Synthesis and structure of an adduct of copper(II) nitrate with 1-(3-Methyl-1-phenyl-2-pyrazolin-5-onylidene-4)-3,3-dimethyl-1,2,3, 4-tetrahydroisoquinoline

The adduct [Cu(H2O)2(NO3) 2]·2L (I, L = 1-(3-methyl-1-phenyl-2-pyrazolin-5-onylidene-4)- 3,3-dimethyl-1,2,3,4-tetrahydroisoquinoline) was studied by X-ray diffraction and IR and electronic absorption spectroscopies. Compound I is formed during the reaction of copper(II) nitrate hydrate with L in acetonitrile. The structure of I is composed of chains formed by [Cu(H2O)2(NO 3)2] complexes and L molecules linked by hydrogen bonds. The square coordination environment about the Cu atom consists of two oxygen atoms of water molecules and two oxygen atoms of monodentate terminal nitrato groups (Cu-O(NO3) = 1.947(4) Å, Cu-O(H2O) = 1.870(4) Å). The plane of the nitrato group is nearly perpendicular to the coordination square. There is an additional interaction of the copper atom with the second oxygen atom of the nitrato group (Cu-O = 2.627(4) Å). Molecules L are in the enamineketone isomeric form with an intramolecular H-bond that closes the six-membered H-ring.