Reaktion #587082

Reaktionsgleichung

1-benzyl-1H-imidazole

triethylamine

ethyl chloroformate

→

Ethyl 1-benzyl-1H-imidazole-2-carboxylate

Lösungsmittel

acetonitrile

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturAfter warming to 15 to 20° C.
2. 2
   workup.STIRRINGthe reaction mixture is stirred for 18 h
3. 3
   Einengenconcentrated in vacuo
4. 4
   workup.ADDITIONThe residue is mixed with water, saturated sodium chloride solution and saturated sodium bicarbonate solution
5. 5
   Extraktionextracted three times with ethyl acetate
6. 6
   WaschenThe combined organic phases are washed with saturated sodium chloride solution
7. 7
   Trocknenafter drying with magnesium sulphate
8. 8
   Sonstigeevaporated in vacuo
9. 9
   workup.DISTILLATIONThe residue is fractionally distilled under high vacuum (boiling point=173 to 181° C., pressure=1.7 to 1.2 mbar)

Vorschrift

148 g (936 mmol) of 1-benzyl-1H-imidazole are suspended in 480 ml of acetonitrile and, at −20° C., 120 ml (87.1 g; 860 mmol) of triethylamine are added. Then, over the course of 15 minutes, 211.2 ml (239 g; 2208 mmol) of ethyl chloroformate are added dropwise. The reaction mixture is stirred at −20° C. for 10 minutes. After warming to 15 to 20° C., the reaction mixture is stirred for 18 h and then concentrated in vacuo. The residue is mixed with water, saturated sodium chloride solution and saturated sodium bicarbonate solution and extracted three times with ethyl acetate. The combined organic phases are washed with saturated sodium chloride solution and, after drying with magnesium sulphate, evaporated in vacuo. The residue is fractionally distilled under high vacuum (boiling point=173 to 181° C., pressure=1.7 to 1.2 mbar).

Quelle