Crystal structure of a copper stabilized hydrate of di-2-pyridyl ketone

The addition of a yellow ethanolic solution of di-2-pyridyl ketone to a blue-green aqueous solution of copper(II) bromide produces an exothermic reaction and a brilliant purple solution. Brilliant purple single crystals were obtained from the solution by solvent evaporation and were subjected to a crystal structure determination. The structure of the isolated gem-diol compound stabilized by a transition metal contains two di(2-pyridyl)methanediol ligands bonded to the central copper atom in a distorted octahedral arrangement providing four nitrogen atoms at relatively short bond distances and two oxygen atoms at longer bond distances. In the solid state, both oxygen atoms on each of the gem-diol ligands are protonated. (C) 2000 Elsevier Science Ltd All rights reserved.