反应详情

A stirred mixture of 2-styryl-1H-benzimidazole (220 mg, 1 mmol), 2-bromothiazole (328 mg, 2 mmol), potassium carbonate (138 mg, 1 mmol), copper bronze (20 mg) and nitrobenzene (10 ml) was heated to reflux under a nitrogen atmosphere for 7 h. The cooled reaction mixture was diluted with ethyl acetate (150 ml) and filtered through a pad of celite. The filtrate was washed consecutively with water (50 ml), and brine (50 ml), dried (magnesium sulfate) and concentrated to dryness. Column chromatography (silica gel, 100 g; n-hexane/ethyl acetate (9/1 to 3/1)) gave 199 mg of the titled compound as an orange oil, which was solidified on standing at room temperature. Recrystallization from isopropyl ether gave 117 mg (39%) of the titled compound as colorless crystals. MW: 303.39; mp: 99.0-99.5° C.; 1H-NMR (CDCl3) δ: 8.01 (1H. d, J=15.8 Hz), 7.91 (1H, d, J=3.7 Hz), 7.85-7.80 (1H, m), 7.69-7.64 (1H, m), 7.59-7.54 (2H, m), 7.51 (1H, d, J=3.7 Hz), 7.40 (1H, d, J=15.8 Hz), 7.42-7.29 (5H, m).

1. temperaturewas heated
2. temperatureto reflux under a nitrogen atmosphere for 7 h
3. customThe cooled reaction mixture
4. filtrationfiltered through a pad of celite
5. washThe filtrate was washed consecutively with water (50 ml), and brine (50 ml)
6. dry with materialdried (magnesium sulfate)
7. concentrationconcentrated to dryness