反应详情

Dimethyl 2-butylimidazol-4,5-dicarboxylic acid (7.12 g, 29.6 mmol) and 4-iodobenzyl bromide (10.56 g, 35.5 mmol) were dissolved in DMF (50 ml), and 60% oily sodium hydride (1.3 g, 32.5 mmol) was added in small portions while stirring at room temperature. The reaction solution was stirred at room temperature for 2 hours and methanol was added to treat excess sodium hydride. Then the reaction solution was neutralized with 2N HCl and the product was extracted with dichloromethane. The extracted solution was dried over sodium sulfate and concentrated in reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:1) to give the titled compound (11.1 g, 82%) as a tan solid (mp:98-99° C., Rf:0.60 silica gel-ethyl acetate/hexane/=1/1). This has the following NMR spectrum.

1. stirringThe reaction solution was stirred at room temperature for 2 hours
2. extractionthe product was extracted with dichloromethane
3. dry with materialThe extracted solution was dried over sodium sulfate
4. concentrationconcentrated in reduced pressure
5. customThe residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:1)