1196107-73-9

1196107-72-8

1196107-73-9

General procedure: 2-Bromo-9,9-dimethyl-7-(2-carboxybenzoyl)fluorene (20 g, 0.047 mol, 1 eq.) was used as a raw material, which was placed in a reaction flask and polyphosphoric acid (50 ml) was added. The reaction mixture was heated to 140 °C for the reaction. After completion of the reaction, the resulting solid product was filtered, washed with a small amount of methanol and then dried to afford the target compound 2-bromo-13,13-dimethyl-6H-indeno[1,2-b]anthracene-6,11(13H)-dione (16.6 g, 81% yield). The product was characterized by 1H-NMR: δ 8.29 (t, 2H), 8.09 (s, 2H), 7.85 (d, 2H), 7.72 (m, 3H), 1.67 (s, 6H).