Reacción #452138

Ecuación de reacción

Ethyl 4,4-diethoxy-2-(3-nitrophenylmethylene)-3-oxobutanoate

ethyl 3-amino-4-fluoro-2-butenoate

→

title compound

Rendimiento 18.3%

Diethyl 2-(fluoromethyl)-6-formyl-1,4-dihydro-4-(3-nitrophenyl)-3,5-pyridinedicarboxylate

Rendimiento 18.3%

Disolventes

ethyl acetate

Condiciones de reacción

Tratamiento posterior

1. 1
   Lavadowashed with water and saturated brine
2. 2
   Secadodried (MgSO4)
3. 3
   Otrothe solvent was removed in vacuo
4. 4
   workup.DISSOLUTIONThe residue was dissolved in tetrahydrofuran (195 ml)
5. 5
   workup.ADDITION50% aqueous hydrochloric acid (292 ml) was added slowly
6. 6
   ExtracciónAfter 30 minutes the reaction mixture was extracted with ethyl acetate
7. 7
   Extracciónthe organic extract
8. 8
   Lavadowashed with saturated aqueous sodium bicarbonate, water
9. 9
   Secadodried (MgSO4)
10. 10
    Otrothe solvent was removed in vacuo
11. 11
    OtroThe residue was chromatographed on silica eluting with ethyl acetate/petroleum ether (60°-80°) mixtures
12. 12
    OtroCrystallisation from 2-propanol

Procedimiento

Ethyl 4,4-diethoxy-2-(3-nitrophenylmethylene)-3-oxobutanoate (21.75 g, 62 mmoles) and ethyl 3-amino-4-fluoro-2-butenoate (9.17 g, 68 mmoles) were heated at 125° for 1.5 hours. The reaction mixture was dissolved in ethyl acetate (150 ml), washed with water and saturated brine, dried (MgSO4) and the solvent was removed in vacuo. The residue was dissolved in tetrahydrofuran (195 ml) and 50% aqueous hydrochloric acid (292 ml) was added slowly. After 30 minutes the reaction mixture was extracted with ethyl acetate and the organic extract washed with saturated aqueous sodium bicarbonate, water, dried (MgSO4) and the solvent was removed in vacuo. The residue was chromatographed on silica eluting with ethyl acetate/petroleum ether (60°-80°) mixtures. Crystallisation from 2-propanol gave the title compound (4.6 g), mp 88°-90°.

Fuente