反应详情

温度

90 °C

Through a mixture of 2,4,5-tribromo-1-(2-trimethylsilanyl-ethoxymethyl)-1H-imidazole [Lipshutz et al. (Tet Lett 1992, 33, 5865-5868)] (3.75 g, 7.09 mmol) and phenyl boronic acid (865 mg, 7.09 mmol) in 2 M aqueous sodium carbonate (7.09 mL) and a 5:1 mixture of toluene:methanol (168 mL) was bubbled nitrogen gas for 10 min. Palladium tetrakis triphenylphosphine (820 mg, 0.71 mmol) was added to the mixture that was then heated under nitrogen at 90° C. for 2 h. To the reaction mixture was added 4-methoxy phenyl boronic acid (1.19 g, 7.80 mmol) and another 2 M aqueous sodium carbonate (7 mL). The mixture was refluxed 4 h. The mixture was then concentated in vacuo and purified by flash column chromatography (silica gel, 20% ethyl acetate in hexanes) to provide the title compound as an oil (1.26 g, 39% yield). MS m/e 461; HPLC retention time 4.31 min (Method A).

1. custommethanol (168 mL) was bubbled nitrogen gas for 10 min
2. temperatureThe mixture was refluxed 4 h
3. custompurified by flash column chromatography (silica gel, 20% ethyl acetate in hexanes)