3-(4-FLUOROPHENYL)-1H-PYRAZOLE-4-CARBALDEHYDE

3-(4-FLUOROPHENYL)-1H-PYRAZOLE-4-CARBALDEHYDE Property

Melting point:

160 °C

Boiling point:

416.0±35.0 °C(Predicted)

Density 

1.337±0.06 g/cm3(Predicted)

storage temp. 

2-8°C, stored under nitrogen

form 

powder to crystal

pka

10.69±0.50(Predicted)

color 

White to Orange to Green

Sensitive 

Air Sensitive

CAS DataBase Reference

306936-57-2(CAS DataBase Reference)

Safety

Hazard Codes 

Xi

Risk Statements 

36/37/38

Safety Statements 

26-36/37/39

WGK Germany 

3

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.

3-(4-FLUOROPHENYL)-1H-PYRAZOLE-4-CARBALDEHYDE Chemical Properties,Usage,Production

Chemical Properties

White to yellow-orange solid

Synthesis

General procedure for the synthesis of 3-(4-fluoropropyl)-1H-pyrazole-4-carbaldehyde from 2-(1-(4-fluorophenyl)ethylidene)hydrazine-1-carboxamide and N,N-dimethylformamide: Phosphorochloride (2.1 mL, 23 mmol) was slowly added dropwise to N,N-dimethylformamide (4.4 mL, 57 mmol) at 0 °C. The reaction mixture was stirred at 0 °C for 30 min, then brought to room temperature and continued stirring for 30 min. Subsequently, the reaction mixture was cooled in an ice/water bath and 2-(1-(4-fluorophenyl)ethylidene)hydrazine-1-carboxamide (1.96 g, 10 mmol) was slowly added, controlling the temperature not to exceed 50 °C. After the addition was completed, the reaction system was heated to 80 °C and stirred at this temperature for 2 hours. After completion of the reaction, the mixture was poured into ice (15 g) and the pH was adjusted to 10 with 5N NaOH solution and stirred for 2 hours. Subsequently, the reaction solution was acidified with concentrated hydrochloric acid and stirring was continued for 4 hours. The precipitated solid was collected by filtration, washed with a small amount of water and dried under high vacuum to give the target product 3-(4-fluoropropyl)-1H-pyrazole-4-carbaldehyde (1.5 g, 79% yield).

References

[1] Bioorganic and Medicinal Chemistry Letters, 2008, vol. 18, # 18, p. 4932 - 4935
[2] Russian Journal of General Chemistry, 2005, vol. 75, # 5, p. 782 - 789
[3] Patent: WO2013/22766, 2013, A1. Location in patent: Page/Page column 87
[4] European Journal of Medicinal Chemistry, 2017, vol. 133, p. 36 - 49
[5] Journal of Fluorine Chemistry, 2016, vol. 183, p. 59 - 68