Dehydrogenation and Diels-Alder reactions in a one-pot synthesis of benzaldehyde from n-butane over acid catalysts

VOx/ZrO2/SiO2 catalysts were synthesized via grafting of vanadium and zirconium alkoxides over Aerosil 380. With these materials the formation of benzaldehyde from butane was possible in a one-pot synthesis, where oxidative dehydrogenation (ODH) for the formation of butadiene is coupled with a Diels-Alder reaction for the formation of benzaldehyde. Experiments performed with a catalyst where the support was modified with Ce instead of Zr, give a material that under the reaction conditions studied does not yield benzaldehyde, showing that acidity plays an important role in the formation of this compound. (C) 2012 Elsevier B.V. All rights reserved.