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Four niobium phosphate samples obtained by different methods were tested in the alkylation of anisole with benzyl alcohol. The catalysts were characterized by XRD, N2 adsorption and FTIR in the structural and adsorbed pyridine regions. The microporous niobium phosphate presented the highest activity and satisfactory selectivity to alkylated products. The good performance of this microporous material in the alkylation reaction, a first time result, may be mainly attributed to the large amount of Bronsted acid sites on the large surface area.

The catalytic activity of niobium phosphate was evaluated in the benzylation reaction of the anisole with benzyl alcohol, 2-phenyl-ethanol and 1-phenyl-ethanol, in liquid phase. The influence of concentration of the catalysts was evaluated. The niobium phosphate was characterized by DRX, thermogravimetry analysis, BET surface area and IV-pyridine. We found high activities (100%) and selectivity (>90%) in the benzylation with benzyl alcohol and 1-phenyl-ethanol. No result was obtained with 2-phenyl-ethanol. In the reaction with benzyl alcohol a side reaction occurs to form dibenzylether. It has been concluded that Lewis acid sites are responsible for the ether formation and Bronsted acid sites (POH and NbOH) are responsible for the benzylation of anisole with alcohols. The isomer composition in benzylation products from anisole alkylation gave predominantly ortho – para substitution in accordance with a typical eletrophilic aromatic substitution pathway.