[OH:1][C:2]1[CH:3]=[CH:4][CH:5]=[C:6]2[C:11]=1[N+:10]([O-])=[CH:9][CH:8]=[CH:7]2.[C:13]([O:16]C(=O)C)(=[O:15])[CH3:14].C(O)(=O)C>C1(C)C=CC=CC=1>[C:13]([O:16][C:9]1[CH:8]=[CH:7][C:6]2[C:11](=[C:2]([OH:1])[CH:3]=[CH:4][CH:5]=2)[N:10]=1)(=[O:15])[CH3:14]64 g (397 mmol) of 8-hydroxyquinoline N-oxide, 550 ml of acetic anhydride and 40 ml of acetic acid are placed in a 1 l round-bottomed flask. The reaction mixture is heated at reflux (135° C.) for 24 h, 40 ml of acetic acid are then again added and heating is continued for 1 h 30. The reaction mixture is allowed to return to ambient temperature and 400 ml of toluene are added. A precipitate appears and is filtered off. A further 400 ml of toluene are added and filtration is carried out. The precipitate is washed with 200 ml of ethyl ether and is dried in a desiccator under vacuum over phosphorus pentoxide to provide to provide 70.5 g of 2-acetoxy-8-hydroxyquinoline in the form of a brown solid. (Yield: 88%)
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