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

ZnCl2-aluminosilicate catalysts were prepared via a sol-gel route involving fluoride-catalyzed hydrolysis of aluminum and silicon alkoxides in the pre sence of NaF, KF, NH4F and ZnF2. The catalysts were characterized by employ ing Si-29, Al-27 and F-19 solid-state MAS NMR. The dependence of the activi ties of the catalysts on the nature and amount of fluoride present in the c atalysts were investigated using Friedel-Crafts alkylation reaction of benz ene with benzyl chloride.