| Abstract: | Four 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 at least 10 times higher than those occurring after actual field application. |
