Toluene → Benzyl (3S)-3-hydroxypyrrolidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A 0.5 g portion of (S)-3-hydroxypyrrolidine, as described in Example 42, was reconcentrated twice from toluene, dissolved in 80 ml of dichloromethane and cooled to 0° C. A 3.8 ml portion of triethylamine and 2.8 ml of benzylchloroformate were added with stirring. The reaction was stirred overnight, diluted with 300 ml of dichloromethane and extracted with 80 ml of 5% hydrochloric acid and 5% sodium bicarbonate solution. The aqueous phases were combined, saturated with sodium chloride and extracted with 3×150 ml of ethyl acetate. The organic phases were combined, dried, filtered and concentrated in vacuo. The residue was purified by chromatography (alumina) giving 940 g of (S)-3-hydroxy-1-pyrrolidinecarboxylic acid, phenylmethyl ester as a yellow oil [α]D26 =+21° (c, 1.054 methanol).

Provenance & Evidence