反应详情

Thionyl chloride (10.5 ml) was added to 1-benzyl-4-piperidinecarboxylic acid (4.85 g, 22.1 mmol), and the resulting mixture was refluxed for 2 hours. The reaction solution was distilled under reduced pressure to remove the solvent. To a solution of the resulting residue in methylene chloride (65 ml) were added 5-aminoindazole (4.41 g, 33.2 mmol), triethylamine (1.8 ml), pyridine (30 ml) and a catalytic amount of 4-dimethylaminopyridine at 0° C., and then stirred at room temperature for 3 hours. Then, the reaction solution was poured into a 1N-aqueous sodium hydroxide solution and extracted with chloroform. The organic layer was washed with a saturated aqueous sodium chloride solution and then dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by a silica gel column chromatography (eluent: chloroform/methanol=20/1) to obtain 1-benzyl-N-(1H-indazol-5-yl)-4-piperidinecarboxamide (2.2 g, 30%).

1. temperaturethe resulting mixture was refluxed for 2 hours
2. distillationThe reaction solution was distilled under reduced pressure
3. customto remove the solvent
4. extractionextracted with chloroform
5. washThe organic layer was washed with a saturated aqueous sodium chloride solution
6. dry with materialdried over anhydrous sodium sulfate
7. distillationThe solvent was distilled off under reduced pressure
8. customthe resulting residue was purified by a silica gel column chromatography (eluent: chloroform/methanol=20/1)