反应详情

To a solution of 0.58 g of tert-butyl 1-(2-hydroxyethyl)piperidin-4-ylcarbamate obtained in step 1 in 10 ml of ethanol was added 1 ml of conc. HCl, followed by stirring for 2 hrs under reflux. The reaction mixture was cooled to room temperature, and concentrated in a reduced pressure to remove solvent. The residue was added with 10 ml of distilled water, neutralized with saturated sodium hydrogen carbonate aqueous solution, and extracted twice with 10 ml of methylene chloride. After being dried over a desiccant, the fraction was concentrated in a reduced pressure to afford 0.33 g of the title compound (Yield: 95%). 1H NMR (CDCl3) δ 3.68 (s, 2H), 3.60 (t, 2H), 2.86 (d, 2H), 2.69 (m, 1H), 2.53 (t, 2H), 2.11 (t, 2H), 1.82 (d, 2H), 1.42 (t, 2H) ppm.

1. temperatureunder reflux
2. concentrationconcentrated in a reduced pressure
3. customto remove solvent
4. additionThe residue was added with 10 ml of distilled water
5. extractionextracted twice with 10 ml of methylene chloride
6. customAfter being dried over a desiccant, the fraction
7. concentrationwas concentrated in a reduced pressure