Reactions of Phenylethylenes with O(3P) Atoms in Condensed Phases

Article abstract of DOI:10.1021/jo00379a013

Oxidation of styrene, α- and β-alkyl-substituted styrenes, cis- and trans-stilbene, triphenylethylene, allylbenzene, and its trans β-alkyl-substituted derivatives with O(3P) resulted mainly in epoxides and carbonyl compounds formed by 1,2-H shifts.The O(3P) atoms were produced by microwave discharge of O2, CO2, or N2O/N2 in the presence of He.The temperature effect on the relative yields of products was studied on cis-stilbene and the regioselectivity of the O(3P) attack on the double bond in the series of β-alkylstyrenes and β-alkyl-substituted allylbenzenes.The mechanism of the oxidation is postulated to involve a diradical intermediate.The temperature effect is explained by the interconversion of different electronic states of this diradical and the steric effect by an early unsymmetric transition state for the addition of O(3P) atoms to the double bond.