反应详情

温度

0 °C

Ammonium acetate (20 g) was added to the stirred solution of 1-carbethoxy-3,5-dimethyl-4-piperidinone (4.5 g, 22.5 mmol) in methanol (200 ml) and stirred for 3 hr. The resulting mixture was cooled at 0° C. and sodium cyanoborohydride (1.4 g, 22.5 mmol) was added to it. Cooling was removed and stirring was for 3 hr at 35° C. The reaction mixture was concentrated, triturated with water, acidified with conc. HCl (pH 3˜4) and extracted with ethyl acetate to remove impurities. The aqueous layer was basified with 1 M sodium hydroxide solution (pH ˜10) and extracted with ethyl acetate. Ethyl acetate extract was dried (Na2SO4) and concentrated to give 4-amino-1-carbethoxy-3,5-dimethylpiperidine. The obtained 4-amino-1-carbethoxy-3,5-dimethylpiperidine was subjected to silica gel column chromatography. Elution with 5% methanol in chloroform furnished a solid, which was a mixture of stereoisomers, conformational analysis of which was not obtained.

1. temperatureCooling
2. customwas removed
3. stirringstirring
4. waitwas for 3 hr at 35° C
5. concentrationThe reaction mixture was concentrated
6. customtriturated with water
7. extractionextracted with ethyl acetate
8. customto remove impurities
9. extractionextracted with ethyl acetate
10. extractionEthyl acetate extract
11. dry with materialwas dried (Na2SO4)
12. concentrationconcentrated