Trichlorobenzoic acids (TBAs) are organochlorine compounds, in particular benzoic acids, with the formula . Six constitutional isomers exist, differing in the relative position of the three chlorine substituents around the ring.
The 2,4,6- isomer is easily produced by deprotonation of 1,3,5-trichlorobenzene followed by reaction with carbon dioxide.[1] Its conversion to 2,4,6-trichlorobenzoyl chloride makes it a key intermediate in the Yamaguchi esterification protocol.