Iridium tetrachloride is an inorganic compound with the approximate formula IrCl<sub>4</sub>(H<sub>2</sub>O)<sub>n</sub>. It is a water-soluble dark brown amorphous solid. A well defined derivative is ammonium hexachloroiridate ((NH<sub>4</sub>)<sub>2</sub>IrCl<sub>6</sub>). It is used to prepare catalysts, such as the Henbest Catalyst for transfer hydrogenation of cyclohexanones.