title: The degradation of [14C]molinate in soil under flooded and nonflooded conditions.
abstract: The degradation of [14C]molinate in soil under flooded and nonflooded conditions was investigated. In laboratory studies, 50 percent of the applied molinate was lost in 3 weeks under moist soil conditions, while under flooded conditions, dissipation was reduced to 50 percent loss in 10 weeks. Analysis for molinate and its degradation products in the soil and flood water showed that under flooded conditions very little breakdown of molinate occurred, and volatilization was the primary mode of dissipation. However, under nonflooded conditions, hydroxylation of the azepine ring and further oxidation to the respective ketones occurs. Oxidation to form the sulfoxide, cleavage to yield the imine, and acetylation of the imine are also proposed. Other pathways appear to involve desethylation to produce a free thiocarbamic acid derivative followed by S-methylation as well as carboxylation of the S-ethyl group.
mesh_terms: D001381:Azepines; D002250:Carbon Radioisotopes; D055598:Chemical Phenomena; D002621:Chemistry; D004190:Disasters; D008401:Gas Chromatography-Mass Spectrometry; D007700:Kinetics; D012987:Soil; D013859:Thiocarbamates; D014867:Water
chemical_list: D001381:Azepines; D002250:Carbon Radioisotopes; D012987:Soil; D013859:Thiocarbamates; D014867:Water; C009821:molinate