反应详情

A mixed solution of 18 ml conc. sulfuric acid and 1.8 ml water was cooled to 0° C., and 5 g of 1-benzyl-4-hydroxy-4-piperidinecarbonitrile hydrochloride was added thereto little by little. A mixed solution of 25 ml conc. sulfuric acid and 2.5 ml water was added thereto, and stirred at room temperature for 2 hr. It was left overnight in a freezer. The reaction solution was poured onto ice, and 47 g of sodium hydroxide was added thereto little by little. It was extracted 3 times with a mixed solvent of tetrahydrofuran and ethyl acetate (1:1). The extract was washed with brine, dried over anhydrous magnesium sulfate, and then filtered. The filtrate was evaporated and subjected to silica gel column chromatography to give 3.19 g of 1-benzyl-4-hydroxy-4-piperidine carboxamide.

1. waitIt was left overnight in a freezer
2. additionwas added
3. extractionIt was extracted 3 times with a mixed solvent of tetrahydrofuran and ethyl acetate (1:1)
4. washThe extract was washed with brine
5. dry with materialdried over anhydrous magnesium sulfate
6. filtrationfiltered
7. customThe filtrate was evaporated