CN(C=O)C.[C:6](Cl)(=[O:10])[C:7](Cl)=O.[NH:12]1[C:20]2[C:15](=[CH:16][CH:17]=[CH:18][C:19]=2[C:21]#[N:22])C=[CH:13]1>ClCCl>[CH:6]([C:7]1[C:15]2[C:20](=[C:19]([C:21]#[N:22])[CH:18]=[CH:17][CH:16]=2)[NH:12][CH:13]=1)=[O:10]DMF (0.539 mL) in dry dichloromethane (30 mL) was added dropwise to a solution of oxalyl chloride (0.610 mL) in dry dichloromethane (30 mL) at 0° C. The resulting solution was stirred at 0° C. for 15 min. A solution of 1H-indole-7-carbonitrile (D2) (0.90 g) in dry dichloromethane (5 mL) was added to the reaction mixture. The reaction mixture was warmed to RT and stirred for 30 min. The solvent was evaporated. THF (20 mL) was added, followed by addition of aqueous NaOH (0.5 M, 50 mL). The biphasic mixture was allowed to stand for 10 min. EtOAc (100 mL) and water (70 mL) was added. The organic fraction was separated and was dried over anhydrous magnesium sulfate. The dried solution was concentrated to afford 3-formyl-1H-indole-7-carbonitrile (D3) as a light cream solid (0.75 g, 70%). δH (DMSO-d6, 400 MHz): 7.42 (1H, t), 7.79 (1H, dd), 8.43 (1H, dd), 8.48 (1H, s), 10.00 (1H, s), 13.02 (1H, br s). MS (ES): C10H6N2O requires 170; found 171.2 (M+H+).
Wird geladen…
