Oxidation of 2,6-di-tert-butylphenol with tert-butylhydroperoxide catalyzed by cobalt(II) phthalocyanine tetrasulfonate in a methanol-water mixture and formation of an unusual product 4,4′-dihydroxy-3,3′,5,5′-tetra-tert-butylbiphenyl

Cobalt(II) phthalocyanine tetrasulfonate catalyzed oxidation of 2,6-di-tert-butylphenol (●) with tert-butylhydroperoxide in a 80% methanol-water mixture yields predominantly the coupled products 3,3′,5,5′-tetra-tert-butyl-4,4′-diphenoquinone (■) and 4,4′-dihydroxy-3,3′,5,5′-tetra-tert-butylbiphenyl (▴) when the oxidant/substrate ratio was less than 10.