反应详情

温度

10 °C

Powdered KOH (0.92 g, 16.44 mmol) was added in portions to the stirred solution of methylamine hydrochloride (1.11 g, 16.44 mmol) in methanol (20 ml) at 0-5° C. and 1-carbethoxy-3,5-dimethyl-4-piperidinone (2.2 g, 1.1 mmol),obtained by a procedure as described in Example 25 (Step-1), was added in portions to it. The resulting reaction mixture was stirred for 45 min at 10° C. and a solution of sodium cyanoboro-hydride (0.7 g, 1.1 mmol) in methanol (5 ml) was added dropwise to it. Cooling was removed and stirring was for 24 hr at 30° C. The reaction mixture was basified with 20% KOH solution, filtered (to remove insoluble impurities) and filtrate was concentrated to dryness. The obtained residue was dissolved in water and extracted with chloroform. Chloroform layer was extracted with 50% HCl and acid layer was basified with 20% KOH solution. The separated oil was extracted with chloroform, dried (Na2SO4) and concentrated to give a Mixtures A+B of 4-methylamino-1-carbethoxy-3,5-dimethylpiperidine. Yield 1.34 g (60%), C11H22N2O2, m/z 214 (M+1).

1. additionwas added in portions to it
2. customThe resulting reaction mixture
3. temperatureCooling
4. customwas removed
5. stirringstirring
6. waitwas for 24 hr at 30° C
7. filtrationfiltered
8. custom(to remove insoluble impurities) and filtrate
9. concentrationwas concentrated to dryness
10. dissolutionThe obtained residue was dissolved in water
11. extractionextracted with chloroform
12. extractionChloroform layer was extracted with 50% HCl and acid layer
13. extractionThe separated oil was extracted with chloroform
14. dry with materialdried (Na2SO4)
15. concentrationconcentrated