ChemicalBook CAS DataBase List 1H-Pyrazole-3-carboxylic acid, 4-phenyl-, ethyl ester

1H-Pyrazole-3-carboxylic acid, 4-phenyl-, ethyl ester synthesis

4synthesis methods

Product Name:1H-Pyrazole-3-carboxylic acid, 4-phenyl-, ethyl ester
CAS Number:6963-62-8
Molecular formula:C12H12N2O2
Molecular Weight:216.24

5292-53-5

1H-Pyrazole-3-carboxylic acid, 4-phenyl-, ethyl ester

6963-62-8

General procedure for the synthesis of ethyl 4-phenyl-1H-pyrazole-3-carboxylate from diethyl benzylidene malonate: in a 10 mL microwave glass vial, EtOH (1 mL) and pyrazolidine 6 (0.1 mmol) were added, followed by Cs2CO3 (16.5 mg, 0.05 mmol, 0.5 equiv). The reaction mixture was placed in a microwave reactor and radiated at 80°C for 10-15 min and the reaction progress was monitored by TLC. Upon completion of the reaction, EtOH was removed under vacuum. the residue was treated with 10 mL of water and the aqueous phase was extracted with EtOAc (2 × 10 mL). The organic phases were combined, dried with anhydrous Na2SO4, filtered and the filtrate was concentrated under vacuum. The residue was recrystallized by EtOAc/hexane (1:1) mixed solvent to give pure ethyl 4-phenyl-1H-pyrazole-3-carboxylate (compound 5) in quantitative yield.

5292-53-5 Synthesis

5292-53-5
101 suppliers
$14.00/5g

6963-62-8
44 suppliers
$80.00/100mg

Yield:6963-62-8 96%

Reaction Conditions:

with ethanol;caesium carbonate at 80; for 0.25 h;Microwave irradiation;

Steps:

4.5 General procedure for the synthesis of pyrazole carboxylate 5 from 6 pyrazoline 6 under MW irradiation (see Scheme 5)

General procedure: In a 10mL microwave glass vial containing EtOH (1mL), was added pyrazoline 6 (0.1mmol) followed by Cs₂CO₃ (16.5mg, 0.05mmol, 0.5 equiv) and the resulting mixture was subjected to microwave irradiation for 10-15minat 80°C until the completion of reaction (monitored by TLC). After removal of EtOH in vacuo, the residue was treated with water (10mL) and the aqueous layer was extracted with EtOAc (2×10mL). The combined organic layer was dried over anhydrous Na₂SO₄, filtered and the filtrate was then concentrated in vacuo. The residue was recrystallized from EtOAc/hexane (1:1) to obtain pure 5 in quantitative yields.

References:

Nair, Deepa;Pavashe, Prashant;Namboothiri, Irishi N.N. [Tetrahedron,2018,vol. 74,# 22,p. 2716 - 2724]