Spectral study of copper(II) flufenamates: crystal and molecular structure of biis(Flufenamato)DI(N,N-diethylnicotinamide)Di(Aqua)copper(II)
摘要:
New copper(II) flufenamate (flu) compounds of the composition Cu(flu)(2)L (L = papaverine or caffeine) and Cu(flu)(2)L(2) [L = nicotine, nicotinamide, N,N-diethylnicotinamide (Et(2)nia), pyridine-2,6-dimethanol or methyl-3-pyridylcarbamate] have been prepared. The spectroscopic properties of Cu(flu)(2)L indicate the presence of copper(II) dimers structurally similar to those in copper(II) acetate monohydrate. All the Cu(flu)(2)L(2) compounds seem to possess octahedral copper(II) stereochemistry with differing tetragonal distortions. An X-ray analysis of Cu(flu)(2)(Et(2)nia)(2)(H2O)(2) was carried out, and it featured tetragonal bipyramidal geometry around the copper(II) atom. The tetragonal plane is created by flufenamate anions bonded to the copper(II) atom via the unidentate carboxylate oxygen atoms [Cu-O(3) = 196.1(2) pm], the pyridine ring nitrogen atoms of the neutral ligand N,N-diethylnicotinamide [Cu-N(1) = 200.1(3) pm] and axial water molecules [Cu-O(2) = 244.9(4) pm].