Oxygenation of 1,5-cyclooctadietie (GOD) is achieved on an iridium center using water as a reagent. A :hydrogen-bonding interaction with an unbound nitrogen atom of the naphthyridine-based ligand architecture promotes nucleophilic attack of water to the metal-bound COD: Irida-oxetane and oxo-irida-allyl compounds are,isolated, products which are normally accessed froin reactions with H2O2 or O-2. DFT studies support a ligand-assisted water activation mechanism.