Dichloroacetyl chloride

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.

Hydrolysis gives dichloroacetic acid. It is one of the precursors to antibiotics, including chloramphenicol.