Chloromethylation of aromatic hydrocarbons was a very widely used reaction for well over half a century, both on a laboratory and industrial scale, and has been widely applied in synthesis of a variety of fine or special chemicals such as pharmaceuticals, agrochemicals, dyes, flavors and fragrances, monomers, additives, etc 1-21 . The reaction of aromatic hydrocarbons with hydrochloric acid and trioxane or paraformaldehyde as a formaldehyde precursor gave ...