反应详情

To a stirred solution of 2-(4-bromo-2-chlorophenyl)-1,3-oxazole (2.88 g, 11.14 mmol) in 1,4-dioxane (70 mL) were added tributhyl(1-ethoxyvinyl)tin (4.5 mL, 13.37 mmol), LiCl (1.18 g, 27.85 mmol) and tetrakis(triphenylphosphine)palladium(0) (1.28 g, 1.11 mmol) at room temperature under nitrogen. The mixture was heated at reflux temperature for 4 hours, and cooled down to room temperature, the solvent was removed under reduced pressure and the residue was dissolved in ethyl acetate (50 mL), washed with water (20 mL), dried over MgSO4 and concentrated in vacuo. The residue was dissolved in THF (30 mL) then 2N HCl (30 ml) was added at room temperature. After 2 hours, saturated NaHCO3 (100 mL) was added to the mixture. The mixture was extracted with ethyl acetate (300 mL) dried over MgSO4. Removal of the solvent, gave an oily residue, which was purified by flash chromatography eluting with ethyl acetate/hexane (1/4) to give title compound (1.891 g, 77% yield).

1. temperatureThe mixture was heated
2. temperatureat reflux temperature for 4 hours
3. customthe solvent was removed under reduced pressure
4. dissolutionthe residue was dissolved in ethyl acetate (50 mL)
5. washwashed with water (20 mL)
6. dry with materialdried over MgSO4
7. concentrationconcentrated in vacuo
8. dissolutionThe residue was dissolved in THF (30 mL)
9. addition2N HCl (30 ml) was added at room temperature
10. additionsaturated NaHCO3 (100 mL) was added to the mixture
11. extractionThe mixture was extracted with ethyl acetate (300 mL)
12. dry with materialdried over MgSO4
13. customRemoval of the solvent
14. customgave an oily residue, which
15. customwas purified by flash chromatography
16. washeluting with ethyl acetate/hexane (1/4)