Tert-butyl 3-oxopyrrolidine-1-carboxylate → HCID 69694946, compound

Participants

Reaction Conditions

Reaction Steps

To a well-stirred solution of the title compound of Example 1, Step 1 (2.10 g, 8.9 mmol) in 30 ml of anhydrous tetrahydrofuran chilled to and maintained at −77° C., a 2.5 M solution of n-butyl lithium in hexanes (3.60 ml, 8.9 mmol; Aldrich Chemical Co.) is added dropwise over a 10 minute period. The reaction was stirred at −77° C. for 15 minutes before adding a solution of 3-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester (1.65 g, 8.9 mmol) in anhydrous tetrahydrofuran (10 ml). The reaction mixture was allowed to warm to ambient temperature and stir at that temperature for 3 hours before quenching by cautious dropwise addition (with cooling) of saturated aqueous sodium bicarbonate (50 ml total). The resulting mixture was thoroughly extracted with three 20 ml of ethyl acetate. The combined organic extracts were, in turn, extracted with an equal volume portion of brine, dried (anhydrous sodium sulfate) and, finally, concentrated in vacuo, yielding a viscous syrup. Flash chromatography of the entire sample (silica gel, 47-61 micron mesh; elution with methylene chloride/methanol=98:2 in volume) afforded the title compound (352 mg, 11.5% yield) as a viscous yellow oil.

Provenance & Evidence