反应详情

Formylhydrazine (120 mg) was added to a solution of ethyl (2S)-1-[(4-fluorophenyl)sulfonyl]-2-piperidinecarboximidate (295 mg) [see Preparation 41] in toluene (5 ml) and 1,4-dioxane (5 ml). The reaction mixture was stirred at reflux for 26 hours after which time the solvent was removed under reduced pressure. The residue was diluted with ethyl acetate and washed with water. The organic layer was separated, dried over magnesium sulphate and the solvent removed under reduced pressure. The crude product was purified by column chromatography on silica gel eluting with a solvent gradient of 100:0 changing to 0:100 (in 10% increments), by volume, hexane:ethyl acetate to afford (2S)-1-[(4-fluorophenyl)sulfonyl]-2-(1H-1,2,4-triazol-3-yl)piperidine (95 mg) as an off-white foam.

1. temperatureat reflux for 26 hours after which time the solvent
2. customwas removed under reduced pressure
3. additionThe residue was diluted with ethyl acetate
4. washwashed with water
5. customThe organic layer was separated
6. dry with materialdried over magnesium sulphate
7. customthe solvent removed under reduced pressure
8. customThe crude product was purified by column chromatography on silica gel eluting with a solvent gradient of 100:0 changing to 0:100 (in 10% increments), by volume, hexane