1-Methyl-1H-pyrazole-5-carboxylic acid

1-Methyl-1H-pyrazole-5-carboxylic acid Property

Melting point:

220-225 °C

Boiling point:

306.9±15.0 °C(Predicted)

Density 

1.34±0.1 g/cm3(Predicted)

storage temp. 

Keep in dark place,Sealed in dry,Room Temperature

form 

powder to crystal

pka

3.03±0.25(Predicted)

color 

White to Almost white

λmax

259nm(MeOH)(lit.)

InChIKey

JREJQAWGQCMSIY-UHFFFAOYSA-N

CAS DataBase Reference

16034-46-1(CAS DataBase Reference)

Safety

Hazard Codes 

Xi

Risk Statements 

36/37/38

Safety Statements 

26-37/39

RIDADR 

2811

WGK Germany 

3

Hazard Note 

Harmful

HazardClass 

IRRITANT

HS Code 

29331990

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P271Use only outdoors or in a well-ventilated area.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P302+P352IF ON SKIN: wash with plenty of soap and water.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

1-Methyl-1H-pyrazole-5-carboxylic acid Chemical Properties,Usage,Production

Chemical Properties

White to yellow solid

Uses

1-Methyl-5-pyrazolecarboxylic acid is a biochemical reagent that can be used as a biological material or organic compound for life science related research.

Definition

ChEBI: 1-methyl-pyrazole-5-carboxylic acid is a member of the class of pyrazoles that is N-methylpyrazole substituted by a carboxy group substituents at position 5. It has a role as a metabolite. It is a member of pyrazoles and a monocarboxylic acid. It is functionally related to a N-methylpyrazole.

Synthesis

1-Methyl-1H-pyrazole (2.0 g, 24.4 mmol) was dissolved in tetrahydrofuran (THF, 30 mL) at room temperature. The reaction mixture was cooled to -78 °C under nitrogen protection, followed by slow dropwise addition of n-butyllithium (n-BuLi, 10.72 mL, 26.8 mmol). The reaction temperature of -78 °C was maintained and the reaction mixture was stirred for 2 h. Subsequently, it was gradually warmed up to room temperature and stirring was continued for 1 h. The reaction temperature was maintained at -78 °C. Under the condition of maintaining the reaction temperature, dry carbon dioxide gas was passed into the reaction solution for about 5 minutes. The reaction mixture continued to be stirred at room temperature for 1 hour. Subsequently, water (30 mL) was added to the reaction mixture to quench the reaction and dilute the mixture. The reaction mixture was extracted with dichloromethane. After precipitation of a large amount of solid from the acidic aqueous phase, the separation was carried out by filtration. The resulting filter cake was dried to give a final 1.5 g of white solid product 1-methyl-1H-pyrazole-5-carboxylic acid in 48.8% yield.

References

[1] ACS Medicinal Chemistry Letters, 2015, vol. 6, # 6, p. 650 - 654
[2] Patent: CN105384739, 2016, A. Location in patent: Paragraph 0345; 0346; 0347
[3] Patent: WO2009/71705, 2009, A1. Location in patent: Page/Page column 39
[4] Patent: WO2009/71706, 2009, A1. Location in patent: Page/Page column 48
[5] Patent: US2008/242661, 2008, A1. Location in patent: Page/Page column 25