1H-Pyrazole-4-sulfonylchloride,1-methyl-(9CI) Chemical Properties

Boiling point:

295.7±13.0 °C(Predicted)

Density 

1.60±0.1 g/cm3(Predicted)

storage temp. 

Keep in dark place,Sealed in dry,Room Temperature

form 

crystalline solid

pka

-3.33±0.10(Predicted)

color 

White

Sensitive 

Moisture Sensitive

InChI

InChI=1S/C4H5ClN2O2S/c1-7-3-4(2-6-7)10(5,8)9/h2-3H,1H3

InChIKey

RDAVKKQKMLINOH-UHFFFAOYSA-N

SMILES

N1(C)C=C(S(Cl)(=O)=O)C=N1

Safety Information

Hazard Codes 

Xi

Risk Statements 

43

Safety Statements 

36/37

RIDADR 

UN3265

WGK Germany 

3

HazardClass 

IRRITANT

HazardClass 

8

HS Code 

2933199090

1H-Pyrazole-4-sulfonylchloride,1-methyl-(9CI) Usage And Synthesis

Uses

1-Methyl-1H-pyrazole-4-sulfonyl Chloride is used as a reagent in the preparation of benzoindazoles as glucocorticoid receptor modulators.

Synthesis

1-Methyl-1H-pyrazole (100 g, 1.18 mol) was slowly added dropwise to chlorosulfonic acid (325 mL, 4.84 mol) at 0 °C and under nitrogen protection, keeping stirring. The reaction mixture was then heated to reflux at 110 °C for 3 hours. Upon completion of the reaction, the mixture was cooled to room temperature and quenched by careful pouring into crushed ice with continuous stirring. The precipitated white solid product was collected by vacuum filtration and washed well with cold water. Finally, the product was dried under vacuum to afford 1-methyl-1H-pyrazole-4-sulfonyl chloride (72.2 g, 33% yield), which can be used in subsequent reactions without further purification.

References

[1] Patent: WO2009/29439, 2009, A1. Location in patent: Page/Page column 24
[2] Patent: US6103708, 2000, A
[3] Patent: WO2005/97162, 2005, A2. Location in patent: Page/Page column 432

1H-Pyrazole-4-sulfonylchloride,1-methyl-(9CI)(288148-34-5)Related Product Information

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