反応 #2045038

反応方程式

2-(4-Aminophenoxy)propionic acid-2-[2-(4-aminophenoxy)propionyloxy]ethyl ester

dioxane

triphosgene

dioxane

→

51

収率 66.5%

2-(4-Isocyanatophenoxy)propionic acid-2-[2-(4-isocyanatophenoxy)propionyloxy]ethyl ester

収率 66.5%

反応条件

後処理

1. 1
   温度and cooled below 20° C
2. 2
   温度maintained for 2½ hours
3. 3
   workup.DISTILLATIONThe condenser was then arranged for distillation and solvent
4. 4
   その他removed by distillation at atmospheric pressure until the volume of reaction mixture
5. 5
   workup.ADDITIONFresh dry dioxane (50 ml) was added
6. 6
   workup.DISTILLATIONthe solvents were distilled off under vacuum
7. 7
   その他The residue was re-evaporated two times from dry dioxane

実験手順

2-(4-Aminophenoxy)propionic acid-2-[2-(4-aminophenoxy)propionyloxy]ethyl ester 50 (5.3 g, 13.6 mmol) was dissolved in dry dioxane (80 ml) under nitrogen atm. and cooled below 20° C. A solution of triphosgene (7 g, 23.6 mmol) in dry dioxane (20 ml) was added dropwise. The mixture was heated slowly to 75-80° C. and maintained for 2½ hours. The condenser was then arranged for distillation and solvent removed by distillation at atmospheric pressure until the volume of reaction mixture was reduced to approximately one third. Fresh dry dioxane (50 ml) was added and the solvents were distilled off under vacuum. The residue was re-evaporated two times from dry dioxane to give pure 51 (4 g, 66.5%) as a light brown liquid.

出典