DFT study of an inner-sphere mechanism in the hydrogen transfer from a hydroxycyclopentadienyl ruthenium hydride to imines.
2007 (English)In: Organometallics, ISSN 0276-7333, E-ISSN 1520-6041, Vol. 26, no 11, 2840-2848 p.Article in journal (Refereed) Published
A combination of the DFT method with the computational description of environmental effects by solvent was applied to a theor. study of the H transfer to imines by [2,3,4,5-Ph4(Î·5-C4COH)Ru(CO)2H] (2) within a mol. model that closely mimics the authentic reaction conditions. A consistent polarizable continuum solvent model (PCM) was instrumental and necessary in achieving stability of the computational model. Environmental effects by solvent were also considered in an extended model with an addn. of explicit solvent mols. within the PCM. The study elucidates an inner-sphere mechanism. Intermediate complexes and transition states were characterized. Three distinct energy barriers along the reaction coordinate are predicted when solvent effects are taken into account. The imine coordinates to Ru via ring slippage with an energy barrier of âˆŒ15 kcal/mol. Close in energy (12 kcal/mol) is the transition state of the hydride transfer, which gives an (Î·2-cyclopentadienone)ruthenium amine intermediate. The presence of Ph groups on the Cp ring facilitates the ring slippage that occurs on imine coordination. This Î·2-intermediate finally rearranges to the corresponding (Î·4-cyclopentadienone)ruthenium amine complex via a transition state at 9 kcal/mol. The stable Ru amine complex was verified against an x-ray structure of the corresponding complex. Inclusion of the solvent (by PCM or explicit mols.) was required to stabilize low-hapticity intermediates and transition state structures. [on SciFinder(R)]
Place, publisher, year, edition, pages
2007. Vol. 26, no 11, 2840-2848 p.
ruthenium hydroxycyclopentadienyl hydride hydrogen transfer imine DFT potential barrier, transition state structure ruthenium hydride hydrogen transfer imine DFT, solvent effect ruthenium hydride hydrogen transfer imine DFT, Amine complex ruthenium hydride hydrogen transfer imine DFT
IdentifiersURN: urn:nbn:se:uu:diva-174516DOI: 10.1021/om070169mOAI: oai:DiVA.org:uu-174516DiVA: diva2:527603
CAPLUS AN 2007:466677(Journal)2012-05-212012-05-212012-05-21