反应详情

To a boiling solution of 23 g. (0.067 mol.) of N-t-butoxycarbonyl-2-(2,4-dihydroxyphenyl)glycine n-butyl ester in 300 ml. of methanol was slowly added a solution of 23 g. of sodium bicarbonate in 300 ml. of water. During addition, the reaction mixture was kept under a nitrogen atmosphere and the methanol was allowed to distill from the mixture. When all the methanol had been distilled the mixture was cooled, adjusted to pH 7.0 with phosphoric acid and extracted with ethyl acetate. The aqueous phase was acidified to pH 4.0 and again extracted with ethyl acetate. The extract was dried (Na2SO4) and concentrated in vacuo to give the title compound.

1. additionDuring addition
2. distillationto distill from the mixture
3. distillationWhen all the methanol had been distilled the mixture
4. temperaturewas cooled
5. extractionextracted with ethyl acetate
6. extractionagain extracted with ethyl acetate
7. dry with materialThe extract was dried (Na2SO4)
8. concentrationconcentrated in vacuo