Density functional theory investigations on acid-catalysed epoxide oxidative ring-opening by DMSO. Competition between oxidation processes

DFT investigations of the acid-catalysed oxidation of linear and cyclic epoxides by DMSO revealed that a first step of nucleophilic ring-opening is followed by two different reaction pathways: on one hand α-hydroxycarbonyl derivatives are formed, via oxidative ring-opening, and on the other hand two aldehyde moieties are obtained, via oxidative cleavage. Calculations with the polarized continuum method (PCM) taking into account the DMSO solvation effect did not significantly change the energy barriers.