AbstractFour coupling products formed by one‐electron oxidation of 4‐chloro‐o‐toluidine were isolated from soil samples after 90 days of incubation with [14C]chlordimeform (200 mg/kg). The metabolic compounds were identified as 4,4′‐dichloro‐2,2′‐dimethyl‐azobenzene, 4‐chloro‐6‐nitro‐o‐toluidine,N‐(4‐chloro‐o‐tolyl)‐2‐methyl‐p‐benzoquin‐one monoimine and 2‐(4‐chloro‐o‐toluidino)‐N‐(4‐chloro‐o‐tolyl)‐6‐methyl‐p‐benzo‐quinone monoimine, respectively. Mechanisms of formation and possible significance of these substances as indicators for metabolic pathways to mineralisation of aniline derivatives are discussed. The chlordimeform soil concentrations (70–100 mg/kg) necessary for the formation of the azobenzene and the benzoquinone monoimines are