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

The oxidation of 2,6-di- tert -butylphenol (DTBP) with tert -butyl hydroperoxide (Bu t 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 t 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.