Synthesis, Isolation, and Characterization of Trisodium Tricarbonyliridate (3-), Na3[Ir(CO)3]. Initial Studies on Its Derivative Chemistry and Structural Characterizations of
文摘
Reduction of Na[Ir(CO)4] by sodium metal in (Me2N)3PO, followed by treatment with liquid ammonia, providedhigh yields (ca. 90%) of unsolvated Na3[Ir(CO)3], a thermally stable, pyrophoric orange solid. This substancecontains iridium in its lowest known formal oxidation state of -3 and has been characterized by IR spectroscopy,elemental analyses, and derivative chemistry, i.e., by its conversion to the triphenylgermyl and triphenylstannylcomplexes, trans-[Ir(CO)3(EPh3)2]-, E = Ge, Sn. Single-crystal X-ray structures of the tetraethylammonium saltsof these species, as well as [Co(CO)3(SnPh3)2]-, confirm the trigonal bipyramidal nature of the anions, originallypredicted on the basis of their IR spectra in the carbonyl stretching frequency region. These structuralcharacterizations provide important additional evidence for the presence of metal tricarbonyl units in Na3[M(CO)3],M = Co, Ir.