Potassium Carbonate → 4-bromo-1-(3-chloro-2-methylbenzyl)-6-nitro-2-(trifluoromethyl)-1H-benzo[d]imidazole

Participants

Reaction Conditions

Reaction Steps

Charged a 100 mL round bottom flask containing 4-bromo-6-nitro-2-(trifluoromethyl)-1H-benzo[d]imidazole (4.3 g, 13.87 mmol) dissolved in N,N-Dimethylformamide (DMF) (30 mL) with 1-(bromomethyl)-3-chloro-2-methylbenzene (3.81 g, 17.34 mmol) then added potassium carbonate (4.79 g, 34.7 mmol). The resulting reaction suspension was stirred for 6 h at 90° C., then cooled to RT, and filtered to remove potassium carbonate. The resulting filtrate was concentrated to a small volume (˜10 mL), and diluted with water. The aqueous suspension was extracted with chloroform (3×), the organic extracts were combined, washed with brine, dried over Na2SO4, filtered, and finally concentrated in vacuo. The crude solid was slurried in hexane to provide 4-bromo-1-(3-chloro-2-methylbenzyl)-6-nitro-2-(trifluoromethyl)-1H-benzo[d]imidazole (3.5 g, 7.80 mmol, 56.2% yield). The material was carried onto the nitro reduction without further purification. MS (ES+) m/e: 449.0, 450.8 [M+H]+(bromine pattern). 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 8.55 (d, J=2.02 Hz, 1H) 8.08 (d, J=1.77 Hz, 1H) 7.40 (d, J=8.08 Hz, 1H) 7.04 (t, J=7.96 Hz, 1H) 6.23 (d, J=7.83 Hz, 1H) 5.63 (s, 2H) 2.52 (s, 3H)

Provenance & Evidence