Friedel–Crafts catalysis using supported reagents. Synthesis, characterization, and catalytic application of ZnCl2 supported on sol–gel-derived alumina

Abstract Alumina was synthesized by a sol–gel method using modifying agents such as 2,4-pentanedione, acetophenone, benzophenone, and dibenzoyl methane. The alumina supports were characterized employing N 2 adsorption studies and 27 Al solid-state NMR. The ZnCl 2 /Al 2 O 3 catalysts were made by impregnation of methanolic solution containing calculated amounts of ZnCl 2 on modified alumina supports. The influence of the loading of ZnCl 2 and also the effect of additive used during the sol–gel synthesis of alumina, were probed using Friedel–Crafts alkylation reaction. The alkylation activities indicated the predominance of pore volume in determining the catalytic activities of the catalysts, rather than pore size distribution.