178180-83-1Relevant articles and documents
Reactivity and selectivity in the oxidation of styrene derivatives, II studies on the oxidation of p-substituted α-methylstyrenes
Suprun, Wladimir
, p. 231 - 237 (1996)
The liquid phase oxidation of p-substituted (Br-, Cl-, t-Bu-, MeO-, CF3-) α-methylstyrenes and of α,p-dimethoxystyrene with pure oxygen was investigated in chlorobenzene solution and in presence of cumene and of cumene hydroperoxide in the temperature range 65-125°C. The product yields were determined gaschromatographically. The differences of the activation energies of the epoxide formation and the parallel reactions amount to 19-48 kJ/mol. The epoxide selectivity increases with increasing temperature and concentration of olefine. The relative chain propagation constants kp (C=C) were determined by competitive oxidation with cumene. The kp(C=C) values of p-substituted α-methylstyrenes can be correlated by the Hammett equation with both σ and σ+ substituent constants.