Potassium Carbonate → 3-(Pyridin-4-ylamino)-1H-indole-2-carboxylic Acid 2-piperidin-1-yl-ethyl Ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Stir under N2 at 0° C. a mixture of 3-(4-pyridinylamino)-1H-indole-2-carboxylic acid (0.25 g, 1 mmol), benzotriazol-1-yloxytris(pyrrlidino)-phosphonium hexafluorophosphate (0.52 g, 1 mmol), diethylisopropylamine (0.175 mL, 1 mmol) and 1-methyl-2-pyrrolidinone (4.0 mL). Add 1-piperidineethanol (0.50 mL, 3.8 mmol) in one portion and stir at ambient temperature for 18.5 h. Pour the reaction into 5% aqueous potassium carbonate and extract with ethyl acetate (2×20mL). Wash the combined extract with water (20 mL), brine (20 mL), dry over MgSO4, filter and concentrate under vacuum to a dark residue. Chromatograph over silica gel (Redisep cartridge, 30 g) and elute with a step gradient of 10% methanol/dichloromethane (150 mL) to 20% methanol/dichloromethane. Concentrate like fractions under vacuum to an oil. Dry the oil under high vacuum at ambient temperature and obtain 0.14 g of the title compound as a tan foam: MS 365(M+H), TLC (silica gel, 0.5/9.5/90 ammonium hydroxide/methanol/dichloromethane) Rf=0.25.

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