4,4'-Dichlorobenzophenone → alpha,alpha-Bis(p-chlorophenyl)-1-(methoxymethyl)imidazole-2-methanol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 11.2 g. (0.1 mol) of 1-(methoxymethyl)-imidazole and 13.9 g. (0.12 mol) of N,N,N',N'-tetramethylethylenediamine in 150 ml. of anhydrous tetrahydrofuran 51 ml. (0.12 mol) of n-butyllithium solution in hexane was added with stirring over a period of about one hour and at a temperature of -60° C. Stirring was continued for another 2 hours at -60° C. Cooling was discontinued and 25.1 g. (0.1 mol) of 4,4'-dichlorobenzophenone in 150 ml. of anhydrous tetrahydrofuran was added drop-wise. The mixture was stirred for 6 hours at room temperature and decomposed by addition of 15 ml. of water. Lithium hydroxide was removed by filtration and the filtrate was concentrated. A 2 N hydrochloric acid solution was added and the mixture was extracted with liberal amounts of diethyl ether. The acidic aqueous solution was made alkaline by addition of potassium carbonate and extracted with diethyl ether, toluene and ethyl acetate. The organic solvent solutions were combined, dried and concentrated. The solid was purified by crystallisation from toluene; its melting point was 145°-146° C.

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