Sulfuric Acid → Pyrazosulfuron-ethyl

HRID 374572Notes

Reaction equation

HRID 374572 reaction equation
[CH2:1]([O:3][C:4]([C:6]1[CH:7]=[N:8][N:9]([CH3:15])[C:10]=1[S:11](Cl)(=[O:13])=[O:12])=[O:5])[CH3:2].[O-:16][C:17]#[N:18].[Na+].[CH3:20][O:21][C:22]1[CH:27]=[C:26]([O:28][CH3:29])[N:25]=[C:24]([NH2:30])[N:23]=1.S(=O)(=O)(O)O>C(#N)C.ClCCl.N1C=CC=CC=1>[CH3:20][O:21][C:22]1[CH:27]=[C:26]([O:28][CH3:29])[N:25]=[C:24]([NH:30][C:17]([NH:18][S:11]([C:10]2[N:9]([CH3:15])[N:8]=[CH:7][C:6]=2[C:4]([O:3][CH2:1][CH3:2])=[O:5])(=[O:13])=[O:12])=[O:16])[N:23]=1

Participants

8

Reactant 4

HCID 1118Sulfuric AcidHCID 1189462-Amino-4,6-dimethoxypyrimidineHCID 517096Sodium CyanateHCID 109779631-methyl-4-ethoxycarbonylpyrazole-5-sulfonylchloride

Product 1

HCID 91750Pyrazosulfuron-ethylYield 99%

Reagents, catalysts & solvents 3

HCID 1049PyridineSolventHCID 6342AcetonitrileSolventHCID 6344DichloromethaneSolvent

Conditions

Temperature
40 °C

Procedure

2.603 g of 4-ethoxycarbonyl-1-methylpyrazole-5-sulfonylchloride was dissolved in 20.0 ml of acetonitrile. To the resulting solution were added 0.715 g of sodium cyanate and 1,552 g (10.0 mM) of 4,6-dimethoxy-2-aminopyrimidine with stirring. The reaction mixture was maintained at 40° C. for about 10 minutes and then 0.396 g of pyridine was added dropwise thereto over 5 minutes via a syringe. While maintaining the temperature of 40° to 45° C., the reaction mixture was continuously and vigorously stirred for 3 hours to complete the reaction. After the reaction was completed, the reaction mixture was adjusted to pH 4 by adding 5% aqueous sulfuric acid solution and dichloromethane to extract the reaction product. The extracted organic layer was dried over anhydrous magnesium sulfate and then filtered. The organic solvent was removed from the filtrate to obtain 4.103 g (Yield 99%) of the title compound in the solid state.

Workup

  1. temperatureWhile maintaining the temperature of 40° to 45° C.
  2. stirringvigorously stirred for 3 hours
  3. customthe reaction
  4. extractionto extract the reaction product
  5. dry with materialThe extracted organic layer was dried over anhydrous magnesium sulfate
  6. filtrationfiltered
  7. customThe organic solvent was removed from the filtrate

Sources & evidence

ORD record
ord-2bc992b923ee42249c60809a5e898a70
Source dataset
uspto-grants-1996_01
Patent number
US05480993

Reaction notes

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