Catalytic oxidation by Fe- and Cu-doped

P. VILLABRILLE; G. ROMANELLI; L. GASSA; C. CÁCERES; P. VÁZQUEZ

Texas

Conferencia; 20th North American Meeting of the Catalysis Society; 2007

Because of their excellent characteristics, bulk heteropolyacids with Kegginstructure (HPA) and their salts are widely used in industrial catalysis [1]. Heteropolyacidshaving mixed addenda atoms such as V and Mo are attractive for the molecular design. It isimportant to mention that the polyanion structures are maintained at low-temperature reactions.On the other hand, it is important to emphasize that the quinone derivatives play an importantrole in biosystems. Natural products having a benzoquinone structure show biologicallyimportant properties such as cardiovascular, antitumoral, antibacterial, antigerminative andantiprotozoan activities. Furthermore, benzoquinones are useful fine chemicals in organicindustry. For example, 2,3,5-trimethyl-1,4-benzoquinone is a key intermediate in theproduction of Vitamin E [2]. In the present paper, we report the preparation of Fe- and CudopedKeggin heteropolyacids where one Mo was substituted by one V, and theircharacterization by means of FT-IR,31P-NMR, DRS, XRD, thermal analysis, potentiometrictitration, and electrochemical measurements. In addition, the activity of the synthesizedcatalysts for the oxidation reaction 2,6-dimethylphenol to 2,6-dimethyl-1,4-benzoquinone(Scheme 1), using H2O2 as oxidant at room temperature, was tested.