0000000000489788
AUTHOR
Françoise Delbecq
ENANTIOSELECTIVE REDUCTION OF PROCHIRAL KETONES PROMOTED BY AMINO AMIDE RUTHENIUM COMPLEXES: A DFT STUDY
International audience; The origin of enantioselectivity in the reaction of chiral Ru amino amide complexes in the asymmetric transfer hydrogenation of acetophenone was investigated using DFT calculations. For the most stable active catalysts, the full free energy profiles for the reaction were calculated according to the concerted hydrogen transfer mechanism. We succeeded in reproducing the experimentally observed enantioselectivity for the studied Ru amino amide complexes. Our results indicate that the high enantioselectivity can be explained by a stabilizing CH-π interaction existing between the phenyl group of acetophenone and the aromatic substituent of the catalyst, which plays a sign…
Switch in Relative Stability between cis and trans 2-Butene on Pt(111) as a Function of Experimental Conditions: A Density Functional Theory Study
International audience; The adsorption of cis and trans 2-butenes on Pt(111) has been studied as a function of hydrogen coverage OH by means of calculations based on density functional theory (DFT) with the inclusion of dispersion forces. All hydrogen coverages have been considered, from 0 to 1.00 monolayer (ML). For each case, the di-sigma and pi adsorption geometries of the olefins have been compared at a surface coverage of theta(C4H8) = 0.11 ML. Calculations of the Gibbs free energies of these systems have identified the most stable 2-butene isomer (cis or trans) as a function of coverage, temperature, and pressure. In particular, focus was placed on two sets of conditions, namely, one …