[CH2:1]([O:3][C:4]([C:6]1[NH:15][C:9]2=[CH:10][N:11]=[C:12](Br)[CH:13]=[C:8]2[CH:7]=1)=[O:5])[CH3:2].[CH3:16][N:17](C=O)C>[C-]#N.[Zn+2].[C-]#N>[CH3:4][CH2:6][CH2:7][CH:8]([CH3:9])[CH3:13].[CH2:1]([O:3][C:4]([C:6]1[NH:15][C:9]2=[CH:10][N:11]=[C:12]([C:16]#[N:17])[CH:13]=[C:8]2[CH:7]=1)=[O:5])[CH3:2]To a solution of 5-bromo-1H-pyrrolo[2,3-c]pyridine-2-carboxylic acid ethyl ester (Preparation 26, 0.160 g, 0.590 mmol) in DMF (anhydrous, 5 mL) was added zinc (II) cyanide (0.041 g, 0.35 mmol) then tetrakis-triphenylphosphine palladium (0). The reaction mixture was degassed by bubbling argon through it for 10 min. The reaction mixture was heated to reflux temperature for 4.5 h then allowed to cool to rt. Water (30 mL) was added and the mixture extracted with ethyl acetate (2×50 mL). The combined organics were washed with brine (30 mL), dried (MgSO4), filtered and concentrated in vacuo. The residue was dissolved in ethyl acetate then adsorbed onto silica gel. Purification via flash column chromatography (SiO2, ethyl acetate: isohexane, 1:3, v/v) gave the title compound as a white solid. δH (CDCl3): 1.45 (3H, t), 4.49 (2H, quartet), 7.31 (1H, s), 8.09 (1H, s), 8.97 (1H, s), 9.60 (1H, br s); m/z (ES+)=216 [M+H]+; RT=3.03 min.
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