Oxidation of 2,6-di-tert-butylphenol with tert-butyl hydroperoxide catalyzed by iron phthalocyanine tetrasulfonate in a methanol-water mixture

Abstract

The oxidation of 2,6-di-tert-butylphenol (DTBP) with tert-butyl hydroperoxide (Bu'OOH) catalyzed by iron phthalocyanine tetrasulfonate ([FePcTS]) in a 8-to-1 methanol-water mixture resulted with about 70-80% conversion of DTBP in 3 min at ambient temperature. The mole ratios of [FePcTS]:DTBP:Bu'OOH in a typical reaction were 1:400:500, respectively. The major products of the catalysis are the coupled products, namely 3,3',5,5'-tetra-tert-butyl-4,4'-diphenoquinone (DPQ) and 4,4'-dihydroxy-3,3',5,5'-tetra-tert-butylbiphenyl (H(2)DPQ). In addition, the effect of DTBP on the monomer-dimer equilibrium of [FePcTS] and catalytically active [FePcTS] species are discussed