反应详情

Dicyclohexylcarbodiimide (1.03 g.) is added to a solution of 3-acetylthio-2-carbamoylmethylpropanoic acid (1.02 g.) in pyridine (18 ml.). After five hours stirring at room temperature, the precipitate is filtered off and the filtrate is concentrated in dryness, the residue is dissolved in ethyl acetate and extracted with saturated aqueous bicarbonate. The aqueous phase is acidified and extracted with ethyl acetate. This organic layer is dried and concentrated to dryness. The residue, 3-acetylthio-2-cyanomethylpropanoic acid is crystallized from ether-hexane, m.p. 110°-112°.

1. filtrationthe precipitate is filtered off
2. concentrationthe filtrate is concentrated in dryness
3. dissolutionthe residue is dissolved in ethyl acetate
4. extractionextracted with saturated aqueous bicarbonate
5. extractionextracted with ethyl acetate
6. customThis organic layer is dried
7. concentrationconcentrated to dryness
8. customThe residue, 3-acetylthio-2-cyanomethylpropanoic acid is crystallized from ether-hexane, m.p. 110°-112°