ethyl(4S)-4-{[(benzyloxy)carbonyl]amino}-3-(tert-butyldimethylsilyloxy)hexanoate → (4R,5S)-4-(tert-butyldimethylsilyloxy)-5-ethylpyrrolidin-2-one

Participants

Reaction Steps

To a solution of ethyl(4S)-4-{[(benzyloxy)carbonyl]amino}-3-(tert-butyldimethylsilyloxy)hexanoate (64.0 g) in methanol (500 mL) was added 10% palladium carbon (containing 50% water, 6.5 g), and the mixture was stirred at room temperature for 3.5 hr under a hydrogen atmosphere and filtered. Sodium methoxide (13.6 g) was added to the filtrate, and the mixture was stirred at room temperature for 2 hr. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The extract was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: hexane/ethyl acetate=20/1→1/4) to give the title compound (yield: 21.6 g, 59%) and (4S,5S)-4-(tert-butyldimethylsilyloxy)-5-ethylpyrrolidin-2-one (yield: 4.64 g, 13%) as a colorless solid and a colorless oil, respectively.

Provenance & Evidence