Imidazole → 1-(2-fluoro-4-nitrophenyl)-1H-imidazole

Participants

Reaction Conditions

Reaction Steps

A solution of 2.14 g (31.4 mmol) of imidazole and 10.9 g (62.8 mmol) of dibasic potassium phosphate in 190 mL DMSO was treated with 5.25 g (3.7 mL, 32.9 mmol) of 3,4-difluoronitrobenzene followed by warming at 90° C. for 18 h. The solution was diluted with ethyl acetate and was extracted with water. The water layer was back-extracted with ethyl acetate and the combined organic layers were then extracted with water (2×). The organic layer was dried (Na2SO4) and concentrated in vacuo to afford a brown solid. This material was chromatographed over 250 g of 230-400 mesh silica gel, eluting with dichloromethane, and then with 1% (v/v) methanol in dichloromethane, and finally with 2% (v/v) methanol in dichloromethane. These procedures afforded 6.0 g (92%) of the title compound as a bronze colored solid. 1H NMR (CDCl3): δ 8.17, 7.96, 7.63, 7.35, 7.26.

Provenance & Evidence