Mechanisms of antioxidant action: antioxidant activity of products derived from o-phenylene phosphites

Abstract

Products known to be formed in the reaction between 4-methyl-2,6-di-t-butylphenyl o-phenylene phosphite (Ic) and cumene hydroperoxide, namely the corresponding phosphate (IIb) and its transformation products (IIa) and (III), are powerful antioxidants in autoxidations catalysed by hydroperoxides and are effective catalysts for the decomposition of cumene hydroperoxide in which they function primarily as Lewis acids. Only (IIa) and (III) satisfy the requirements of the Lewis acid species and although positive identification has not been made a mechanism is proposed involving these species which accounts for the experimental facts.