Toluene → 4-(hydroxymethyl)-2-[(E)-2-[4-(trifluoromethyl)phenyl]ethenyl]-1,3-oxazole

(E)-3-(4-(Trifluoromethyl)phenyl)-2-propenamide (4.30 g, 20.0 mmol) and 1,3-dichloroacetone (4.75 g, 37.4 mmol) were added to toluene (20 ml) and the mixture was subjected to refluxing azeotropic dehydration using a Dean-Stark tube for 6 hours. The reaction mixture was allowed to cool to room temperature, and DMF (50 ml), water (30 ml) and potassium carbonate (13.7 g, 99.1 mmol) were added. The mixture was stirred at 100° C. for 1.5 hours. After allowing to cool to room temperature, ethyl acetate (200 ml) and water (150 ml) were added and the mixture was partitioned. The organic layer was washed with water/saturated brine (1:1, 100 ml). To the organic layer was added ethyl acetate (400 ml), and the mixture was washed with water (200 ml) twice and concentrated under reduced pressure. Ethanol (30 ml) was added to the residue. Water (38 ml) was added and the precipitated crystals were collected by filtration, washed with water (40 ml) and dried under reduced pressure to give 4-(hydroxymethyl)-2-[(E)-2-[4-(trifluoromethyl)phenyl]ethenyl]-1,3-oxazole (3.3 g, 3.71 mmol, yield 62%).

1. temperatureto refluxing azeotropic dehydration
2. customfor 6 hours
3. temperatureto cool to room temperature
4. customthe mixture was partitioned
5. washThe organic layer was washed with water/saturated brine (1:1, 100 ml)
6. additionTo the organic layer was added ethyl acetate (400 ml)
7. washthe mixture was washed with water (200 ml) twice
8. concentrationconcentrated under reduced pressure
9. additionEthanol (30 ml) was added to the residue
10. additionWater (38 ml) was added
11. filtrationthe precipitated crystals were collected by filtration
12. washwashed with water (40 ml)
13. customdried under reduced pressure

ORD-Eintrag

ord-0a8d5c38ed564c68853174856e713334

Quelldatensatz

uspto-grants-2004_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06743924B2