A molecular electron density theory study of the mechanism, chemo- and stereoselectivity of the epoxidation reaction of R-carvone with peracetic acid

The epoxidation reaction of R-carvone 8 with peracetic acid 9 has been studied within the molecular
electron density theory at the B3LYP/6-311(d,p) computational level. The chemo- and stereoisomeric
reaction paths involving the two C–C double bonds of R-carvone 8 have been studied. DFT calculations
account for the high chemoselectivity involving the C–C double bond of the isopropenyl group and the
low diastereoselectivity, in complete agreement with the experimental outcomes. The Baeyer–Villiger
reaction involving the carbonyl group of R-carvone 8 has also been analysed. A bonding evolution
theory analysis of the epoxidation reaction shows the complexity of the bonding changes taking place
along this reaction. Formation of the oxirane ring takes place asynchronously at the end of the reaction
by attack of anionic oxygen on the two carbons of the isopropenyl C–C double bond.