100784-20-1Relevant articles and documents
Evaluation of Synthesis of Methyl 3-Chloro-5-(4,6-dimethoxypyrimidin-2-ylcarbamoylsulfamoyl)-1-methylpyrazole-4-carboxylate Using Green Metrics
Gilbile, Rohidas,Bhavani, Ram,Vyas, Ritu
, p. 1477 - 1481 (2017)
A modified synthesis of methyl 3-chloro-5-(4,6-dimethoxypyrimidin-2-ylcarbamoylsulfamoyl)-1-methylpyrazole-4-carboxylate (halosulphuron) is described. The merits of the synthesis are (i) one pot chlorination of methyl 1-methyl-1 H-pyrazole-4-carboxylate (1) in presence of sulphuryl chloride resulting in methyl 3,5-dichloro-1-methyl-1 H-pyrazole-4-carboxylate (2) (ii) conversion of 3-chloro-5-mercapto-1-methyl-1 H-pyrazole-4-carboxylate (3) to 3-chloro-1-methyl-5-sulfamoyl pyrazole-4-carboxylate (4) under mild reaction conditions utilizing tetrabutyl ammonium chloride, N-chlorosuccinimide and ammonium carbonate (iii) condensation of sulphonamide (4) with carbamate (6) by microwave irradiation. Efforts were made to calculate, atom economy, reaction mass efficiency and E-factor for all the reaction steps involved in the synthesis of halosulfuron. The E-factor values in step 2 and step 4 reaction is lower, indicating that these reactions are greener (generation of less waste) when compared to the remaining steps in the synthesis.
Form of halosulfuron-methyl, a process for its preparation and use of the same
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, (2017/05/02)
The present invention describes the crystalline form of halosulfuron-methyl of formula (I), the crystal preparation process, the analyses of the crystal through various analytical methods and using the crystal to prepare stable agrochemical formulation. The invention also describes the use of various solvents towards the crystalline form preparation conditions.
Synthesis of Halosulfuron-methyl via Selective Chlorination at 3- and/or 5-Position of Pyrazole-4-carboxylates
Morimoto, Katsushi,Sato, Toshiaki,Yamamoto, Susumu,Takeuchi, Hiroshi
, p. 537 - 540 (2007/10/03)
Reactions of methyl pyrazole-4-carboxylates 4b-d with N-chlorosuccinimide under heating conditions without a solvent gave methyl 3,5-dichloro-1-methylpyrazole-4-carboxylate 4a in good yields. The reaction of 4a with sodium hydrosulfide led to a nucleophilic substitution on the 5-position regioselectively to afford methyl 3-chloro-1-methyl-5-mercaptopyrazole-4-carboxylate 6a, which was followed by oxidative chlorination and amination to obtain 3-chloro-1-methyl-5-sulfamoylpyrazole-4-carboxylate 2a. Finally, the reaction of 2a with phenyl 4,6-dimethoxypyrimidin-2-yl carbamate 7 provided methyl 3-chloro-5-(4,6-dimethoxypyrimidin-2-ylcarbamoylsulfamoyl)-1-methylpyrazole-4- carboxylate (halosulfuron-methyl) 1a promising herbicide in corn.