Synthetic Route of 37718-11-9, These common heterocyclic compound, 37718-11-9, name is 1H-Pyrazole-4-carboxylic acid, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
To a suspension of lH-pyrazole-4-carboxylic acid (50 g, 446 mmol) in 500 ml DMF was added p-toluenesulfonic acid(8.48 g, 44 mmol) and DHP (132 mL, 1561 mmol).The reaction medium turned yellow and then changed at room temperature for 20 hoursblack. The reaction mixture was poured into saturated aqueous NaHCO3 and extracted with EtOAc. The aqueous phase was added by the addition of 6M hydrochloric acid solutionTo pH = 3. The resulting precipitate was filtered off and washed with water and then dried in vacuo at 50 C to give 61.2 g of a white powder(Yield: 70%).
The synthetic route of 37718-11-9 has been constantly updated, and we look forward to future research findings.