Phosphorus oxychloride → HCID 58085779、化合物
反応式
[F:1][C:2]1[CH:3]=[CH:4][C:5]([C:12]([O:14][CH3:15])=[O:13])=[C:6]2[C:10]=1[O:9][C:8](=S)[NH:7]2.P(Cl)(Cl)(Cl)(Cl)[Cl:17].P(Cl)(Cl)(Cl)=O>>[Cl:17][C:8]1[O:9][C:10]2[C:6](=[C:5]([C:12]([O:14][CH3:15])=[O:13])[CH:4]=[CH:3][C:2]=2[F:1])[N:7]=1参加物
4
反応条件
- 温度
- 95 °C
実験手順
A mixture of methyl 7-fluoro-2-thioxo-2,3-dihydrobenzoxazole-4-carboxylate (1.3 g, 5.72 mmol) and phosphorus pentachloride (1.2 g, 5.72 mmol) in phosphorus oxychloride (2.6 mL, 10.25 mmol) was heated to 95° C. for 3.5 h. After cooling to room temperature, the reaction mixture was concentrated and dried under vacuum to afford methyl 2-chloro-7-fluorobenzoxazole-4-carboxylate (1.3 g, quantitative) as a brown solid. 1H NMR (300 MHz, CDCl3) δ 8.08-8.04 (m, 1H), 7.21 (t, J=9.3 Hz, 1H), 4.02 (s, 3H); MS (ESI+) m/z 229 (M+H).