IDENTIFICATION OF DIFFERENT PRODUCTS OBTAINED BY ELECTROCHEMICAL AND PHOTOCHEMICAL REDUCTION OF THE HERBICIDE MOETAMITRON

The electrochemical reduction of the herbicide Metamitron 4,5-dihydro- 3-methyl-6-phenyl-1,2,4-triazin-5-one) has been carried out at differe nt pHs using a mercury pool cathode. The final product of these reduct ions depends both on the electrolysis potential and on the pH. All pro cesses are irreversible and the reductions of the C = N and the N - NH 2 (pH > 3) or N - NH3+ bond (pH < 3) are inferred. An aqueous solution of Metamitron is also degraded by sunlight leading to 4,5-dihydro-3-m ethyl-6-phenyl-1,2,4-triazin-5-one (deaminometamitron). This reaction can be monitored polarographically.