反应详情

To 1.99 g (4.7 mmol) of (R)-α-cyano-3-phenoxybenzyl (R)-N-1-(1-naphthyl)ethylcarbamate in 20 ml of benzene is added 725 μl (525 mg, 5.2 mmol) of triethylamine. The solution, under nitrogen, is stirred while 505 μl (675 mg, 5.0 mmol) of trichlorosilane is added. The reaction is warmed to 50° for 2.5 hours, and is then poured into saturated ammonium chloride and ether. The organic fraction is washed again with saturated ammonium chloride and then with brine (3×), and is dried over sodium sulfate overnight in the freezer. Solvent is removed by rotoevaporation, and the residue is washed repeatedly with hexane to remove the isocyanate. The urea contamination is removed by dissolving the product in ether/hexane (~1:1), and the solvent is then removed. Purification by thin layer chromatography (tlc) on silica gel plates developed in 30% ethylacetate/hexane yields the product, which is then dissolved in trichloromethane. The solvent is removed, giving (R)-α-cyano-3-phenoxybenzyl alcohol, specific rotation [α]D =+15.2° (c=10 mg/ml in acetone).

1. additionis added
2. temperatureThe reaction is warmed to 50° for 2.5 hours
3. washThe organic fraction is washed again with saturated ammonium chloride
4. dry with materialwith brine (3×), and is dried over sodium sulfate overnight in the freezer
5. customSolvent is removed by rotoevaporation
6. washthe residue is washed repeatedly with hexane
7. customto remove the isocyanate
8. customThe urea contamination is removed
9. dissolutionby dissolving the product in ether/hexane (~1:1)
10. customthe solvent is then removed
11. customPurification by thin layer chromatography (tlc) on silica gel plates
12. customyields the product, which
13. customThe solvent is removed