Inelastic neutron scattering studies of IrIH{sub 2}(H{sub 2})(PPr{sup 1}{sub 3}){sub 2} and neutron diffraction structure determination of IrIH{sub 2}(H{sub 2}) (PPr{sub 3}{sup 1}){sub 2}-C{sub 10}H{sub 8}. Implications on the mechanism of the interconversion of dihydrogen and hydride ligands
- Los Alamos National Lab., NM (United States)
- Univ. of Hawaii, Honolulu, HA (United States)
- Brookhaven National Lab., Upton, NY (United States)
- National Inst. of Standards and Technology, Gaithersburg, MD (United States)
We have now determined the molecular structure of IrIH{sub 2}(H{sub 2})(PPr{sup i}{sub 3}){sub 2} {center_dot} C{sub 10}H{sub 8} (2{center_dot}C{sub 10}H{sub 8}) through a single-crystal neutron diffraction study and carried out lNS studies on this complex. We report the result of these studies and their implications on the mechanism of dihydrogen/hydride interchange in the IrXH{sub 2}(H{sub 2})(PPr{sup i}{sub 3}){sub 2} complexes. Our results suggest that the interconversion of dihydrogen and hydride ligands in the IrXH{sub 2}(H{sub 2})(PPr{sup i}{sub 3}){sub 2} complexes is coupled to rotation of the dihydrogen ligand. Limbach et al. have proposed that the mechanism of hydride interchange in transition-metal trihydrides involves the rotation of an intermediate dihydrogen ligand. While it is not clear at this point if dihydrogen/hydride interconversion in the IrXH{sub 2}(H{sub 2})(PPr{sup i}{sub 3}){sub 2} complexes involves a bis(dihydrogen) intermediate, our results suggest that this process does not involve initial weakening of the dihydrogen H-H bond. 20 refs., 2 figs., 1 tab.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 91274
- Journal Information:
- Journal of the American Chemical Society, Vol. 117, Issue 27; Other Information: PBD: 12 Jul 1995
- Country of Publication:
- United States
- Language:
- English
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