preparation method of sulfometuron methyl

1, 2 - amino answering methyl pyrimidine preparation: two first by the dicyandiamide and ammonium nitrate (or carbonate) function system nitric acid guanidinium(WeiKu) (or carbonate guanidinium), then will 12.2 g nitric acid guanidinium, 10g acetyl acetone, 100mL canister water and 8g potash response at room temperature. The filter, drying post-processing 7.4 g 2 - amino answering two methyl pyrimidines, yield 60%.
2 and adjacent formic acid methyl benzene sulfonylureas acyl isocyanate preparation: will 30g saccharin 250mL after mixing with methanol, at 0 ℃ below ventilation with hydrogen gas, steam out excessive reaction Picasso methanol. Residue add ethyl acetate, filtering, steamed out of ethyl acetate, heavy crystallization, methyl formate benzene to adjacent sulfonylureas amide.
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3, its sulfonylureas RON's synthesis: 2 - amino answering two methyl thymine (methyl formate 4g) and o-chloroaniline benzene sulfonylureas acyl isocyanate (7.8 g) in acetonitrile solvent, 60mL) (fall at room temperature, reaction 16h stir white crystals, yield filter 91%.