1-ethyl-1H-pyrazole-4-carboxamide synthesis

Yield:-

Reaction Conditions:

Stage #1:1H-pyrazole-4-carboxylic acid amide with potassium carbonate in N,N-dimethyl-formamide for 0.166667 h;
Stage #2:ethyl bromide in N,N-dimethyl-formamide at 20; for 12 h;

Steps:

62
INTERMEDIATE 621 -Ethyl- 1 H-pyrazole-4-carboxamide To a solution of intermediate 61 (1.5 g, 13.5 mmol) in DMF (4 mL) was added powdered K₂CO₃ (5.6 g, 40.5 mmol). After 10 min, bromoethane (1.2 mL, 16.2 mmol) was added and the mixture was stirred at rt for 12 h. The reaction mixture was diluted with EtOAc, washed with water, dried over MgSO₄ and concentrated to afford the title compound as a white solid (1.0 g), which was used in the next step without purification. LC/MS: m/e 140.1 (M+H)⁺.

References:

MERCK & CO., INC.;CHOBANIAN, Harry;LIN, Linus, S.;LIU, Ping;CHIODA, Marc, D.;DEVITA, Robert, J.;NARGUND, Ravi, P.;GUO, Yan WO2010/17079, 2010, A1 Location in patent:Page/Page column 77