[Br:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][C:10]=1[CH3:11])[NH:7][C:6](C(O)=O)=[C:5]2[CH3:15].BrC1C(C)=C2C(=CC=1)NC(C(O)=O)=C2C.CCOCC.Cl>N1C2C(=CC=CC=2)C=CC=1.[Cu]>[Br:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][C:10]=1[CH3:11])[NH:7][CH:6]=[C:5]2[CH3:15]A 1:1 mixture of 5-bromo-3,6-dimethyl-1H-indole-2-carboxylic acid and 5-bromo-3,4-dimethyl-1H-indole-2-carboxylic acid (4.39 g, 16.4 mmol) in quinoline (10 mL) with copper powder (250 mg) was stirred at 240° C. for 3 h to give the corresponding mixture of the decarboxylated products. Upon cooling, ether (200 mL) was added and the mixture acidified with 5N HCl. The layers were separated, the organics were washed with brine, dried and evaporated. Chromatography (silica, 15% CH2Cl2 in hexane) and crystallization from a CH2Cl2/hexane mixture afforded the title compound (1.35 g 37%). 1H NMR (300 MHz, CDCl3). 7.74 (s, 1H), 7.21 (is, 1H), 6.90 (s, 1H), 2.48 (s, 3H), 2.27 (s, 3H).
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