反应详情

A solution of 6-(2,4-difluorophenyl)imidazo[2,1-b]oxazole (30.0 g, 136 mmol), NIS (31.6 g, 140 mmol), and DMF (350 mL) was stirred at ambient temperature. After about 1 h, the reaction was poured into water (2 L) and the resulting precipitate was filtered, washing with additional water. The brown solid was dissolved in DCM and washed with saturated aqueous NaHCO3. The organic layer was dried over MgSO4, filtered, and concentrated under reduced pressure to dryness. The solid was dissolved in DCM, filtered through Florosil® and then concentrated under reduced pressure to a volume of about 0.5 L. The organic layer was washed with 5% aqueous NaS2O3, dried over MgSO4, filtered, and concentrated under reduced pressure to dryness to give the title compound as a yellow solid (34.5 g, 73%): LC/MS (Table 1, Method a) Rt=2.67 min; MS m/z: 346.9 (M+H)+.

1. filtrationthe resulting precipitate was filtered
2. washwashing with additional water
3. dissolutionThe brown solid was dissolved in DCM
4. washwashed with saturated aqueous NaHCO3
5. dry with materialThe organic layer was dried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure to dryness
8. dissolutionThe solid was dissolved in DCM
9. filtrationfiltered through Florosil®
10. concentrationconcentrated under reduced pressure to a volume of about 0.5 L
11. washThe organic layer was washed with 5% aqueous NaS2O3
12. dry with materialdried over MgSO4
13. filtrationfiltered
14. concentrationconcentrated under reduced pressure to dryness