反应详情

2-(4-bromophenyl)imidazole (5.3 g, 23.76 mmol) was taken into THF (100 mL) followed by addition of DIPEA (5 mL, 28.5 mmol) and isobutyl chloroformate (3.4 mL, 26.1 mmol) and the resulting solution was stirred for 30 minutes at room temperature. The solution was then concentrated and the residue partitioned with ethyl acetate and water. The organic phase was washed once with 10% aqueous citric acid, brine then dried over anhydrous magnesium sulfate, filtered and concentrated. The residue was purified by silica gel chromatography (2.5:1 hexanes:ethyl acetate) to give isobutyl 2-(4-bromophenyl)-1H-imidazole-1-carboxylate (3.5 g, 46% yield) as an amorphous residue.

1. concentrationThe solution was then concentrated
2. customthe residue partitioned with ethyl acetate and water
3. washThe organic phase was washed once with 10% aqueous citric acid, brine
4. dry with materialthen dried over anhydrous magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue was purified by silica gel chromatography (2.5:1 hexanes:ethyl acetate)