反应详情

A solution of phenylchloroformate (0.045 ml, 0.36 mmol), triethylamine (0.085 ml), 4-dimethylaminopyridine (catalytic) and trans-4(2,4-bis{[tert-butyl(dimethyl)silyl]oxy}phenyl) cyclohexylamine (0.043 g) in dichloroethane (11 ml) was stirred at room temperature for 60 hr. The mixture was partitioned between saturated aqueous sodium carbonate (15 ml) and dichloromethane (15 ml). The aqueous phase was extracted with dichloromethane (2×15 ml) and the combined organic extracts washed with brine (20 ml), dried over magnesium sulfate, filtered and concentrated in vacuo. Purification via flash chromatography (SiO2, ethyl acetate/petroleum ether) afforded a colourless gum. This was dissolved in dichloromethane (15 ml) and warmed with a mixture of water (7.5 ml) and trifluoroacetic acid (7.5 ml) at 80° C. for 17 hr. On cooling, toluene (25 ml) was added and the solution concentrated in vacuo. Methanol (25 ml) was added and the solution again concentrated in vacuo. Purification via flash chromatography (SiO2, ethyl acetate/petroleum ether) afforded the title compound (0.013 g, 13%) as a colourless solid. δH (CD3OD) 1.44-1.63 (4H, m), 1.96 (2H, m), 2.13 (2H, m), 2.86 (1H, m), 3.55 (1H, m), 6.30 (2H, m), 6.92 (1H, d), 7.12 (2H, m), 7.22 (1H, m) and 7.40 (2H, m); m/s(ES+) 328.26 (M+H)+.

1. customThe mixture was partitioned between saturated aqueous sodium carbonate (15 ml) and dichloromethane (15 ml)
2. extractionThe aqueous phase was extracted with dichloromethane (2×15 ml)
3. washthe combined organic extracts washed with brine (20 ml)
4. dry with materialdried over magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customPurification via flash chromatography (SiO2, ethyl acetate/petroleum ether)
8. customafforded a colourless gum
9. temperatureOn cooling
10. concentrationthe solution concentrated in vacuo
11. additionMethanol (25 ml) was added
12. concentrationthe solution again concentrated in vacuo
13. customPurification via flash chromatography (SiO2, ethyl acetate/petroleum ether)