[Br:1][C:2]1[CH:3]=[C:4]2[C:9](=[O:10])[O:8][C:6](=O)[C:5]2=[CH:11][CH:12]=1.[CH2:13](N(CC)CC)C.C(OCC)(=O)CC(C)=O.Cl>C(OC(=O)C)(=O)C>[Br:1][C:2]1[CH:3]=[C:4]2[C:5](=[CH:11][CH:12]=1)[C:6](=[O:8])[CH2:13][C:9]2=[O:10]A solution of 4-bromo phthalic anhydride (4.15 g; 0.018 mole) in acetic anhydride (10 g) containing triethylamine (4 g) was treated at room temperature with ethyl acetoacetate (2.38 g; 0.02 mole). After 24 hrs. with stirring, crushed ice (20 g) and concentrated hydrochloric acid (10 ml) were added and the precipitated red solid filtered. Addition of a hot (70°-80°C) solution of hydrochloric acid (150 ml) in water (750 ml) to this solid resulted in decarboxylation and generation of 5-bromo indane-1,3-dione as red plates, m.p. (acetone) 152°-3°C. (Found; C, 48.04; H, 2.17; Br, 35.63; C9H5Br O2 requires; C, 48.05; H, 2.24; Br, 35.52%).
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