反应详情

温度

-70 °C

43 ml of a 1 M solution of diisobutyl-aluminium hydride in tetrahydrofuran are added dropwise to a solution of 13.5 g of dimethyl 2-bromo-1-(2-butyn-1-yl)-1H-imidazole-4,5-dicarboxylate in 220 ml of tetrahydrofuran under an argon atmosphere at −70° C. within 20 minutes. The mixture is stirred for a further four hours at −70° C., then 20 ml of a mixture of 1 M hydrochloric acid and tetrahydrofuran are added dropwise. After heating to ambient temperature approx. 200 ml of water are added and the mixture is extracted three times with 70 ml of ethyl acetate. The combined extracts are dried and evaporated down. The crude product thus obtained is purified by column chromatography through silica gel with petroleum ether/ethyl acetate (80:20 to 50:50) as eluant.

1. temperatureAfter heating to ambient temperature approx
2. extractionthe mixture is extracted three times with 70 ml of ethyl acetate
3. customThe combined extracts are dried
4. customevaporated down