Heterolytic dihydrogen splitting and pK(a) studies of transition metal hydrides:  A density functional study.
Contributors: University of Toronto.  Dept of Chemistry.
Published: 2006
Language: eng
Number of pages: 49
ISBN-13: 9780494163221
Description: DFT calculations were performed on model complexes of MH(NHCMe2 CMe2NH2)(PPh3)2, M = Ru (1), Os (2) to explore the mechanism of catalytic homogeneous hydrogenation of polar bonds using ruthenium based diamine/diphosphine or bisphosphine systems. The ligands PPh3 and 2,3,-diamino-2,3-dimethylbutane were simplified to PH3 and ethylenediamine. Dihydrogen activation by 1 and 2 was found to have five essential steps: free hydrido-amido species and H2(g), approach of H2 to the metal, formation of an eta2-H2  complex, elongation and breaking of the H2 bond, and formation of a trans-dihydride. Two stable conformers exist for the eta2-H 2 complex with osmium, but only one was located with ruthenium. In the presence of alcohol, the activation barrier for the H2-splitting was calculated to be 6 kcal/mol lower.A possible correlation was investigated between the pKalpha THF of 13 acids and the gas-phase proton affinity of their conjugate bases as calculated by DFT methods. A poor correlation was found.
Notes: Source: Masters Abstracts International, Volume: 44-06, page: 2810.

Advisor: Robert Morris

Title on bound thesis: Heterolytic dihydrogen splitting and pK(a) studies of transition metal hydrides: A theoretical study.

Thesis (M.Sc.)--University of Toronto, 2006.

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