反应详情

Dissolve 2-amino-3-(2-vinyl-phenyl)-propionic acid (3.40 g) in water (75 mL) and add sodium carbonate (1.97 g, 18.6 mmol) and N-carbethoxyphthalimide (2.81 g, 12.8 mmol). Stir for 2.5 hours, wash with methylene chloride (200 mL), acidify to pH 1 with cold concentrated hydrochloric acid and extract with ethyl acetate (3×200 mL), dry (Na2SO4), evaporate the solvent in vacuo and purify by silica gel chromatography (1:1:2% hexane/ethyl acetate/acetic acid) followed by recrystallization (isopropranol) to give the title compound as a pale yellow solid (2.47 g).

1. washwash with methylene chloride (200 mL)
2. extractionextract with ethyl acetate (3×200 mL)
3. dry with materialdry (Na2SO4)
4. customevaporate the solvent in vacuo
5. custompurify by silica gel chromatography (1:1:2% hexane/ethyl acetate/acetic acid)
6. customfollowed by recrystallization (isopropranol)