反应详情

温度

-50 °C

Lithium bis(trimethylsilyl)amide (LiHMDS) in THF (1.0 M, 45 mL) was added to a solution of 1-benzyl 4-methyl piperidine-1,4-dicarboxylate (10.0 g, 0.0360 mol) at −78° C. The reaction mixture was slowly warmed to −50° C. and kept at this temperature for 10 min, and then re-cooled to −78° C. 3-Iodo-1-propene (4.95 mL, 0.0541 mol) was added slowly. After the addition, the mixture was allowed to warm slowly to room temperature and kept at room temperature for 3 hours. The mixture was carefully quenched (the pH was adjusted to 4) with 1N HCl solution, and ethyl acetate (200 mL) was added. The organic layer was separated and washed with water, NaHCO3 (7.5%), brine, dried over MgSO4, and filtered. The filtrate was concentrated. The residue was purified by flash chromatography with 20% ethyl acetate in hexane to give 1-benzyl 4-methyl 4-allylpiperidine-1,4-dicarboxylate (10.4 g, 90.9%).

1. temperaturere-cooled to −78° C
2. additionAfter the addition
3. temperatureto warm slowly to room temperature
4. waitkept at room temperature for 3 hours
5. customThe mixture was carefully quenched (the pH
6. additionwas added
7. customThe organic layer was separated
8. washwashed with water, NaHCO3 (7.5%), brine
9. dry with materialdried over MgSO4
10. filtrationfiltered
11. concentrationThe filtrate was concentrated
12. customThe residue was purified by flash chromatography with 20% ethyl acetate in hexane