反应详情

温度

25 °C

To a solution of the product from Example 1B (7.32 g, 12.1 mmol) in toluene (400 mL) were treated with DPPA (5.2 mL, 24.2 mmol) and triethylamine (3.4 mL, 24.4 mmol), heated at reflux for 2 hours, cooled, treated with tert-Butyl alcohol (41.6 mL), triethylamine (4 mL), and DMAP (0.30 g), heated at reflux for an additional 64 hours, cooled and concentrated. A solution of the residue in THF (60 mL) was treated with TBAF solution in THF (36 mL, 1N), stirred at 25° C. for 40 hours, concentrated and partitioned between ethyl acetate and water. The organic phase was washed with brined, dried over MgSO4, filtered and concentrated. The residue was chromatographed on silica gel eluting with 0-50% ethyl acetate in dichloromethane to give 0.614 g (9% yield) of the lower Rf product by TLC (25% ethyl acetate in dichloromethane).

1. temperatureheated
2. temperatureat reflux for 2 hours
3. temperaturecooled
4. temperatureheated
5. temperatureat reflux for an additional 64 hours
6. temperaturecooled
7. concentrationconcentrated
8. additionA solution of the residue in THF (60 mL) was treated with TBAF solution in THF (36 mL, 1N)
9. concentrationconcentrated
10. custompartitioned between ethyl acetate and water
11. washThe organic phase was washed with brined,
12. dry with materialdried over MgSO4
13. filtrationfiltered
14. concentrationconcentrated
15. customThe residue was chromatographed on silica gel eluting with 0-50% ethyl acetate in dichloromethane
16. customto give 0.614 g (9% yield) of the lower Rf product by TLC (25% ethyl acetate in dichloromethane)