The adsorption of Ir2(η-Cl)2(COD)2 (1) (COD = cyclooctadiene) on alumina has been studied by EXAFS at the LIII edge of Ir. The reactions of the surface complex formed upon adsorption of 1, with CO and PPh3 have been investigated by FT-IR spectroscopy. The attachment of 1 on γ-alumina involves the replacement of the bridging chloride ligands by aluminato groups of the support, to form a dimeric surface complex formulated as Ir2(η-O-alumina)2(COD)2. The room temperature reaction of this species with CO gives Ir2(CO)4(η-O-alumina)2. This tetracarbonyl surface species reacts at room temperature with PPh3, to give trans-Ir2(η-O-alumina)2 (CO)2(PPh32. These new surface complexes have considerable potential as precursors for modified iridium-based reforming catalysts. © 1988.
|Journal||Journal of Organometallic Chemistry|
|Publication status||Published - 15 Nov 1988|