Structure and properties of Cu(II) (o-hydroxypropiophenone-salicylhydrazide)(2,2'-bipyridyl) [Cu(OHP-SHZ)(bipy)] and Cu(II)(o-hydroxypropiophenone-salicylhydrazide) (2,2'-bipyridylamine) monohydrate [Cu(OHP-SHZ)(bipyam)H2O

The preparation of stable Lewis base adducts of Cut (H(2)L = Schiff base derived from the condensation of o-hydroxypropiophenone (OHP) and salicylhydrazide (SHZ)) is described. The N-donors bipy and bipyam ligands (bipy = 2,2'-bipyridyl; bipyam = 2,2'-bipyridylamine) give the complexes [Cu(OHP-SHZ)(bipy)] (I) and [Cu(OHP-SHZ) (bipyam)]H2O (II) which have been characterized by physical and spectroscopic techniques. Crystals of I are orthorhombic, space group Pcab, with a = 10.221(3), b = 12.643(3), c = 35.148(3) Angstrom, V = 4581(2) Angstrom(3) and Z = 8, The structure of complex I is shown to comprise discrete monomeric [Cu(OHP-SHZ)(bipy)] molecules in which the Cu(II) atom environment exhibits a highly distorted five-coordinated geometry. Crystals of II are monoclinic, space group C2/c, with a = 24.804(3), b = 13.231(3), c = 14.739(3) Angstrom, beta = 99.57(2)degrees, V = 4770(2) Angstrom(3) and Z = 8. The structure of this complex consists of discrete entities associated into H-bonded binuclear units via the lattice water molecules. The coordination sphere around the copper center is nearly square pyramidal. The transition from a six-membered chelated ring to a five-membered one results in a less distorted coordination polyhedron around the Cu(II) ion, In both complexes the OHP-SHZ ligand occupies three of the coordination sites through the same (ONO) donor atoms while the remaining positions are occupied by the pyridine N atoms. EPR spectra provide evidence of the existence of very weak magnetic exchange coupling in the complex [Cu(OHP-SHZ) (bipyam)] H2O (II), Thermogravimetric and differential scanning calorimetric studies of complex I show that this complex loses the bipy molecule through an endothermic process with Delta H = 81.75 kJ mol(-1). The best kinetic parameter values corresponding to the process involving the loss of the bipy molecule were found on the basis of the agreement between non-isothermal and isothermal methods and are given by the Abou-Shaaban-Simonelli education in isothermal conditions. The better representation of the reaction mechanism is the phase-boundary, spherical symmetry reaction.