反应详情

温度

-78 °C

The 4-(4-benzyloxycarbonylaminopiperidin-1-yl)-benzoic acid ethyl ester (13.6 g, 35.6 mmol) obtained in Example 7 (2) was dissolved in dichloromethane (150 ml), and a diisobutylaluminum hydride-hexane solution (91 ml, 89.0 mmol) was added thereto, followed by stirring at −78° C. for 1 hour. Methanol was added to the reaction mixture, and then saturated sodium chloride was added thereto, followed by stirring. After the insoluble material was filtered with Celite, the solvent was evaporated from the filtrate under reduced pressure. The obtained residue was dissolved in dichloroethane (180 ml), and manganese dioxide (38.0 g) was added thereto, followed by stirring at 60° C. for 21 hours. After the insoluble material was filtered with Celite, the solvent was evaporated from the filtrate under reduced pressure, thereby obtaining 4-(4-benzyloxycarbonylaminopiperidin-1-yl)-benzaldehyde (7.0 g, 58%) as a white solid.

1. stirringby stirring
2. filtrationAfter the insoluble material was filtered with Celite
3. customthe solvent was evaporated from the filtrate under reduced pressure
4. dissolutionThe obtained residue was dissolved in dichloroethane (180 ml)
5. additionmanganese dioxide (38.0 g) was added
6. stirringby stirring at 60° C. for 21 hours
7. filtrationAfter the insoluble material was filtered with Celite
8. customthe solvent was evaporated from the filtrate under reduced pressure