Réaction #327988

Équation de réaction

hydrochloric acid

sodium thiocyanate

2-aminopropiophenone hydrochloride

ethanol

→

title compound

Rendement 45.0%

5-Ethyl-4-phenylimidazole

Rendement 45.0%

Conditions de réaction

Traitement

1. 1
   workup.DISTILLATIONThe solvent was distilled away
2. 2
   workup.ADDITIONacetic acid (20 mL) was then added to the residue
3. 3
   workup.STIRRINGThe obtained mixture was stirred at 100° C. for 3 hours
4. 4
   workup.ADDITIONThereafter, water was added to the reaction solution
5. 5
   Autrethe precipitated crude crystals
6. 6
   Filtrationwere collected by filtration
7. 7
   workup.ADDITIONRaney Ni was added to a solution of the
8. 8
   Autreobtained crude crystals in ethanol (40 mL)
9. 9
   workup.STIRRINGthe obtained mixture was then stirred at 70° C. for 2 hours
10. 10
    FiltrationThe reaction solution was filtered with celite
11. 11
    Concentrationthe filtrate was then concentrated
12. 12
    LavageThe residue was washed with acetonitrile

Mode opératoire

An aqueous solution (5 mL) of concentrated hydrochloric acid (0.6 mL) and sodium thiocyanate (1.62 g, 20.03 mmol) was added to a solution of 2-aminopropiophenone hydrochloride (2.00 g, 10.02 mmol) in ethanol (20 mL). The obtained mixture was stirred at 70° C. for 1 hour. The solvent was distilled away, and acetic acid (20 mL) was then added to the residue. The obtained mixture was stirred at 100° C. for 3 hours. Thereafter, water was added to the reaction solution, and the precipitated crude crystals were collected by filtration. Raney Ni was added to a solution of the obtained crude crystals in ethanol (40 mL), and the obtained mixture was then stirred at 70° C. for 2 hours. The reaction solution was filtered with celite, and the filtrate was then concentrated. The residue was washed with acetonitrile, so as to obtain the title compound (0.88 g, yield in two steps: 45%).

Source