Coordinated Aqua Ligands Research Articles

Synthesis and characterization of copper(II) coordination compounds with acyclovir: crystal structure of triaquabis [9-{(2-hydroxyethoxy)methyl>guanine] copper(II) nitrate (V) hydrate

The coordination compounds [Cu(acv) 2(H 2O) 3](NO 3) 2·H 2O ( I) (acv = acyclovir) and CuCl 2·acv ( II) have been prepared. Different techniques (IR, electronic reflectance, ESR spectroscopy, thermal analysis, magnetic measurements) have been used to determine the properties of these compounds and also to elucidate the bonding in II. The molecular structure of I has been determined by X-ray crystallography and shows the coordination geometry at copper to be square pyramidal with two acv molecules bound through N-7 in trans basal positions, the other coordination sites being occupied by aqua ligands. The oxygen atom of the carbonyl group is not involved in intramolecular hydrogen bonding to the coordinated aqua ligands. There is a pattern a base-pair recognition between C i symmetrically related molecules. A comparison of the properties of the new compounds ( I and II) with previously isolated [Cu(acv) 2(Cl) 2*H 2O) 2] ( III) is also reported.