反应详情

0.15 g of E-2-formylamino-4-phenyl-5-diethylphosphono-3-pentenoic acid methyl ester are dissolved in 10 ml of 4.5N hydrochloric acid and heated at 75° for 192 hours. After concentration in vacuo, the foamy 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 recrystallised from water/acetone (1:2). E-2-amino-4-phenyl-5-phosphono-3-pentenoic acid is thus obtained inthe form of colourless needles, m.p. 230°-233°.

1. temperatureheated at 75° for 192 hours
2. concentrationAfter concentration in vacuo
3. dissolutionthe foamy 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. customrecrystallised from water/acetone (1:2)