Liquid-phase selective oxidation of 2-methylnaphtalene to the vitamin K-3 was investigated on a series of mesostructured vanadia-alumina catalysts with different V/Al ratios (0.1-1). They were prepared by the co-precipitation of ammonium metavanadate and aluminum nitrate at pH 5 and characterized by XRD, Raman, TG-DTA, elemental analysis and adsorption-desorption isotherms of nitrogen at -196 degrees C. The influence of the catalyst composition and calcination temperature upon the physico-chemical properties were closely investigated in relation with the catalytic performances. The result of this investigation indicated the catalysts containing a higher vanadium loading and calcined at 300 C as the most active. Thus, the VAl07 catalyst led to a selectivity in vitamin K-3 of 54% for a conversion of 2-methylnaphtalene of 76%. Such an activity corresponded to mixtures where metavanadate (Raman line at 940 cm-1) and decavanadate (Raman line at 990 cm(-1)) species were the most abundant. No lines of V2O5 (around 705 cm(-1)) were detected in the catalysts calcined below 600 degrees C. 2015 Elsevier B.V. All rights reserved.