Reaktion #81298

Reaktionsgleichung

ammonium chloride

methylmagnesium iodide

2-butyl-1-tritylimidazole-4,5-dicarbonitrile

diethyl ether

→

title compound

4-Acetyl-2-butyl-5-cyano-1-tritylimidazole

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooling, to the mixture
2. 2
   SonstigeThe tetrahydofuran layer was separated
3. 3
   Waschenwashed with a saturated aqueous solution of sodium chloride
4. 4
   Einengenconcentrated by evaporation under reduced pressure
5. 5
   Sonstigeto give a concentrate
6. 6
   ExtraktionThe aqueous layer was once again extracted with a small amount of ethyl acetate
7. 7
   WaschenThe extract was washed with a saturated aqueous solution of sodium chloride
8. 8
   Sonstigedried
9. 9
   Einengenconcentrated by evaporation under reduced pressure
10. 10
    ExtraktionThe resulting extract
11. 11
    Sonstigethe resulting crude product was purified by column chromatography through silica gel
12. 12
    workup.ADDITIONby volume mixture of hexane and ethyl acetate as the eluent
13. 13
    Sonstigethe product was crystallized from a mixture of ethyl acetate and hexane

Vorschrift

11.1 ml of a 2M solution of methylmagnesium iodide in diethyl ether was slowly added dropwise at room temperature, in an atmosphere of nitrogen, to a solution of 4.5 g of 2-butyl-1-tritylimidazole-4,5-dicarbonitrile [prepared as described in step (i) above] in 45 ml of tetrahydrofuran, and the resulting mixture was stirred at room temperature for 3 hours. At the end of this time, a saturated aqueous solution of ammonium chloride was added dropwise, whilst ice-cooling, to the mixture. The tetrahydofuran layer was separated, washed with a saturated aqueous solution of sodium chloride and concentrated by evaporation under reduced pressure to give a concentrate. The aqueous layer was once again extracted with a small amount of ethyl acetate. The extract was washed with a saturated aqueous solution of sodium chloride, dried and concentrated by evaporation under reduced pressure. The resulting extract was combined with the above concentrate, and the resulting crude product was purified by column chromatography through silica gel, using a 3:1 by volume mixture of hexane and ethyl acetate as the eluent, and the product was crystallized from a mixture of ethyl acetate and hexane, to give 1.46 g of the title compound, melting at 159°-160° C. (with decomposition).

Quelle