反应详情

6.25 g of 4,5-bis(4-methoxyphenyl)-2-mercaptoimidazole is dissolved in 150 ml of absolute dimethylformamide and combined with 0.60 g of sodium hydride (80% in oil). After the evolution of hydrogen has ceased, the solution is cooled to 0°, combined with a pinch of powdered copper, and then a diazonium salt solution, cooled to 0° and prepared from 3.26 g of 4-trifluoromethylaniline (99%), 1.38 g of sodium nitrite, as well as 10 ml of 6N hydrochloric acid, is added dropwise to the reaction mixture. The latter is agitated for 30 minutes at 0° and then allowed to warm up to room temperature. The solution is then concentrated under vacuum, the residue is distributed between water and ethyl acetate; the organic solution is dried over sodium sulfate and concentrated to dryness under vacuum. The residue is chromatographed on 500 g of aluminum oxide, neutral, activity stage II, with hexane/ethyl acetate 3:2 as the eluting agent. Elution yields 3.39 g of 4,5-bis(4-methoxyphenyl)-2-(4-trifluoromethylphenylthio)imidazole, mp 179°-181°.

1. temperaturethe solution is cooled to 0°
2. concentrationThe solution is then concentrated under vacuum
3. dry with materialthe organic solution is dried over sodium sulfate
4. concentrationconcentrated to dryness under vacuum
5. customThe residue is chromatographed on 500 g of aluminum oxide
6. washElution