Triethylamine → HCID 13067887, compound

Participants

Reaction Steps

Benzyl chloroformate (7.9 g.) was dissolved in methylene chloride (50 ml.). A methylene chloride (20 ml.) solution containing 3-amino-1-(1-methoxycarbonyl-2-methyl-1-propenyl)-2-azetidinone (2.42 g.) and triethylamine (3.7 g.) was added dropwise to the solution at -15° to -10° C. in the course of 1.33 hours with stirring, whereafter the mixture was stirred at the same temperature for 1.25 hours. The reaction mixture was evaporated to dryness under reduced pressure to give a residue, which was dissolved in ethyl acetate (150 ml.). The solution was washed three times with 5% hydrochloric acid and once with an aqueous sodium chloride, and then dried over magnesium sulfate. The solvent was removed by distillation and a residue (7.3 g.) was treated with n-hexane to give crude object compound, 3-benzyloxycarbonylamino-1-(1-methoxycarbonyl-2-methyl-1-propenyl)-2-azetidinone (3.27 g.). The compound (3.71 g.) thus obtained was subjected to column chromatography on silica gel (60 g.), and elution was carried out with chloroform and a mixture of chloroform and methanol (volume ratio; 10:1). The fractions containing the desired compound were collected and the solvent was distilled off from the eluate under reduced pressure to give the purified object compound (3.05 g.).

Provenance & Evidence