Diisopropylethylamine → N-{N-[(5-tert-butoxycarbonylthiophen-2-yl)methyl]-N-methyl-L-leucyl}-L-aspartic acid dimethyl ester

Participants

Reaction Steps

The compound (0.20 g, 0.58 mmol) obtained in step 2, aspartic acid dimethyl ester hydrochloride (0.12 g, 0.58 mmol), WSC hydrochloride (0.17 g, 0.87 mmol), 1-hydroxybenzotriazole monohydrate (0.090 g, 0.58 mmol), and N,N-diisopropylethylamine (0.39 mL, 2.8 mmol) were dissolved in dichloromethane (5 mL), and the mixture was stirred at room temperature for 2 hours. The reaction mixture was concentrated under reduced pressure, and ethyl acetate was added. The mixture was washed with saturated aqueous sodium hydrogen carbonate and saturated brine, and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure and the obtained residue was purified by silica gel column chromatography (hexane/ethyl acetate) to give the title compound (0.15 g, 0.31 mmol, 53%).

Provenance & Evidence