Diisopropylethylamine → N-((1R)-1-(N-(2-(2-(methylsulfonylamino)phenyl)ethyl)-N-methylcarbamoyl)-2-(2-naphthyl)ethyl)-N-methylcarbamic acid tert-butyl-ester

Participants

Reaction Conditions

Reaction Steps

(2R)-2-(N-(tert-Butoxycarbonyl)-N-methylamino)-3(2-naphthyl)propionic acid (444 mg, 1.35 mmol) and successively 1-hydroxy-7-azabenzotriazole (184 mg, 1.35 mmol) were dissolved in N,N-dimethylformamide (5 ml) and dichloromethane (7 ml). The solution was cooled to 0° C. N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (259 mg, 1.35 mmol) was added. The reaction mixture was stirred for 15 min at 0° C. A solution of N-(2-(2-(methylamino)ethyl)phenyl)methanesulfonamide (308 mg, 1.35 mmol) was added. Ethyldiisopropylamine (0.23 ml, 1.35 mmol) was added. The reaction mixture was stirred for 16 h, while it was warming up to room temperature. It was diluted with ethyl acetate and washed with 10% aqueous sodium hydrogen sulfate solution (70 ml). The aqueous phase was extracted with ethyl acetate (2×50 ml). The combined organic layers were washed with a saturated aqueous solution of sodium hydrogen carbonate (150 ml) and dried over magnesium sulfate. The solvent was removed in vacuo. The crude product was purified by flash chromatography on silica (60 g), using ethyl acetate/heptane (1:1) as eluent, to give 245 mg of N-((1R)-1-(N-(2-(2-(methylsulfonylamino)phenyl)ethyl)-N-methylcarbamoyl)-2-(2-naphthyl)ethyl)-N-methylcarbamic acid tert-butyl-ester.

Provenance & Evidence