反应详情

温度

-40 °C

To a mixture of KOBu-t (450 mg, 4.2 mmol) and TosCH2NCO (410 mg, 2.1 mmol) in DME (8 ml) was added a solution of Compound 45 (350 mg, 2.0 mmol) in DME (2 ml) with cooling (-40° C.). The mixture was stirred at same temperature for 10 min. and then at room temperature for 1 h and to this was added MeOH (6 ml) dropwise. The mixture was stirred at same temperature for 1 hr. and then at room temperature for 15 h. The mixture was concentrated to give a solid, which was dissolved in water (10 ml). The aqueous layer was extracted with CH2Cl2. The combined extracts were dried (Na2SO4) and concentrated in vacuo to give crude product (480 mg) as a yellow oil. The crude product was purified by a column chromatography to give Compound 46 (230 mg, 1.2 mmol,. 60%) as a colorless solid.

1. waitat room temperature for 1 h
2. stirringThe mixture was stirred at same temperature for 1 hr
3. waitand then at room temperature for 15 h
4. concentrationThe mixture was concentrated
5. customto give a solid, which
6. extractionThe aqueous layer was extracted with CH2Cl2
7. dry with materialThe combined extracts were dried (Na2SO4)
8. concentrationconcentrated in vacuo
9. customto give crude product (480 mg) as a yellow oil
10. customThe crude product was purified by a column chromatography