反应详情

温度

20 °C

A solution containing 7.26 cm3 of DAST (diethylamino sulphide trifluoride) and 30 cm3 of methylene chloride is added at 5° C. to a solution containing 10 g of the product prepared in Stage A and 100 cm3 of methylene chloride. The reaction mixture is agitated at 20° C. for half an hour and is taken to reflux for 1 hour. It is maintained under agitation for 18 hours at 20° C. and taken to reflux for 3 hours, then treated with sodium acid carbonate and extracted with methylene chloride. After drying and concentrating, 12 g of a product is obtained which is chromatographed on silica eluting with a hexane--ethyl acetate mixture (8-2). In this way 5.5 g of desired product is obtained.

1. additionis added at 5° C. to a solution
2. temperatureto reflux for 1 hour
3. temperatureIt is maintained under agitation for 18 hours at 20° C.
4. temperatureto reflux for 3 hours
5. extractionextracted with methylene chloride
6. customAfter drying
7. concentrationconcentrating