4-Methoxybenzoyl Chloride

4-Methoxybenzoyl chloride (anisoyl chloride) is a colorless liquid or low-melting solid — an important aromatic acyl chloride intermediate with an irritating odor, decomposing on contact with water or alcohol. Melting point 16-19 °C, boiling point 263 °C; purity above 99.0% with strict control of anhydride and residual acid.

The acyl chloride group undergoes alcoholysis (giving anisate esters), aminolysis (amides), hydrolysis and Friedel-Crafts acylation; the methoxy group is an ortho/para director enabling multi-substituted anisic acid derivatives.