反应详情

温度

120 °C

To a suspension of 5-acetyl-1-(3-(methoxycarbonyl)phenyl)benzimidazole (prepared in analogy with Example 26) (0.6 g, 2.04 mmol) in anhydrous DMF (5 ml) was added dimethylformaldehyde dimethylacetal (0.43 ml, 3.24 mmol) and the mixture was heated to 120° C. under a stream of nitrogen overnight. The cooled mixture was poured into ice-water (25 ml) and the precipitate was filtered off and purified by column-chromatography on silica gel using a mixture of ethyl acetate and methanol (9:1 v/v) as the eluent to yield 5-(3-dimethylaminopropenoyl)-1-(3-(ethoxycarbonyl)phenyl)-benzimidazole (0.44 g, 62%).

1. filtrationthe precipitate was filtered off
2. custompurified by column-chromatography on silica gel using
3. additiona mixture of ethyl acetate and methanol (9:1 v/v) as the eluent