Reaktion #349149

Reaktionsgleichung

phenyl lithium

N-benzylimidazole

4,4'-dichlorobenzophenone

sodium chloride

lithium

bromobenzene

→

1-Benzyl-α,α-bis(p-chlorophenyl)imidazole-2-methanol

Lösungsmittel

tetrahydrofuran

diethyl ether

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was heated for about one hour until a brightly red, homogenous solution
2. 2
   Sonstigewas obtained
3. 3
   Sonstigethe organic phase was separated off
4. 4
   Einengenconcentrated
5. 5
   workup.DISSOLUTIONThe residue was dissolved in a small amount of acetone
6. 6
   workup.ADDITIONThen some toluene was added
7. 7
   Sonstigethe precipitate formed
8. 8
   Filtrationwas filtered off
9. 9
   Sonstigecrystallised from a mixture of isopropyl alcohol and petroleum ether (boiling range 28°-40° C.)

Vorschrift

A solution of 17.4 g (0.11 mol) of N-benzylimidazole in 40 ml. of anhydrous tetrahydrofuran was added dropwise in the course of one hour, at -20° to -30° C. and under a nitrogen atmosphere, to a phenyl lithium solution, prepared from 1.67 g (0.24 gr. at.) of lithium and 18.8 g (0.12 mol) of bromobenzene in 80 ml. of anhydrous diethyl ether. The mixture was heated for about one hour until a brightly red, homogenous solution was obtained. Subsequently a solution of 25.1 g (0.1 mol) of 4,4'-dichlorobenzophenone in 60 ml. of anhydrous tetrahydrofuran was added in the course of one hour at a temperature between -25° and -15° C. The reaction mixture was stirred for 15 hours at room temperature, under the nitrogen atmosphere and it was then poured on 200 g of ice. The aqueous phase was saturated with sodium chloride and the organic phase was separated off and concentrated. The residue was dissolved in a small amount of acetone and the solution was acidified with 2 N hydrochloric acid. Then some toluene was added and the precipitate formed was filtered off. The product was thrice crystallised from a mixture of isopropyl alcohol and petroleum ether (boiling range 28°-40° C.). 1-Benzyl-α,α-bis(p-chlorophenyl)imidazole-2-methanol was obtained. Melting point 167°-168° C.

Quelle