反応 #531854

反応方程式

HCl

4-aminobutyric acid

DBU

cyclohexyl isocyanate

→

4-(3-Cyclohexyl-ureido)-butyric acid

収率 76.0%

溶媒

NaOH

反応条件

後処理

1. 1
   workup.ADDITIONThe mixture was strongly mixed at room temperature overnight
2. 2
   ろ過The formed white solid was collected by filtration
3. 3
   その他The mixture was purified by chromatography on a silica column (8×3 cm)
4. 4
   洗浄Elution with a mixture 50:50:1 of hexane
5. 5
   その他ethyl acetate:acetic acid gave the pure targeted product

実験手順

To a cold solution of 4-aminobutyric acid (2.16 g, 21 mmol) and catalytic amount of DBU in 22 mL of 1.0 N NaOH, 2.5 g (20 mmol) of cyclohexyl isocyanate were added in one time. The mixture was strongly mixed at room temperature overnight. The reaction was then acidified with concentrated HCl. The formed white solid was collected by filtration. The mixture was purified by chromatography on a silica column (8×3 cm). Elution with a mixture 50:50:1 of hexane:ethyl acetate:acetic acid gave the pure targeted product. The resulting white crystal (3.46 g; yield: 76%) had a mp of 153.0-154.0° C. [M+H]+ 281.18.

出典