Acetic-formic anhydride → 7-Methoxy-3-nitro-4H-1-benzopyran-4-one
反応式
[OH:1][C:2]1[CH:7]=[C:6]([O:8][CH3:9])[CH:5]=[CH:4][C:3]=1[C:10](=[O:15])[CH2:11][N+:12]([O-:14])=[O:13].[CH:16](OC(=O)C)=O>O>[N+:12]([C:11]1[C:10](=[O:15])[C:3]2[CH:4]=[CH:5][C:6]([O:8][CH3:9])=[CH:7][C:2]=2[O:1][CH:16]=1)([O-:14])=[O:13]参加物
4
反応条件
- 温度
- 80 °C
実験手順
3-Nitro-7-methoxy-4H-1-benzopyran-4-one was prepared by the addition of 1-(2-hydroxy-4-methoxyphenyl)-2nitro ethanone (2.11 g, 0.01m), prepared in Example 8, and sodium formate (0.68 g, 0.01m) to stirred acetic-formic anhydride (25 ml). The reaction was warmed to 80° C. and allowed to return to room temperature. After stirring at least an additional 1 hour, cold water (100 ml) was added. The product was filtered off, washed with fresh portions of water and sucked dry. Recrystallization from ethyl acetate gave yellow crystals (1.7 g, 77.5%), m.p. 185°-87° C.