Fungicides and photochemistry photodegradation of the dicarboximide fungicide iprodione

To examine the potential of the fungicide iprodione ( ) (3-(3,5-dichlorophenyl)-N-(1-methylethyl)2,4-dioxo-1-imidazolidinecarboxamide) to undergo photochemical reactions on plant surfaces model experiments λ > 280 run) were performed in various organic solvents simulating the plant cuticle environment. Photodegradation of iprodione was more efficient in isopropanol than in a saturated (cyclohexane) or an unsaturated hydrocarbon medium (cyclohexene). In isopropanol and cyclohexane mainly photodehalogenation reactions of the fungicide were observed whereby in side reactions substitutions of the chlorines by solvent molecules took place. On the other hand, in cyclohexene solutions, substitutions of the chlorines by solvent molecules were mainly observed.