Acetone → 1-tert-butyl 2-methyl (2S)-4-oxopyrrolidine-1,2-dicarboxylate

Participants

Reaction Steps

Methyl (2S,4R)—N-tert-butoxycarbonyl-4-hydroxy-2-pyrrolidinecarboxylate (2.00 g, 0.00815 mol) was dissolved in acetone (50.0 mL, 0.681 mol) and ether (50 mL). To the solution with stirring, was added a solution of chromium(VI) oxide (1.90 g, 0.0190 mol) in water (5.50 mL, 0.305 mol) and sulfuric acid (1.60 mL, 0.0294 mol) over 15 minutes with the presence of an ice-water bath to maintain the reaction temperature at about room temperature. The mixture was stirred at rt for 10 minutes and then iso-propanol (10 mL) was added. The mixture was stirred for an additional 5 min. The mixture was filtered through a pad of silica gel plus potassium carbonate. The filtrated was concentrated and the residue was purified by Combiflash with ethyl acetate/hexane (25%) to give the desired product (1.12 g).

Provenance & Evidence