反应详情

A flame-dried round bottom flask was charged with 80 (4.37 g, 9.48 mmol) and glacial acetic acid (61 mL). The flask was sealed with a septum and flushed with nitrogen. Zinc-copper couple (6.07 g, Aldrich) was added and the reaction stirred at room temperature for a period of 21 h. The reaction was then heated to 80° C. for 1 h. The reaction mixture was cooled to room temperature, filtered thru a pad of Celite®, washed with EtOAc (200 mL) and concentrated under vacuum. The resulting white solid (residue) was diluted with CH2Cl2 (250 mL) and washed with 0.5 M NaOH (500 mL). The aqueous layer was extracted with CH2Cl2 (2×150 mL) and the combined organic layers were dried (MgSO4), filtered and concentrated. Purification by flash chromatography (SiO2, 5% Acetone-CH2Cl2) afforded 78 (3.64 g, 90%) as a white powder identical in all respects to material isolated in Example 38, step 2.

1. customThe flask was sealed with a septum
2. customflushed with nitrogen
3. additionZinc-copper couple (6.07 g, Aldrich) was added
4. temperatureThe reaction was then heated to 80° C. for 1 h
5. temperatureThe reaction mixture was cooled to room temperature
6. filtrationfiltered
7. washwashed with EtOAc (200 mL)
8. concentrationconcentrated under vacuum
9. additionThe resulting white solid (residue) was diluted with CH2Cl2 (250 mL)
10. washwashed with 0.5 M NaOH (500 mL)
11. extractionThe aqueous layer was extracted with CH2Cl2 (2×150 mL)
12. dry with materialthe combined organic layers were dried (MgSO4)
13. filtrationfiltered
14. concentrationconcentrated
15. customPurification by flash chromatography (SiO2, 5% Acetone-CH2Cl2)