Acetic Acid → 6-Ethylisatoic anhydride
Reaktionsgleichung
C([C:3]1[CH:4]=[C:5]2[C:9](=[CH:10][CH:11]=1)[NH:8][C:7](=[O:12])[C:6]2=O)C.S(=O)(=O)(O)O.OO.[C:21]([OH:24])(=[O:23])[CH3:22]>>[CH2:5]([C:4]1[CH:3]=[CH:11][CH:10]=[C:9]2[NH:8][C:7](=[O:12])[O:24][C:21](=[O:23])[C:22]=12)[CH3:6]Komponenten
5
Versuchsvorschrift
5-Ethylisatin (70 g), acetic acid (200 ml) and concentrated sulfuric acid (0.8 ml) were charged in a 500 ml two-necked flask, followed by stirring at room temperature. Then, 50 ml of aqueous 30% hydrogen peroxide was added dropwise and, after stirring at 60° to 65° C. for additional one hour, the mixture was cooled. The deposited solid was filtered, washed with water and dried under vacuum to obtain 6-ethylisatoic anhydride. Crude yield: 35 g