Réaction #8570

Équation de réaction

water

potassium hydroxide

(2S)-2-(2,3,4-trifluoroanilino)propanol

diethylethoxymethylenemalonate

→

title compound

Rendement 90.2%

Diethyl [2,3,4-trifluoro[(1S)-2-hydroxy-1-methylethyl]anilino]methylenemalonate

Rendement 90.2%

Solvants

DMF

DMF

Conditions de réaction

Traitement

1. 1
   Autrethe liquid reaction mixture
2. 2
   Extractionwas extracted with a solvent mixture of ethyl acetate and n-hexane (3:2)
3. 3
   LavageThe organic layer was washed with water
4. 4
   Séchagedried over anhydrous magnesium sulfate
5. 5
   AutreAfter evaporating the solvent, IPE
6. 6
   workup.ADDITIONwas added to the obtained residue
7. 7
   AutreThe crystals thus precipitated
8. 8
   Filtrationwere collected by filtration
9. 9
   Autrethe moist product thus obtained
10. 10
    Autrewas dried under reduced pressure

Mode opératoire

At room temperature, potassium hydroxide (330 mg) and tetrabutylammonium hydrogensulfate (82.7 mg) were dissolved in DMF (15 ml). After adding a solution (5 ml) of (2S)-2-(2,3,4-trifluoroanilino)propanol (1 g, 99.8% ee) and diethylethoxymethylenemalonate (2.09 g) in DMF, the resultant mixture was stirred for 1 hour. After adding water, the liquid reaction mixture was extracted with a solvent mixture of ethyl acetate and n-hexane (3:2). The organic layer was washed with water and dried over anhydrous magnesium sulfate. After evaporating the solvent, IPE was added to the obtained residue and the mixture was stirred at 0° C. for 1 hour. The crystals thus precipitated were collected by filtration and the moist product thus obtained was dried under reduced pressure. Thus, the title compound (1.65 g, 99. 8% ee) was obtained as colorless crystals. The 1H-NMR and IR spectral data of this product was identical with those of the compound obtained in Example 63.

Source