100784-27-8Relevant articles and documents
Halosulfuron methyl intermediate synthesis method
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Paragraph 0029; 0035; 0036, (2017/10/07)
The invention discloses a halosulfuron methyl intermediate synthesis method. According to the halosulfuron methyl intermediate synthesis method, 3-chloro-1-methylpyrazole-5-hydroxy-4-methyl formate is adopted as a starting raw material; the 3-chloro-1-methylpyrazole-5-hydroxy-4-methyl formate and dimethylthiocarbamoyl chloride are subjected to a condensation reaction to obtain 3-chloro-1-methylpyrazole-5-dimethylaminothioformyloxy-4-methyl formate; a dislocation rearrangement reaction is performed to obtain 3-chloro-1-methylpyrazole-5-dimethylaminoformylsulfo-methyl formate; the 3-chloro-1-methylpyrazole-5-dimethylaminoformylsulfo-methyl formate and chlorine gas are subjected to a chlorosulfonation reaction to obtain 3-chloro-1-methylpyrazole-5-sulfonyl chloride-4-methyl formate; and the 3-chloro-1-methylpyrazole-5-sulfonyl chloride-4-methyl formate and ammonia water are subjected to an ammoniation reaction to obtain the halosulfuron methyl intermediate 3-chloro-1-methylpyrazole-5-sulfonamido-4-methyl formate. According to the present invention, with the method, the environmental pollution is low, especially the product purity is high, and the total yield is high, such that the method is suitable for industrial production.
Transformation kinetics and mechanism of the sulfonylurea herbicides pyrazosulfuron ethyl and halosulfuron methyl in aqueous solutions
Zheng, Wei,Yates, Scott R.,Papiernik, Sharon K.
experimental part, p. 7367 - 7372 (2010/05/18)
Pyrazosulfuron ethyl (PE) and halosulfuron methyl (HM) are two new highly active sulfonylurea herbicides that have been widely used for weed control in a variety of vegetables and other crops. These two herbicides have similar molecular structures, differing only in the substitutions on the pyrazole ring. Chemical hydrolysis is a primary process affecting the environmental fate of sulfonylurea pesticides. The hydrolytic transformation kinetics of PE and HM were investigated as a function of pH and temperature. For both herbicides, the hydrolysis rate was pH-dependent and increased with increasing temperature. The hydrolysis of both sulfonylureas was much faster in acidic or basic media than under neutral conditions. Identification of hydrolytic products by liquid chromatography-mass spectrometry (LC-MS) suggested that both PE and HM were subject to cleavage and contraction of the sulfonylurea bridge. The hydrolysis rate of HM was significantly higher than that of PE in alkaline solutions, despite their structural similarity. A chlorine substitution on HM's pyrazole ring makes HM more susceptible to bridge contraction than PE under basic conditions. The hydrolysis of HM and PE was relatively unaffected by the presence of cyclic oligosaccharides (cyclodextrins), indicating that natural OH-containing organic compounds occurring in aquatic environments may have little impact on the transformation of these sulfonylurea herbicides.
Pyrazolesulfonylurea useful for controlling the growth of undesired vegetation
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, (2008/06/13)
There are disclosed a compound formula (I): STR1 wherein R1 represents a chlorine atom or a bromine atom; R2 represents methyl or ethyl; and X represents methyl or methoxy; a herbicidal composition containing the same as an active ingredient; and a method of use of the compound represented by formula (I) for controlling the growth of weeds without harm to crop plants in the same location.