N-(1-Ethoxycarbonylbutyl)-L-alanine benzyl ester → (2S)-2-[[(2S)-1-ethoxy-1-oxopentan-2-yl]amino]propanoic acid

Participants

Reaction Steps

The S,S diastereoisomer benzylester from step (b) (6.2g) in ethanol (250ml) was hydrogenated at 3 atmospheres at room temperature for 30 minutes over 10% palladium on charcoal (0.6g). The catalyst was removed by filtration and the filtrate was evaporated to near dryness. The residue was slurried with diethyl ether and the white solid was filtered off and was dried to give the required product (3.8g) mp 153°-4°.

Provenance & Evidence