反应详情

In dichloromethane (20 ml) was dissolved N-tert-butoxycarbonyl-4-(1-hydroxyethyl)piperidine (0.92 g). After addition of carbon tetrabromide, (1.62 g), triphenylphosphine (1.58 g) was slowly added under ice-cooling. The mixture was stirred at room temperature for 2 hours, at the end of which time the dichloromethane was distilled off. The residue was diluted with ethyl acetate and an aqueous solution of NaHCO3 and the insoluble matter was filtered off. The filtrate was extracted with ethyl acetate, washed with aqueous NaCl solution, dried over MgSO4, and concentrated. The residue was purified by silica gel column chromatography (hexane: ethyl acetate =8:1) to provide the title compound as colorless oil (1.34 g). 1H-NMR (CDCl3) δ: 1.0-1.3(3H,m), 1.4;5(9H,s), 1.6-1.9(4H,m), 2.6-2.8(2H,brm), 3.45(2H,t,J=6.8Hz), 4.0-4.2(2H,brm).

1. additionwas slowly added under ice-
2. temperaturecooling
3. distillationwas distilled off
4. additionThe residue was diluted with ethyl acetate
5. filtrationan aqueous solution of NaHCO3 and the insoluble matter was filtered off
6. extractionThe filtrate was extracted with ethyl acetate
7. washwashed with aqueous NaCl solution
8. dry with materialdried over MgSO4
9. concentrationconcentrated
10. customThe residue was purified by silica gel column chromatography (hexane: ethyl acetate =8:1)