The preparation, physical and chemical properties, and applications on mono‐, di‐, tri‐, tetra‐, and pentachlorotoluenes are reviewed. Reactions of chlorotoluenes are classified into those involving the aromatic ring, the methyl group, and the halogen. The reactions involving the methyl group are widely used to synthesize a variety of functionalized chloroaromatic compounds. Some of the recent applications of these compounds are based on replacement of the halogen by other functional groups catalyzed by transition‐metal compounds. Monochlorotoluenes are obtained generally by reaction of toluene with chlorine under a variety of homogeneous and heterogeneous conditions. The higher chlorotoluenes are obtained usually by chlorination of the lower chlorinated analogues. Many detailed studies have been conducted to evaluate the toxicological properties of chlorotoluenes. Ring‐chlorinated toluenes find principal applications in the pesticide, pharmaceutical, peroxide, dye, and other industries.
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‐Chlorotoluene is an especially valuable starting material to prepare numerous, industrially useful intermediates.