NOVEL MONOMERIC AND DIMERIC COPPER(II) PYRIDONE COMPLEXES CONTAINING THE 2,2'-BIPYRIDYL LIGAND

The complexes [{Cu(chp)2(bipy)}2] 1 and [Cu(mhp)2(bipy)] 2 have been prepared (chp = 6-chloro-2-pyridonate, mhp = 6-methyl-2-pyridonate, bipy = 2,2' = bipyridine). Although both are monomeric in solution, 1 is dimeric in the solid state whereas 2 retains its monomeric structure. In the presence of water, 1 reacts to give a monomeric complex, [Cu(chp)2(bipy)(H2O)] 3 which exhibits intramolecular hydrogen bonding. Reaction of 1 with Cu(NO3)2.3H2O leads to partial substitution of the pyridone ligands, forming a second dimeric material, [Cu2(chp)2(bipy)2(H2O)][NO3]2 4. The crystal structures of 1-4 have been determined.