SPECTRAL AND MAGNETIC STUDY OF COPPER(II) MEFANAMATES - CRYSTAL AND MOLECULAR-STRUCTURE OF MATO)DI(N,N-DIETHYLNICOTINAMIDE)DI(AQUA)COPPER(II)

The synthesis and characterization of Cu(II) mefanamate (mef) compound s of composition Cu(mef)(2)L (L = water, caffeine, or methyl-3-pyridyl carbamate) and Cu(mef),L, (L = 3-pyridylcarbinol, nicotinamide, N,N-di ethylnicotinamide, 2,6-dimethanol pyridine or nicotine) is reported. C haracterizations of the compounds were based on elemental analyses, el ectronic, infrared and EPR spectra and magnetic susceptibility measure ments over a temperature range (80-290 K). The spectral and magnetic p roperties of Cu(mef)(2)L indicate the presence of Cu(II) dimers struct urally similar to that of Cu(II) acetate monohydrate. All the Cu(mef)( 2)L-2 compounds possess octahedral stereochemistry about Cu(II) with d iffering tetragonal distortion. An X-ray analysis of Cu(mef)(2)(Et(2)n ia)(2)(H2O)(2) was carried out, and it featured tetragonal bipyramidal geometry around the Cu(II) atom. The tetragonal plane is created by m efanamate anions bonded to the Cu(II) atom via the unidentate carboxyl ate oxygen atoms [Cu-O(2) = 1.936(3)Angstrom] and the pyridine ring ni trogen atoms of the neutral Ligand N,N-diethylnicotinamide [Cu-N(1)= 2 .027(3)Angstrom] in trans-positions. Axial water molecules [Cu-O(4)= 2 .557(3)Angstrom] complete the coordination sphere.