Study On The Synthesis Of The High Activity Nicosulfuron Of Sulfonylurea Hebicide

This thesis is about the study of the preparation and production process of sulfonylurea herbicidal nicosulfuron.In this thesis, the synthesis of a sulfonylurea herbicidal, nicosulfuron, was performed and the optimal condition were investigated including 2-ch loro-N,N-dimethylnicotinamide, 2-mercapto-N,N-dimethylnicotinamide,N, N-dimethyl-2-sulfamoylnicotinamide, ethyl 3-(dimethylcarbamoyl)pyridin-2-ylsulfonylcarbamate. The influence of reaction conditions on the result of each intermediate was studied and the technical parameter was optimized. The structures of the products were confirmed by ~1HNMRand MS spectra. Nicosulfuron was synthesized with the carbonic acid ester route avoidi ng the severe toxic phosgene in the thesis, which is much suitable to the de mand of environmentally and benign chemistry.