Ethyl 3-amino-4-pyrazolecarboxylate Chemical Properties

Melting point:

105-107 °C(lit.)

Boiling point:

278.95°C (rough estimate)

Density 

1.3092 (rough estimate)

refractive index 

1.6500 (estimate)

storage temp. 

2-8°C

solubility 

Chloroform (Sparingly), Methanol (Slightly)

form 

Crystalline Powder

pka

12.98±0.50(Predicted)

color 

White to yellow

BRN 

4964

Stability:

Light sensitive

InChI

InChI=1S/C6H9N3O2/c1-2-11-6(10)4-3-8-9-5(4)7/h3H,2H2,1H3,(H3,7,8,9)

InChIKey

YPXGHKWOJXQLQU-UHFFFAOYSA-N

SMILES

N1C=C(C(OCC)=O)C(N)=N1

CAS DataBase Reference

6994-25-8(CAS DataBase Reference)

NIST Chemistry Reference

3-Amino-4-carbethoxypyrazole(6994-25-8)

Safety Information

Hazard Codes 

Xi,Xn,N

Risk Statements 

36/37/38-20/21/22-50/53-43

Safety Statements 

26-36-24/25-61-60-36/37

RIDADR 

UN 3077 9 / PGIII

WGK Germany 

3

HazardClass 

IRRITANT

HS Code 

29331990

MSDS

• Language:English Provider:Ethyl 3-amino-4-pyrazolecarboxylate
• Language:English Provider:ACROS
• Language:English Provider:SigmaAldrich
• Language:English Provider:ALFA

Ethyl 3-amino-4-pyrazolecarboxylate Usage And Synthesis

Chemical Properties

Off-White Powder

Uses

Ethyl 3-Amino-4-pyrazolecarboxylate (Allopurinol EP Impurity D) is an impurity of Allopurinol (A547300), a pyrazole derivative that has been shown to induce neoplasm immunogenicity.

General Description

Pharmaceutical secondary standards for application in quality control provide pharma laboratories and manufacturers with a convenient and cost-effective alternative to the preparation of in-house working standards

Synthesis

General procedure for the synthesis of ethyl 5-amino-1H-pyrazole-4-carboxylate from ethyl ethoxymethylcyanoacetate: ethyl ethoxymethylcyanoacetate (68 g, 0.4 mol) was added to a reaction vessel containing 200 mL of anhydrous ethanol; 100 mL of hydrazine hydrate was added slowly and dropwise to the reaction vessel. The reaction mixture was placed in an electric heating jacket and gradually heated up to 80 °C within 30 min to obtain mixture A. The mixture A was heated to reflux and kept in reflux reaction for 4 h. The reaction was carried out under reduced pressure. Upon completion of the reaction, ethanol was removed by distillation under reduced pressure and the remaining solid was concentrated by evaporation. The concentrated solid was cooled to room temperature and left to precipitate a light yellow solid, which was filtered, washed and dried to give the intermediate ethyl 5-amino-1H-pyrazole-4-carboxylate. Cold anhydrous ethanol was used for the washing process. The mass of the final product ethyl 5-amino-1H-pyrazole-4-carboxylate was 41.68 g and the yield was 66.78%.

References

[1] Patent: CN105949202, 2016, A. Location in patent: Paragraph 0048-0053
[2] Patent: CN106008517, 2016, A. Location in patent: Paragraph 0048; 0049; 0050; 0051; 0052; 0053
[3] Patent: CN106008519, 2016, A. Location in patent: Paragraph 0048; 0049; 0050; 0051; 0052; 0053
[4] Patent: CN105949199, 2016, A. Location in patent: Paragraph 0047-0052
[5] Patent: CN105949200, 2016, A. Location in patent: Page/Page column 6; 7; 23

Ethyl 3-amino-4-pyrazolecarboxylate(6994-25-8)Related Product Information

• ethyl 5-(forMylaMino)-1H-pyrazole-4-carboxylate
• 5-(forMylaMino)-1H-pyrazole-4-carboxaMide
• 5-AMINO-1H-PYRAZOLE-4-CARBOXYLIC ACID ETHYL ESTER
• 3-Aminopyrazole
• 4-Pyrazolecarboxylic acid
• 3-Aminopyrazole-4-carboxylic acid
• Ethyl pyrazole-4-carboxylate
• 4-AMINO-2 H-PYRAZOLE-3-CARBOXYLIC ACID ETHYL ESTER
• Oxipurinol
• Allopurinol Impurity 1
• ALLOPURINOL IMPURITY C
• Allopurinol Related CoMpound F
• Allopurinol-d2
• Allopurinol
• Oxypurinol -13C, 15N2
• ALLOPURINOL RIBOSIDE
• 3-Amino-1H-pyrazole-4-carboxamide
• 5-[(1-Methylpiperidin-2-ylidene)amino]-1H-pyrazole-4-carboxylic acid ethyl ester