反应详情

A solution of benzyl trifluoroacetyl-L-serinate (500 mg) and diketene (0.1 ml) in tetrahydrofuran (10 ml) was heated with reflux overnight. The solvent was distilled off and the residue was diluted with ethyl acetate and washed successively with water and brine. After drying over sodium sulfate, the ethyl acetate extract was filtered and concentrated. The residue was chromatographed on silica gel eluting successively with methylene chloride and a 4:1 mixture of methylene chloride and acetone to give benzyl O-acetoacetyl-N-trifluoroacetyl-L-serinate (320 mg).

1. temperaturewith reflux overnight
2. distillationThe solvent was distilled off
3. additionthe residue was diluted with ethyl acetate
4. washwashed successively with water and brine
5. dry with materialAfter drying over sodium sulfate
6. extractionthe ethyl acetate extract
7. filtrationwas filtered
8. concentrationconcentrated
9. customThe residue was chromatographed on silica gel eluting successively with methylene chloride
10. additiona 4:1 mixture of methylene chloride and acetone