, a= 8.523(3)Angs trom, b=9.844(4)Angstrom c=25.895(9)Angstrom, beta =97.69(3)degrees, V = 21 53.4(3) Angstrom (3), Z = 4, lambda (MoKalpha) = 0.71073, R-W = 0.0757 for 3081 observed reflections [I> 2 sigma (I)]. The copper atom is surrounded b y two nitrogen atoms of the macrocycle, one oxygen atom from the carboxyl g roup in the ligand, one nitrogen atom from the azide group and one oxygen a tom of coordinated water in a distorted square-pyramidal arrangement. The s tability constant (5.8 x 10(6)) of the complex, whose compostion is in the 1:1 metal:ligand molar ratio, was measured by electronic spectra in dimethy l formamide (DMF) as solvent. The EPR spectrum of the complex shows g(perpe ndicular to) = 2.0373 and g(\ \) = 2.250. The results comfirm that the stru cture of the complex is a distorted square pyramid.