Abstrait

Examination of the electrochemical behaviour of the imidazolinone herbicides imazapyr, imazethapyr and imazaquin on mercury electrodes

M.RuizMontoya,S.Pintado, J.M.RodriguezMellado

Polarographic (dc and DP) studies have been made on the reduction of the imidazolinone herbicides imazapyr[2-(4- isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl) nicotinic acid], imazethapyr[5-ethyl-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin- 2-yl) nicotinic acid] and imazaquin[2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl) quinoline-3-carboxylic acid] in the acidity range 2.7MH2SO4 to pH 13.At pH<7 the DP polarograms showed two sets of peaks that depended strongly on the pH and can be assigned to the reduction of the two reducible parts of the molecule, i.e., the pyridinic (or quinolinic) and the imidazolinic rings. The results suggest that the set of peaks appearing at more negative potentials could be related to the pyridinic/quinolinic ring reduction, being the assignation of the peaks appearing at less negative potentials more difficult.