91383-65-2Relevant academic research and scientific papers
Mono- and binuclear iridium carbonyl hydrides containing bis(tertiary phosphine) ligands
Fisher, Barbara J.,Eisenberg, Richard
, p. 3216 - 3222 (2008/10/08)
New mono- and binuclear iridium(I) carbonyl halide complexes containing the bis(tertiary phosphine) ligands Ph2P(CH2)nPPh2 (n = 2, dppe; n = 3, dppp) have been prepared, and the formation of iridium(III) hydrides by H2 oxidative addition has been studied. The binuclear complexes [IrX(CO)(dppp)]2 (X = Br, I) possess trans phosphine donors, with the dppp ligands bridging the Ir(I) centers. Addition of H2 yields the tetrahydride species [IrH2X(CO)(dppp)]2 in which the trans phosphine arrangement at each iridium is maintained. However, upon heating, cleavage of the dimers is noted, leading to the mononuclear species IrH2X(CO)(dppp). For X = I, mononuclear dppp complexes are also prepared starting with the reaction of IrI2(CO)2- + dppp under CO to yield IrI(CO)2(dppp). All of the dppe complexes are mononuclear, with dppe acting as a chelate. The necessarily cis disposition of phosphine donors in the mononuclear chelates is readily evidenced by 1H NMR spectroscopy of the hydride complexes. Reversible addition of CO to IrX(CO)(dppe) (X = Br, I) is also observed.
