反应详情

(2S)-2-Piperidinecarboxylic acid L-tartrate (42 g) [see Preparation 1] was dissolved in 10% w/w aqueous sodium hydroxide solution (600 ml) and 1H-benzo[d]imidazole-2-sulfonyl chloride (39 g) [see Preparation 8] was added. The reaction mixture was stirred at room temperature for 56 hours after which time the product was extracted with ethyl acetate. The organic layer was separated, 2N aqueous hydrochloric acid solution added and the acidic aqueous layer extracted twice with ethyl acetate. The combined organic layers were dried over magnesium sulphate and the solvent removed under reduced pressure. The crude product was purified by column chromatography on silica gel eluting with 95:5:0.5, by volume, dichloromethane:methanol:glacial acetic acid to afford 1-(1H-benzo[d]imidazol-2-ylsulfonyl)-2-piperidinecarboxylic acid (17.5 g).

1. additionwas added
2. extractionwas extracted with ethyl acetate
3. customThe organic layer was separated
4. addition2N aqueous hydrochloric acid solution added
5. extractionthe acidic aqueous layer extracted twice with ethyl acetate
6. dry with materialThe combined organic layers were dried over magnesium sulphate
7. customthe solvent removed under reduced pressure
8. customThe crude product was purified by column chromatography on silica gel eluting with 95:5:0.5, by volume, dichloromethane