反应详情

Crude ethyl 3-methyl-2-(5-phenyl-1,3,4-oxadiazol-2-ylamino)butanoate (assumed 5 mmol) was dissolved in a mixture of THF (10 ml) and MeOH (2 ml) and then treated dropwise (exothermic) with aqueous 1 N NaOH (6 mL) solution. The reaction was stirred for 1 h, diluted with H2O (50 mL) and then extracted with Et2O (1×50 mL). The aqueous layer was acidified to pH 3 with aqueous 1N HCl solution and then extracted with EtOAc (3×35 mL). The EtOAc extracts were combined, washed with sat. aqueous NaCl solution, dried (MgSO4) and the solvent was removed in vacuo to give 3-methyl-2-(5-phenyl-1,3,4-oxadiazol-2-ylamino)butanoic acid in 50-75% yield over 3 steps in purity >90% as judged by LCMS. MS found: 262 (M+H).

1. extractionextracted with Et2O (1×50 mL)
2. extractionextracted with EtOAc (3×35 mL)
3. washwashed with sat. aqueous NaCl solution
4. dry with materialdried (MgSO4)
5. customthe solvent was removed in vacuo