Phosphorus oxide (P4O10) → 2-(2-Chloro-5-nitrophenyl)oxazole
反応式
O=P12OP3(OP(OP(O3)(O1)=O)(=O)O2)=O.[Cl:15][C:16]1[CH:30]=[CH:29][C:28]([N+:31]([O-:33])=[O:32])=[CH:27][C:17]=1[C:18]([NH:20][CH2:21][CH:22]([O:25]C)OC)=O>CS(O)(=O)=O>[Cl:15][C:16]1[CH:30]=[CH:29][C:28]([N+:31]([O-:33])=[O:32])=[CH:27][C:17]=1[C:18]1[O:25][CH:22]=[CH:21][N:20]=1参加物
4
反応条件
- 温度
- 142.5 °C
実験手順
Under nitrogen, phosphorus pentoxide (0.98 g, 6.90 mmol) was added portionwise to a slurry of 2-chloro-N-(2,2-dimethoxy-ethyl)-5-nitro-benzamide (0.5 g, 1.73 mmol) in methanesulfonic acid (5 mL) at r.t. The mixture was heated to 140-145° C. for 6 h. After cooling to r.t., the mixture was poured onto ice-water and extracted with ethyl acetate. The combined organic phases were washed with water then brine, dried over sodium sulfate, filtered and concentrated in vacuo. Further drying under high vacuum gave 2-(2-chloro-5-nitrophenyl)-oxazole (0.366 g, 94%) as a solid.