SURFACE ORGANOMETALLIC CHEMISTRY - FORMATION OF [IR8(CO)22]2- ON MAGNESIUM-OXIDE

A sample prepared by adsorption of [Ir4(CO)12] on MgO powder was treated in CO at 100-degrees-C and 1 atm, whereupon the surface species was converted to [Ir8(CO)22]2- in high yield. The surface-bound cluster anion was characterized by infrared spectroscopy, and it could be extracted into solution by cation metathesis. The chemistry of the iridium carbonyls on the basic MgO surface in the absence of solvents is similar to the chemistry of the iridium carbonyls in basic solutions. The surface chemistry is an alternative method for preparation of [Ir8(CO)22]2-.