反应详情

Methyl 2-(2,6-difluorobenzyl)isonicotinate (5.031 g, 19.11 mmol) was dissolved in acetic acid (49 mL) and platinum(IV) oxide (0.217 g, 0.96 mmol) was added. The mixture was hydrogenated in a Büchi hydrogenator at room temperature and 5 bar for 5 h. More platinum(IV) oxide (0.108 g, 0.48 mmol) was added and hydrogenation was continued for 1 h. Additional platinum(IV) oxide (0.108 g, 0.48 mmol) was added and the mixture was again hydrogenated for 1.5 h. More platinum(IV) oxide (0.108 g, 0.48 mmol) was added. After a total of 8.5 h the reaction mixture was filtered through celite and the catalyst was washed with MeOH. The eluate was concentrated and DCM and 1 M K2CO3 were added. The phases were separated and the organic phase was washed with brine before it was dried and concentrated to yield methyl 2-(2,6-difluorobenzyl)piperidine-4-carboxylate (5.01 g, 97%). MS m/z 270 (M+H)+

1. customwas hydrogenated in a Büchi hydrogenator at room temperature
2. waithydrogenation was continued for 1 h
3. waitthe mixture was again hydrogenated for 1.5 h
4. filtrationAfter a total of 8.5 h the reaction mixture was filtered through celite
5. washthe catalyst was washed with MeOH
6. concentrationThe eluate was concentrated
7. additionDCM and 1 M K2CO3 were added
8. customThe phases were separated
9. washthe organic phase was washed with brine before it
10. customwas dried
11. concentrationconcentrated