反应详情

To a solution of 2-(3,4-dimethoxy-5-nitrophenyl)-2-oxoethyl acetate (4.24 g, 15 mmol) in xylene (30 mL) were added 2-(trifluoromethyl)nicotinamide (3.135 g, 16.5 mmol) and boron trifluoride etherate (0.18 mL, 15 mmol). The resulting yellow solution was heated to reflux for 18 hours and then cooled to room temperature. After evaporation of the solvent, the residue was partitioned between ethyl acetate and saturated aqueous sodium bicarbonate. The organic phase was separated, washed with brine and the dried over anhydrous magnesium sulphate, filtered and evaporated. The pure 4-(3,4-dimethoxy-5-nitrophenyl)-2-(2-(trifluoromethyl)pyridin-3-yl)oxazole was obtained by column chromatography over silica gel (petroleum ether/ethylacetate 2:1) as a pale yellow solid, 2.488 g (42%).

1. temperatureThe resulting yellow solution was heated
2. temperatureto reflux for 18 hours
3. customAfter evaporation of the solvent
4. customthe residue was partitioned between ethyl acetate and saturated aqueous sodium bicarbonate
5. customThe organic phase was separated
6. washwashed with brine
7. dry with materialthe dried over anhydrous magnesium sulphate
8. filtrationfiltered
9. customevaporated