反应详情

To a mechanically stirred solution of 4,5-dibromo-2-ethylimidazole (25.4 g, 0.1 mole,) in anhydrous DMF (250 mL) was treated with K2CO3 (69.1 g, fw=138.2, 0.5 moles, 5 equiv.) followed by dropwise addition of benzyl chloromethyl ether (18.5 g, 0.11 moles, 93% pure, TCI, fw=156.61) and stirred overnight at room temp under nitrogen for 20 h. TLC (30:70 EtOAc/hexane) revealed absence of starting material imidazole (Rf=0.2) along with formation of product (Rf=0.71). The reaction mixture was filtered, washed the solid with dichloromethane and the combined filterate was evaporated under reduced pressure and purified the crude (47 g) by flash column chromatography (dichloromethane eluent) to afford 31.75 g (85%) of colorless oil. Mass spectrum (m/z=375, M+H).

1. filtrationThe reaction mixture was filtered
2. washwashed the solid with dichloromethane
3. customthe combined filterate was evaporated under reduced pressure
4. custompurified the crude (47 g) by flash column chromatography (dichloromethane eluent)