反応 #725901

反応方程式

(4-Amino-phenoxy)-acetic acid methyl ester

triethylamine

triphosgene

→

28

収率 159.1%

(4-Isocyanato-phenoxy)-acetic acid methyl ester

収率 159.1%

溶媒

toluene

反応条件

後処理

1. 1
   温度Later the reaction mixture was heated to 75° C. over a period of one hour
2. 2
   温度maintained at this temperature for 26 hours
3. 3
   温度The reaction mixture was then cooled to room temperature
4. 4
   ろ過the solids were filtered off
5. 5
   workup.DISTILLATIONthe toluene was distilled off under vacuum
6. 6
   その他to get crude 28, which
7. 7
   workup.DISTILLATIONdistilled

実験手順

To a mixture of (4-Amino-phenoxy)-acetic acid methyl ester 15 (15 g, 82.87 mmol) and triethylamine (16.77 g, 165.73 mmol) in toluene (225 ml) under nitrogen atm. at 0° C. was added triphosgene (9 g, 30.33 mmol) in one lot. The reaction was exothermic and the temperature raised to 25° C. Later the reaction mixture was heated to 75° C. over a period of one hour and maintained at this temperature for 26 hours. The reaction mixture was then cooled to room temperature, the solids were filtered off, and the toluene was distilled off under vacuum to get crude 28, which was vacuum distilled to get pure 28 (10 g, 58.3%) as a white powder. M.p: 50-53° C.

出典