1-BENZYL-1H-PYRAZOLE-4-CARBALDEHYDE

1-BENZYL-1H-PYRAZOLE-4-CARBALDEHYDE Property

Melting point:

44.0 to 48.0 °C

Boiling point:

144°C/0.5mmHg(lit.)

Density 

1.12±0.1 g/cm3(Predicted)

storage temp. 

under inert gas (nitrogen or Argon) at 2-8°C

solubility 

soluble in Methanol

form 

powder to lump to clear liquid

pka

-0.07±0.10(Predicted)

color 

White or Colorless to Light yellow

Safety

HS Code 

2933199090

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.

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

1-BENZYL-1H-PYRAZOLE-4-CARBALDEHYDE Chemical Properties,Usage,Production

Synthesis

At room temperature, (1-benzyl-1H-pyrazol-4-yl)methanol (190 mg, 1.0 mmol) was dissolved in dichloromethane (8 mL) and Dess-Martin periodinane (670 mg, 1.58 mmol) was added. The reaction mixture was stirred at room temperature for 1.5 h. After stirring, the reaction was quenched with a mixture of saturated sodium thiosulfate solution and 10% sodium bicarbonate solution (1:1, v/v) and stirring was continued for 30 min. Subsequently, the reaction mixture was extracted with dichloromethane (3 x 30 mL). The organic phases were combined, washed sequentially with saturated aqueous sodium bicarbonate and brine, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by fast column chromatography (Isco CombiFlash, eluent: 0-40% ethyl acetate/heptane) to afford 1-benzyl-1H-pyrazole-4-carbaldehyde (86 mg, 46% yield). The product was confirmed by 1H NMR (400 MHz, CDCl3): δ 5.35 (s, 2H), 7.27-7.30 (m, 2H), 7.36-7.43 (m, 3H), 7.88 (s, 1H), 8.01 (s, 1H), 9.85 (s, 1H); LCMS-MS (ESI+) m/z: 186.90 ([M+H ]+).

References

[1] Patent: US2008/4327, 2008, A1. Location in patent: Page/Page column 76
[2] Patent: WO2005/42534, 2005, A2. Location in patent: Page/Page column 42-43