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As one of the most important reactions in aromatic substitution chemistry, the Friedel-Crafts reaction (1) received extensive coverage in sophomore organic chemistry. The most widely employed Lewis acid for the Friedel-Crafts reaction is aluminum chloride, although several other reagents also have appreciable reactivity (I). The safety and handling problems of aluminum chloride in the sophomore organic laboratory are not easily addressed and prompted us to examine iron(III) chloride as an alternative Lewis acid for the Friedel-Crafts acylation reaction. Previous studies have demonstrated that anhydrous iron(III) chloride is an effective catalyst for the Friedel-Crafts alkylation of biphenyl (2) and benzene (3) with tert-butyl chloride. We have found that iron(III) chloride serves admirably in the place of aluminum chloride for several Friedel-Crafts acylation reactions currently described in the literature ). For example, the Friedel-Crafts acylation of anisole, toluene, p-xylene, and biphenyl with acetyl chloride employing FeCl sub 3 gave the corresponding ketones in slightly lower yields (by 10-15%) than the reactions employing AlCl sub 3 under identical conditions. Despite the hygroscopic and mildly corrosive nature of anhydrous iron(III) chloride, the handling and work-up procedures were simpler and readily...