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

関与物質

反応手順

(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%).

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