Étude expérimentale et théorique de la cinétique de l'alcoolyse de la liaison P-N extracyclique du 2-diméthylamino-4,4,5,5-tétraméthyl-1,3-dioxaphospholane monocyclique

This work relates to complementarily experimental and theoretical kinetic aspects of the alcoholysis reaction of an extracyclic P-N bond in monocyclic phospholane. A new mechanism was proposed denying the status of the dimethoxyphosphorane awarded to date as reaction intermediate and replaces it with the status of product despite the fact that it disappears when the reaction is studied in the following stoechiometric conditions 1/1. Transition states were optimized at the B3LYP/6-311G (d, p) level and corresponding reaction pathways were determined by plotting energy profiles as a function of the intrinsic reaction coordinate (IRC). A return to the experience has validated the theoretical results and showed that the disappearance of the formed dimethoxyphosphorane is a consequence to a continuous modification of the equilibrium state with methoxyphospholane highlighting the intervention of chemical relaxation during the reaction by 1/1 and its absence in the case of reaction with a large excess of alcohol.