ratios were prepared by co-precipitation in super-saturated conditions, followed by thermal decomposition at 500°C. The synthesized materials were evaluated as catalysts for the self-condensation of octanal in order to establish structure-tofunctionality properties of the prepared materials. The presence of zinc affects the structural and textural properties of the as-synthesized hydrotalcites and derived mixed oxides, and provokes a remarkable modification on the acidicbasic properties of the materials as studied by CO 2 and NH 3 -TPD. The presence of Zn 2? caused an increment in the concentration of surface acidic sites compared to the binary Mg-Al system. The samples characterized by a Zn/Mg ratio B1 showed the optimal ratio of acidic and basic sites and the best catalytic performance for the production of the a,b-unsaturated aldehyde. The reconstruction of the layered materials (starting from the mixed oxides) caused an increment in the concentration of surface OH -groups, further modifying the selectivity of the reaction.

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