Dichloroacetyl chloride is the organic compound with the formula CHCl2COCl. It is the acyl chloride of dichloroacetic acid. It is a colourless liquid and is used in acylation reactions.
Preparation Unlike typical acid chlorides, which are often prepared from the associated carboxylic acid, dichloroacetyl chloride is not prepared from dichloroacetic acid. Instead, industrial routes include oxidation of 1,1,2-trichloroethane, hydrolysis of pentachloroethane, and the carboxylation of chloroform: CHCl2CH2Cl + O2 → CHCl2COCl + H2O CHCl2CCl3 + H2O → CHCl2COCl + 2 HCl CHCl3 + CO2 → CHCl2COCl + 1/2 O2
Uses It is a precursor to various herbicides including dichlormid. It is one of the precursors to antibiotics, including chloramphenicol.
Selected reactions Dichloroacetyl chloride undergoes dehydrochlorination upon treatment with base to generate dichloroketene.
Hydrolysis of dichloroacetyl chloride gives dichloroacetic acid.
References