반응 #58911

반응 방정식

hydrochloric acid

4-(4-fluorophenyl)-4H-1,2,4-triazole-3-carbaldehyde

ethyl diethylphosphonoacetate

sodium hydride

→

(2E)-3-[4-(4-fluorophenyl)-4H-1,2,4-triazol-3-yl]acrylic acid

수율 77.1%

용매

tetrahydrofuran

반응 조건

후처리

1. 1
   추출the mixture was extracted with ethyl acetate
2. 2
   세척The ethyl acetate layer was washed with saturated brine
3. 3
   건조dried over anhydrous magnesium sulfate
4. 4
   농축concentrated
5. 5
   workup.DISSOLUTIONThe residue was dissolved in a 6N aqueous hydrochloric acid solution (100 ml)
6. 6
   workup.STIRRINGstirred for 2 hrs
7. 7
   온도with heating
8. 8
   온도under reflux
9. 9
   workup.ADDITIONDisodium hydrogen phosphate was added
10. 10
    여과The precipitated solids were collected by filtration
11. 11
    세척washed with water
12. 12
    기타dried

실험 절차

A mixture of 4-(4-fluorophenyl)-4H-1,2,4-triazole-3-carbaldehyde (3.83 g), ethyl diethylphosphonoacetate (5.60 g), sodium hydride (60% in oil, 0.88 g) and tetrahydrofuran (130 ml) was stirred at 0° C. for 1 hr. The reaction mixture was poured into an aqueous dilute hydrochloric acid solution and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated. The residue was dissolved in a 6N aqueous hydrochloric acid solution (100 ml) and stirred for 2 hrs. with heating under reflux. Disodium hydrogen phosphate was added to neutralize the reaction mixture. The precipitated solids were collected by filtration, washed with water and dried to give (2E)-3-[4-(4-fluorophenyl)-4H-1,2,4-triazol-3-yl]acrylic acid (3.60 g, yield 76%) as pale-yellow crystals. melting point: 226-229° C. (recrystallized from ethyl acetate-hexane).

출처