反应详情

0.44 g of E-2-formylamino-4-benzyl-5-diethylphosphono-3-pentenoic acid ethyl ester are dissolved in ml of 4.5 N hydrochloric acid and heated at 85° for hours. After concentration in vacuo, the residue is dissolved in a small amount of ethanol and 1 ml of ethanol/propylene oxide (1:1) is added dropwise thereto. The resulting white precipitate is filtered off and, after recrystallisation from water, E-2-amino-4-benzyl-5-phosphono-3-pentenoic acid is obtained in the form of colourless needles, m.p. 196°-198°.

1. temperatureheated at 85° for hours
2. concentrationAfter concentration in vacuo
3. dissolutionthe residue is dissolved in a small amount of ethanol and 1 ml of ethanol/propylene oxide (1:1)
4. additionis added dropwise
5. filtrationThe resulting white precipitate is filtered off
6. customafter recrystallisation from water