反应详情

温度

-10 °C

The product from Example 68A (0.63 g, 1.6 mmol) in chloroform (10 mL) under a nitrogen atmosphere was treated with pyridine (0.16 mL, 1.9 mmol) and pyridinium tribromide (0.57 g, 1.8 mmol) at −10° C. After stirring at −10° C. for 2 hours, the mixture was allowed to warm to ambient temperature and then was treated with 1M HC1 and extracted with chloroform. The chloroform layer was dried (MgSO4), filtered, concentrated, heated to 130° C. under nitrogen for 1 hour and cooled to ambient temperature. Purification of the residue by chromatography on silica gel eluting with 10% methanol in dichloromethane provided the title compound (0.30 g).

1. temperatureto warm to ambient temperature
2. additionwas treated with 1M HC1
3. extractionextracted with chloroform
4. dry with materialThe chloroform layer was dried (MgSO4)
5. filtrationfiltered
6. concentrationconcentrated
7. temperatureheated to 130° C. under nitrogen for 1 hour
8. temperaturecooled to ambient temperature
9. customPurification of the residue by chromatography on silica gel eluting with 10% methanol in dichloromethane