Diisopropylethylamine → 4-{[4-(5-fluoro-benzofuran-3-ylmethoxy)-1H-indole-2-carbonyl]-amino}-piperidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-(5-fluoro-benzofuran-3ylmethoxy)-1H-indole-2-carboxylic acid (113, see example 60, 160 mg, 0.49 mmol) is dissolved in 1.5 ml of DMF and cooled to 0° C. After addition of Huenigs base (252 ul, 1.5 mmol) the mixture is stirred for 15 min, then piperidin-4-yl-carbamic acid tert-butyl ester (3, 98.5 mg, 0.49 mmol) is added, followed by PyBOP (269 mg, 0.51 mmol). The mixture is stirred at room temperature for 18 h. Then the mixture is diluted with ethyl acetate, washed 1N sodium hydroxide solution and brine. The organic layers are dried over sodium sulfate and evaporated under reduced pressure. The crude product (581 mg) is purified by flash-chromatography (silica gel, cyclohexane/ethyl acetate 1:1)

Provenance & Evidence