4-Bromo-3,5-dimethylpyrazole Chemical Properties

Melting point:

123-125 °C(lit.)

Boiling point:

269.1±35.0 °C(Predicted)

Density 

1.595

refractive index 

1.5500 (estimate)

storage temp. 

Keep in dark place,Sealed in dry,Room Temperature

solubility 

soluble in Methanol

form 

powder to crystal

pka

13.83±0.50(Predicted)

color 

White to Light yellow

BRN 

108534

InChI

InChI=1S/C5H7BrN2/c1-3-5(6)4(2)8-7-3/h1-2H3,(H,7,8)

InChIKey

RISOHYOEPYWKOB-UHFFFAOYSA-N

SMILES

N1C(C)=C(Br)C(C)=N1

CAS DataBase Reference

3398-16-1(CAS DataBase Reference)

Safety Information

Hazard Codes 

Xi

Risk Statements 

36/37/38

Safety Statements 

26-37/39

WGK Germany 

3

RTECS 

UQ6210000

HazardClass 

IRRITANT

HS Code 

29331990

Toxicity

LD50 intraperitoneal in mouse: 580mg/kg

MSDS

• Language:English Provider:SigmaAldrich
• Language:English Provider:ACROS
• Language:English Provider:ALFA

4-Bromo-3,5-dimethylpyrazole Usage And Synthesis

Chemical Properties

white crystalline powder

Uses

4-Bromo-3,5-dimethylpyrazole is a biochemical reagent that can be used as a biological material or organic compound for life science related research.

Synthesis

The general procedure for the synthesis of 3,5-dimethyl-4-bromopyrazole from 3,5-dimethylpyrazole is as follows: 1. In a 16 mL vial, 1-benzyl-3,5-dimethyl-1H-pyrazole (196 mg, 1.05 mmol), a magnetic stir bar, 0.7 mL of water, and 0.3 mL of ethyl acetate were added. 2. NaCl (123 mg, 2 mmol) was added and the vial was placed in a room temperature water bath to control the exothermic nature of the reaction. 3. Oxone (322 mg, 0.52 mmol or 1.05 mmol KHSO5) was added and the vial was capped. 4. React under continuous vigorous stirring until thin layer chromatography (TLC) analysis (1 hr) showed complete consumption of the raw material. 5. Reduce the remaining oxidizing agent using solid sodium bisulfite until the starch iodide paper tests negative. 6. Water (5 mL) was added and the reaction mixture was extracted with a 1:1 hexane/ether solvent mixture (3 x 5 mL). 7. The organic phases were combined, dried over anhydrous magnesium sulfate (MgSO4) and concentrated to give the crude product. 8. The crude product was purified by fast chromatography (14 x 1 cm, eluent 9:1 hexane/ethyl acetate) to afford pure 1-benzyl-4-chloro-3,5-dimethyl-1H-pyrazole as a light yellow oil (215 mg, 93% yield).

References

[1] Tetrahedron Letters, 2005, vol. 46, # 40, p. 6833 - 6837
[2] Chemical & Pharmaceutical Bulletin, 1988, vol. 36, # 10, p. 3838 - 3848
[3] Tetrahedron Letters, 2017, vol. 58, # 43, p. 4111 - 4114
[4] Canadian Journal of Chemistry, 1992, vol. 70, # 4, p. 1121 - 1128
[5] Journal of the Chemical Society, 1923, vol. 123, p. 1315

4-Bromo-3,5-dimethylpyrazole(3398-16-1)Related Product Information

• 3,5-Dimethylpyrazole
• Pyraclostrobin
• Zolpidem tartrate
• 5-Methyl-2-phenyl-1,2-dihydropyrazol-3-one
• Dimethyl fumarate
• Pyrazole
• 4-Bromo-1-methylpyrazole
• 4-Bromopyrazole
• Dimethyl sulfate
• ETHANE
• Dacthal
• Dimethyl ether
• Dimethyl carbonate
• Mestinon
• N,N-Dimethylformamide
• Dimethyl sulfoxide
• Zolpidem
• Bromine