تفاعل #58907

معادلة التفاعل

5-(4-fluorophenyl)-1-methyl-1H-pyrazole-4-carbaldehyde

sodium hydride

ethyl diethylphosphonoacetate

N,N-dimethylformamide

→

(2E)-3-[5-(4-fluorophenyl)-1-methyl-1H-pyrazol-4-yl]acrylic acid

المردود 84.0%

المذيبات

water

ظروف التفاعل

المعالجة

1. 1
   ترشيحthe precipitated solids were collected by filtration
2. 2
   أخرىAfter drying with airflow
3. 3
   workup.DISSOLUTIONthe solids were dissolved in a mixed solvent of tetrahydrofuran (10 ml) and ethanol (10 ml)
4. 4
   workup.ADDITIONA 1N aqueous sodium hydroxide solution (5 ml) was added
5. 5
   workup.STIRRINGthe mixture was stirred at room temperature for 2 hrs
6. 6
   workup.ADDITIONThe reaction mixture was poured into a 10% aqueous citric acid solution
7. 7
   ترشيحthe precipitated solids were collected by filtration
8. 8
   غسيلwashed with water
9. 9
   أخرىdried with airflow

الإجراء التجريبي

A mixture of 5-(4-fluorophenyl)-1-methyl-1H-pyrazole-4-carbaldehyde (350 mg), sodium hydride (60% in oil, 120 mg), ethyl diethylphosphonoacetate (673 mg) and N,N-dimethylformamide (10 ml) was stirred at room temperature for 1 hr. The reaction mixture was poured into water, and the precipitated solids were collected by filtration. After drying with airflow, the solids were dissolved in a mixed solvent of tetrahydrofuran (10 ml) and ethanol (10 ml). A 1N aqueous sodium hydroxide solution (5 ml) was added and the mixture was stirred at room temperature for 2 hrs. The reaction mixture was poured into a 10% aqueous citric acid solution and the precipitated solids were collected by filtration, washed with water and dried with airflow to give (2E)-3-[5-(4-fluorophenyl)-1-methyl-1H-pyrazol-4-yl]acrylic acid (354 mg, 84%) as crystals. Recrystallization thereof from methanol-isopropyl ether gave colorless prism crystals. melting point: 212-213° C.

المصدر