Dimethyl Sulfoxide → 1-(4-Bromobenzyl)-1H-imidazole

Participants

Reaction Steps

Dimethyl sulphoxide (20 mL, dried over 4 Å molecular sieves) was added to potassium hydroxide (2.24 g, 0.04 mol, crushed pellets) and the mixture was stirred for 5 min. Imidazole (0.5718 g, 0.0084 mol) was then added and the mixture was stirred for 2 hours. 4-Bromobenzyl bromide (3.25 g, 0.013 mol) was added and the mixture was cooled briefly and stirred for a further hour before adding water (20 mL). The mixture was extracted with ether (3×100 mL) and each extract was washed with water (3×50 mL). The combined ether layers were dried over CaCl2 and the solvent was removed in vacuo. The residue was chromatographed on silica gel with CHCl3/MeOH (30:1) plus 0.05% formic acid as eluent yielding the sub-title compound (1.275 g, yield: 53%).

Provenance & Evidence