1,2-Dichloroethane → tert-butyl 1-((S)-2-carbamoylpyrrolidin-1-yl)-5-((S)-2-(methoxymethyl)pyrrolidin-1-yl)-1,5-dioxopentan-2-ylcarbamate

Participants

Reaction Steps

To a mixture of 2-tert-butoxycarbonylamino-5-((S)-2-methoxymethyl-pyrrolidin-1-yl)-5-oxo-pentanoic acid (0.34 g, 1 mmol), L-prolinamide (0.11 g, 1 mmol), and HOBt hydrate (0.14 g, 1 mmol) in CH2Cl2 (5 mL) was added EDC (0.19 g, 1 mmol). The reaction mixture was stirred at ambient temperature for 12 h, diluted with CH2Cl2 (20 mL), washed sequentially with saturated aqueous sodium bicarbonate (10 mL), 0.5 N aqueous citric acid (10 mL) and brine (10 mL), dried over magnesium sulfate, filtered, and concentrated under reduced pressure to yield a crude a viscous oil. The crude oil was purified by flash chromatography (silica gel, 2 to 8% CH3OH/CH2Cl2 gradient) to give the title compound (0.36 g, 81%) as a foamy solid.

Provenance & Evidence