Reacción #323720

Ecuación de reacción

L-aspartic acid

4-nitrophenyl isocyanate

→

yellow solid

Rendimiento 79.4%

N-(4-nitrophenylcarbamoyl)-L-aspartic acid

Rendimiento 79.4%

Disolventes

water

sodium hydroxide

sodium hydroxide

benzene

Condiciones de reacción

Tratamiento posterior

1. 1
   Otroa pH close to 10
2. 2
   Otrois obtained
3. 3
   Temperaturawhilst maintaining the pH at around 10
4. 4
   OtroThe weak precipitate formed
5. 5
   Filtraciónis eliminated by filtration
6. 6
   Lavadothe filtrate is washed with 3×50 cm3 of ethyl ether
7. 7
   Extracciónextracted with ethyl acetate, which
8. 8
   Otroto obtain
9. 9
   Secadoafter drying over anhydrous sodium sulfate

Procedimiento

4.56 g (0.0568 mol) of L-aspartic acid are dissolved in water by addition of sodium hydroxide until a pH close to 10 is obtained. A solution of 10 g (0.0568 mol) of 4-nitrophenyl isocyanate in 50 cm3 of benzene is then added at room temperature. The solution is stirred vigorously for two hours whilst maintaining the pH at around 10 by successive addition of a concentrated sodium hydroxide solution. The weak precipitate formed is eliminated by filtration and the filtrate is washed with 3×50 cm3 of ethyl ether. The aqueous phase is then acidified and extracted with ethyl acetate, which makes it possible to obtain, after drying over anhydrous sodium sulfate and after concentration, 13.4 g (yield 76%) of a yellow solid of which the melting point is 118°-120° C.

Fuente