反应详情

300 mg of 1-(triphenylmethyl)-4-(3-hydroxypropyl)-1H-imidazole (0.81 mmol) are dissolved in 8 ml of freshly distilled THF. 277 mg of triphenylphosphine (1.06 mmol) and 145 mg m-trifluoromethylphenol are added thereto, and the resulting mixture is cooled and stirred for 5 minutes under nitrogen. Diethyl azodicarboxylate (184 mg; 1.06 mmol), dissolved in freshly distilled THF (4 ml), is added gradually to the reaction mixture and while stirring continuously at room temperature for 12 hours. After removal of the solvent in vacuo, column chromatography (SiO2; first eluent: petroleum spirit; second eluent: petroleum spirit/diethyl ether (50:50)) performed on the crude reaction mixture gives a white powder which is reduced in petroleum ether to give an oil of 1-(triphenylmethyl)-4-[3-(trifluoromethylphenoxy)-propyl]-1H-imidazole. The latter (210 mg; 0.41 mmol) is heated at 70° C. for 3 hours in THF (5 ml) and 2N HCl (12 ml). The THF is removed under reduced pressure and Ph3COH is extracted with diethyl ether. The aqueous phase is neutralized with potassium carbonate and the product is extracted into diethyl ether or chloroform. This solution is dried and evaporated, giving an oil which is dissolved in 2-propanol. Oxalic acid (1.5 equivalents) is added and the abovementioned product (on addition of diethyl ether) in the form of the oxalate, m.p.: 204-208° C.

1. temperaturethe resulting mixture is cooled
2. additionis added gradually to the reaction mixture
3. stirringwhile stirring continuously at room temperature for 12 hours
4. customAfter removal of the solvent in vacuo, column chromatography (SiO2; first eluent: petroleum spirit; second eluent: petroleum spirit/diethyl ether (50:50))
5. customreaction mixture
6. customgives a white powder which