Design of a solid catalyst for the synthesis of a molecule with blossom orange scent

The synthesis of 2-methyl-2-naphthyl-4-methyl-1,3-dioxolane, a compound with blossom orange scent, has been successfully carried out by acetalization reaction between methyl naphthyl ketone and propylene glycol using different acid solid catalysts. The size and polarity of reactants, intermediates and product determine the strong influence of the textural properties of the catalyst (crystal size, acidity and adsorption properties) with the large pore tridirectional zeolites (Y and Beta) being the most active. It has been found that the hydrophobicity of the catalyst can be more determinant than the number of active sites present in the catalyst. The results show an optimum in activity for Si/Al ratios in Y and Beta zeolites that correspond to 35 and 100, respectively.