Computational studies of nucleophilic attack and protonation of electron-deficient benzoheterocycle triosmium clusters.
The density functional theory method has been applied to gain insights into the regioselectivity of nucleophilic attack and protonation of electron-deficient benzoheterocycle triosmium clusters. We report our computational results on the reaction of the green 46-electron triosmium clusters Os3(CO)(9)(mu3-eta2-(LH))(mu-H) (L = benzoxazole, 1a; benzothiazole, 1b; dihydroquinoline, 1c; 1,3-dehydroindoline, 1d; 4H-3,1-benzoxazine, 1e) with hydride (H-) and proton (H+) in order to elucidate factors affecting the observed differences in the structure of the kinetic products of these reactions. Transition-state calculations for the interconversion of the anionic tautomers resulting from H- attack on the clusters 1a-e show that the activation energies of these anionic clusters are considerably lower than the previously reported barriers for related neutral clusters. Calculations also reveal that the structures of the kinetic products resulting from sequential H-/H+ attack are determined by the protonation process.
Nowroozi-Isfahani
Taraneh
T
Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, USA.
Musaev
Djamaladdin G
DG
Morokuma
Keiji
K
Rosenberg
Edward
E