Water → HCID 58298436, compound

Participants

Reaction Conditions

Reaction Steps

A suspension of 27 g of lithium borohydride in 15 mL of anhydrous tetrahydrofuran is cooled to 10° C. and a solution of 15.4 g of (2S,4S)-4-isopropyl-5-oxo-pyrrolidine-1,2-dicarboxylic acid-2-benzyl ester-1-tert-butyl ester in 80 mL of tetrahydrofuran is added within 2 hours. The resulting suspension is warmed to 40° C. and stirred for a further 3 hours. Water (800 mL) is then added and the mixture filtered. The solid is then suspended in 700 mL of tetrahydrofuran and heated to reflux for 75 minutes. After this time the mixture is cooled to 25° C. and filtered. The filtrate is treated slowly with 500 mL of a 1.0 M solution of oxalic acid in water at room temperature. The resulting suspension is filtered and the solid washed with 500 mL of tetrahydrofuran. The solvent is then removed from the filtrate to provide an oil. The oil is re-dissolved in a mixture of 630 mL of ethyl acetate and 0.07 L of ethanol at elevated temperature and the slightly cloudy solution filtered. The clear solution is cooled to −25° C. and the resulting suspension stirred for 2 hours. The solid is collected by filtration, washed with ethyl acetate and dried to give (3S,5S)-5-hydroxymethyl-3-isopropyl-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester.

Provenance & Evidence