反应详情

The product from 11a (12.9 g; 46.3 mmol) was added in portions to a stirred mixture of sodium borohydride (1.70 g; 45.0 mmol) in dry tetrahydrofuran (25 mL). After the evolution of hydrogen subsided, a solution of boron trifluoride dimethyl etherate (4.6 mL; 5.7 g; 50 mmol) in dry tetrahydrofuran (15 mL) was added drop-wise. The exothermic reaction was moderated with a cold water bath. After stirring 4 h at ambient temperature, the reaction mixture was hydrolyzed with cold water (20 mL). The mixture was separated and the organic phase was evaporated; the residue was mixed with water (20 mL) and dichloromethane (70 mL) to give an emulsion that separated on standing overnight. The organic layer was washed with water (4×15 mL) until the washings were neutral to pH paper. Following drying (Na2SO4), filtration, and evaporation 11.95 g (98%) product was obtained (oil).

1. customThe exothermic reaction
2. customwas moderated with a cold water bath
3. customThe mixture was separated
4. customthe organic phase was evaporated
5. additionthe residue was mixed with water (20 mL) and dichloromethane (70 mL)
6. customto give an emulsion that
7. customseparated
8. waiton standing overnight
9. washThe organic layer was washed with water (4×15 mL) until the washings
10. customFollowing drying
11. filtration(Na2SO4), filtration
12. customevaporation 11.95 g (98%) product
13. customwas obtained (oil)