反应详情

2-(2-Ethoxycarbonylethyl)-3,4-dihydro-1(2H)-naphthalenone (19.7 g, 80 mmol), from Step 1, was dissolved in 200 mL of dry THF and diethyl cyanophosphonate (23.6 mL, 160 mmol), commercially available from Aldrich Chemical Company, was added, followed by 160 mL of a 0.5M solution of lithium cyanide in DMF. The reaction mixture was stirred at ambient temperature overnight and then poured into water. The aqueous mixture was extracted with three portions of diethyl ether. The ether extracts were dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was dissolved in 400 mL of toluene and 20 g of p-toluenesulfonic acid was added. The reaction mixture was heated at reflux for 3 h and allowed to cool to ambient temperature. The toluene solution was washed with 5% aqueous sodium bicarbonate, dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. The residue was purified by chromatography on silica gel eluted with 10% ethyl acetate in hexane to give 13.1 g (64.2% yield) of the title compound; MS DCl--NH3 M/Z: 273 (M+NH4)+.

1. extractionThe aqueous mixture was extracted with three portions of diethyl ether
2. dry with materialThe ether extracts were dried over anhydrous magnesium sulfate
3. filtrationfiltered
4. concentrationconcentrated under reduced pressure
5. dissolutionThe residue was dissolved in 400 mL of toluene
6. addition20 g of p-toluenesulfonic acid was added
7. temperatureThe reaction mixture was heated
8. temperatureat reflux for 3 h
9. temperatureto cool to ambient temperature
10. washThe toluene solution was washed with 5% aqueous sodium bicarbonate
11. dry with materialdried over anhydrous magnesium sulfate
12. filtrationfiltered
13. concentrationconcentrated in vacuo
14. customThe residue was purified by chromatography on silica gel
15. washeluted with 10% ethyl acetate in hexane