反应详情

A solution of 1-(tert-butoxycarbonyl)-4-(2-hydroxyethyl)piperidine (328 mg, 1.43 mmol) in anhydrous THF (10 mL) was cooled to 0° C., and NaH (60% dispersion in oil, 69 mg, 1.71 mmol, 1.2 equiv.) was added all at once. Alkoxide formation was effected by stirring at room temperature for 2 h under N2, then 4-methylbenzyl bromide (317 mg, 1.71 mmol, 1.2 equiv.) was added. The mixture was stirred at room temperature overnight. Saturated aqueous NH4Cl solution was added, and the product was extracted into EtOAc. The organic layer was dried over Na2SO4 and concentrated. The residue was purified by CC (SiO2, EtOAc/hexane 1:4) to afford 1-(tert-butoxycarbonyl)-4-[2-(4-methylbenzyloxy)ethyl]piperidine (470 mg, 99%) after evaporation. 1H NMR (CDCl3, 400 MHz) δ 7.21 (d, 2H, J=8.0 Hz), 7.14 (d, 2H, J=8.0 Hz), 4.45 (s, 2H), 4.04 (d, 2H, J=13.6 Hz), 3.48 (t, 2H, J=6.4 Hz), 2.66 (t, 2H, J=13.6 Hz), 2.32 (s, 3H), 1.60 (m, 2H), 1.54 (m, 3H), 1.44 (s, 9H), 1.10(m, 2H).

1. stirringThe mixture was stirred at room temperature overnight
2. extractionthe product was extracted into EtOAc
3. dry with materialThe organic layer was dried over Na2SO4
4. concentrationconcentrated
5. customThe residue was purified by CC (SiO2, EtOAc/hexane 1:4)