Réaction #2045022

Équation de réaction

2-(4-Isocyanato-phenoxy)-propionic acid methyl ester

ethylene glycol

→

33

Rendement 50.8%

2-[4-(2-Hydroxy-ethoxycarbonylamino)-phenoxy]-propionic acid methyl ester

Rendement 50.8%

Solvants

Water

Conditions de réaction

Traitement

1. 1
   Autrerose to 58° C
2. 2
   Températureto cool
3. 3
   Extractioncrude 33 was extracted into chloroform
4. 4
   Lavagewashed with water (2×50 ml)
5. 5
   Séchagedried over sodium sulphate
6. 6
   workup.DISTILLATIONdistilled
7. 7
   AutreCrude 33 was purified by column chromatography on silica gel

Mode opératoire

2-(4-Isocyanato-phenoxy)-propionic acid methyl ester 32 (20 g, 90.49 mmol) was added to ethylene glycol (40 ml) at room temperature. The reaction was exothermic and the temperature rose to 58° C. The mixture was allowed to cool and later stirred at room temperature for 16 hours. Water (150 ml) was added and crude 33 was extracted into chloroform, washed with water (2×50 ml), dried over sodium sulphate and distilled. Crude 33 was purified by column chromatography on silica gel using chloroform as eluant to get pure 33 (13 gr, 50.76%) as a syrup which crystallized in 48 hours as a white powder. M.p: 90.5-92.8° C.

Source