Water → HCID 10687030, compound

Participants

Reaction Steps

A solution of phosphorus oxychloride (2.05 g, 13.4 mmol) in dichloromethane (5.5 ml) was added during 20 minutes to a stirred solution of tert-butyl (4R)-4-(benzyloxycarbonylamino)-4-carbamoylbutyrate (3.0 g, 8.9 mmol) in dry pyridine (16 ml) at -5° C. under argon. The mixture was allowed to warm to room temperature and after 25 hours was poured into cold water (110 ml). The products were extracted with ethyl acetate (4×40 ml) and the combined ethyl acetate solution was washed successively with 10% aqueous citric acid solution (4×15 ml) and water (25 ml), then dried (Na2SO4) and evaporated. Toluene (4×25 ml) was added and evaporated and the residue was chromatographed with increasingly polar mixtures of hexane and ethyl acetate (100:0 to 2:1) as eluant to give tert-butyl (4R)-4-(benzyloxycarbonylamino)-4-cyanobutyrate (2.433 g, 86%) as a pale yellow oil.

Provenance & Evidence