Polynuclear iridium hydrides

Reviews during late 1988 and 1989 relevant to metal-hydrides include a treatment of H2 oxidative addition and dihydride transfer reactions involving [Ir(X)(CO)L2]. Stereochemical aspects are emphasized. A discussion of polynuclear iridium hydrides has also appeared. The relative bond strengths of M—H... 

Unlike cobalt and rhodium, the chemistry of polynuclear iridium carbonyl derivatives has not been studied in detail (15a). Reduction of Ir4(CO)i2 under carbon monoxide with K2C03 in methanol gives the yellow tetranuclear hydride derivative [Ir4(CO)nH], whereas under nitrogen the brown dianion [Ir8(CO)2o]2- has been isolated as a tetraalkylam-monium salt (97). It has been suggested that the structure of the dianion could result from the linking of two iridium tetrahedra, although its formulation so far is based only on elemental analyses. Clearly such an interesting compound deserves further chemical and structural characterization. 

Hydride Complexes of Ruthenium, Rhodium, and Iridium G. L. Geoffroy and J. R. Lehman Structures and Physical Properties of Polynuclear Carboxylates Janet Catterick and Peter Thornton... 

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