反应详情

温度

105 °C

A mixture of 420 g of 19c and 500 mg of sodium acetate and 8 ml of acetic anhydride was heated at 105° C. for 3 h. The reaction mixture was cooled and diluted with 20 ml of water and stirred for 1 h to decompose the acetic anhydride. Then a solution of cold conc. ammonia was added to pH 8. The product was extracted with ethyl acetate. The organic layer was washed, dried, concentrated and the crude material was chromatographed over silica gel, using a gradient of heptane/ethyl acetate as eluent. The material thus isolated was treated with heptane/diisopropyl ether (1/1) to provide 95 mg of 19d as white crystalline material; Mp 127-129° C.

1. temperatureThe reaction mixture was cooled
2. extractionThe product was extracted with ethyl acetate
3. washThe organic layer was washed
4. customdried
5. concentrationconcentrated
6. customthe crude material was chromatographed over silica gel
7. customThe material thus isolated