One-Step Conversion of Methyl Ketones to Acyl Chlorides

Treatment of aromatic and heteroaromatic methyl ketones with sulfur monochloride and catalytic amounts of pyridine in refluxing chlorobenzene leads to the formation of acyl chlorides. Both electron-rich and electron-poor aryl methyl ketones can be used as starting materials. The resulting C₁-byproduct depends on the precise reaction conditions chosen.