Nitrite or nitrate induced-photolysis of monolinuron (a phenyl urea herbicide) using the 300–450 nm light excitation gives rise to various photo-products. The direct photolysis of monolinuron proceeds via two main pathways yielding, respectively, 3-(4-chlorophenyl)-1-methylurea, which results from demethoxylation of the N-terminus substituted functional group and 3-(4-hydroxyphenyl)-1-methoxy-1- methylurea obtained by photohydrolysis of the C-Cl bond[1].
Degradation pathways of monolinuron by direct and nitrite (or nitrate) induced photolysis. Specific photoproducts: circled numbers (direct); underlined numbers (induced):
