反应详情

温度

110 °C

To a suspension of the compound 19 (77.6 mg, 0.200 mmol) in acetic anhydride (1 mL) was added conc. sulfuric acid (0.24 eq.), and heated with reflux at 110° C. for 1 hour. Triethylamine (0.1 mL) was added to the reaction mixture, and the mixture was concentrated under reduced pressure. The residue was purified by chromatography on a silica gel column (eluate: ethyl acetate) to give the compound 80 (31 mg, 35%) as crystals. Mp. 163-164° C. (hexane-ether) Rf 0.10 (1:2 EtOAc - hexane)

1. temperatureheated
2. concentrationthe mixture was concentrated under reduced pressure
3. customThe residue was purified by chromatography on a silica gel column (eluate: ethyl acetate)