Heterogenized polymetallic catalysts. Part I. Catalytic air oxidation of 3,5-di- t-butylphenol by Cu(II) and Fe(III) complexed to a polyphenylene polymer containing β-di-and tri-ketone surface ligands

Abstract

Catalysis preparation involves the cyclic trimerization polymerization of acetylated aromatics. The polymer is coated on a high surface area support, Celite, and cured to give insoluble high molecular weight polymer. Reaction of the remaining acetyl end groups with base and methyl acetate gave β-diketone groups on the surface of the polymer. A second reaction with base and methyl acetate places β-triketones on the surface. The β-triketones can bind two metal ions in a known geometry. The chemically modified surfaces containing β-diketone and β-triketone surface ligands were reacted with Cu(OAc) 2 and FeCl 3 to give mono- and bi-metallic surface complexes. The oxidation of 3,5-di- t-butylcatechol was studied with all the surfaces. The monometallic catalysts gave only the ortho-quinone as product. The bimetallic catalysts absorbed about twice as much dioxygen as the monometallic catalysts and gave ring cleaved products. Both gave induction periods before dioxygen uptake began. With the bimetallic catalysts the dioxygen uptake stopped at about the ratio: 2 O 2 1 catechol . This is twice as much dioxygen as that required for ring cleavage so H 2O 2 may be the dioxygen reduction product rather than water. The monomeric Cu(OAc) 2 dioxygen uptake curve reached a maximum and then released gas. This could result from Cu(II) catalyzed decomposition of H 2O 2.