Diisopropylethylamine → N-(2-(5-chloro-1H-indol-3-yl)ethyl)-4-phenylisoxazole-3-carboxamide

Participants

Reaction Steps

A mixture of ethyl 4-phenylisoxazole-3-carboxylate (0.030 g; 0.130 mmol) in THF (1 mL) and sodium hydroxide in water (2M, 1 mL) was stirred at room temperature for 2.5 hours. The reaction mixture was then diluted with water and the aqueous layer was extracted with dichloromethane. The aqueous layer was acidified with HCl 6N until pH 2 and extracted with ethyl acetate. The organic layer was dried over magnesium sulphate and concentrated under reduced pressure. The crude residue was added to a mixture of 2-(5-chloro-1H-indol-3-yl)ethanamine hydrochloride (0.030 g; 0.130 mmol), HATU (0.50 g; 0.130 mmol), N,N diisopropylethylamine (0.055 mL; 0.324 mmol), in DMF (2 mL) and was stirred at room temperature for 72 hours. The reaction mixture was diluted with ethyl acetate and was washed with sodium hydrogensulphate, sodium carbonate and brine. The organic layer was dried over magnesium sulphate and concentrated under reduced pressure. The crude material was purified by flash chromatography on silica (eluent 20 to 100% ethyl acetate in heptane) and then by preparative HPLC method 2 to yield 0.0136 g (30%) of the title compound as a white solid.

Provenance & Evidence