Reaktion #170965

Reaktionsgleichung

2-(4-aminophenoxy)-propionic acid methyl ester

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

triethylamine

triphosgene

→

11

Ausbeute 143.8%

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

Ausbeute 143.8%

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturmaintained at this tempera-ture for 26 hours
2. 2
   TemperaturThe reaction mixture was cooled to room temperature
3. 3
   Filtrationthe solids filtered off
4. 4
   workup.DISTILLATIONthe toluene was distilled off under vacuum
5. 5
   Sonstigeto get crude 11, which
6. 6
   workup.DISTILLATIONdistilled

Vorschrift

To a mixture of 2-(4-aminophenoxy)-propionic acid methyl ester 10 (15 g, 76.9 mmol) and triethylamine (15.6 g, 154.16 mmol) in toluene (210 ml) under nitrogen atmosphere was added triphosgene (8.4 g, 28.3 mmol) in one lot. Later the reaction mixture was heated to 75° C. over a period of one hour and maintained at this tempera-ture for 26 hours. The reaction mixture was cooled to room temperature, the solids filtered off, and the toluene was distilled off under vacuum to get crude 11, which was vacuum distilled to get pure 11 (9 grams, 52.9%) as a light yellow syrup.

Quelle