反应详情

4-(3-(1-Methylethoxy)phenyl)-1-piperidine-carboxylic acid phenyl ester (Preparation 46, 1.7 g, 5.01 mmol) was heated under reflux in 47% aqueous hydrobromic acid:glacial acetic acid (1:1, 20 ml) for 16 h. The solution was allowed to cool to room temperature and water (10 ml) was added. The solution was extracted with methyl tert-butyl ether (3×10 ml) to remove phenol as a by-product. The pH was adjusted to 10.3-10.5 with 15% w:v aqueous sodium hydroxide solution and the reaction mixture was left at room temperature for 2 h to precipitate the product. After cooling to 0° C. the precipitate was filtered and washed with cold water (5 ml) to give the title compound as a solid (380 mg, 43%).

1. extractionThe solution was extracted with methyl tert-butyl ether (3×10 ml)
2. customto remove phenol as a by-product
3. customto precipitate the product
4. temperatureAfter cooling to 0° C. the precipitate
5. filtrationwas filtered
6. washwashed with cold water (5 ml)