Hydrogenation of carbon-heteroatom unsaturated bonds: An assessment of consistency of density functional methods

✍ Scribed by Jonas Nyhlén; Timofei Privalov

• Book ID: 103835206
• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 950 KB
• Volume: 324
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/j.molcata.2010.03.001

✦ Synopsis

Hydrogenation of unsaturated carbon-heteroatom bonds, C X, is the general process for which we assess consistency of quantum chemical calculations in the context of B(C 6 F 5 ) 3 -catalyzed reduction of imines with H 2 . According to the mechanism of the reaction, computational uncertainty of energies of hydrogenation of imines, i.e. the difference between results obtained with different methods, contributes to method-related uncertainties of the computed relative energies of key H 2 -activating species. For this reason, it is desirable to know the magnitude of methodological dependence/uncertainty of energies of hydrogenation. Calculations were performed with a number of different density functionals, such as M05-2X, M06-2X, B3LYP, B3PW91, BH&HLYP, MPW1K, MPW1PW91, HCTH407 and PBE, on a number of relevant imines and ketones/aldehydes. Additionally, second-order Møller-Plesset perturbation theory was also evaluated. The results quantitatively reveal the manner in which the form of a method affects the calculated energy change and that there is substantial difference between results obtained with different methods even for structurally simple species.