Allyl chloroformate → HCID 86760498, compound

Participants

Reaction Steps

tert-Butyl (S)-3-[(tert-butyl)oxycarbonylamino]-4-oxo-4-(2,2,2-trichloroethoxy)butyrate (605 mg, 1.48 mmol) obtained from Example 20-(1) was dissolved in trifluoroacetic acid (2.5 ml) followed by stirring for 1 hour. The mixture was diluted with toluene, and the solvent was distilled off under reduced pressure. The obtained white powder was suspended in dichloromethane (5 ml), and diisopropylethylamine (1.8 ml, 10 mmol) and allyl chloroformate (624 mg, 5.18 mmol) were added thereto at room temperature. The mixture was stirred for 1 hour, then a saturated aqueous solution of ammonium chloride was added thereto, and the product was extracted with ethyl acetate. The organic layer was washed successively with water and an aqueous solution of sodium chloride, dried over anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure. The residue was subjected to chromatography on a silica gel (25 g) column (eluent; hexane:ethyl acetate=4:1) to afford the title compound (384 mg, 67% yield) as a colorless oil.

Provenance & Evidence