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

Participants

Reaction Steps

To a 100 mL round bottomed flask containing DMF (17 mL) was added 4-bromo-2-(difluoromethyl)-6-nitro-1H-benzo[d]imidazole (2.3 g, 7.88 mmol), 1-(bromomethyl)-3-chloro-2-methylbenzene (2.4 g, 10.93 mmol) and potassium carbonate (2.3 g, 16.64 mmol). The resultant suspension was heated to 70° C. and after stirring for 20 minutes LC/MS indicated that almost all starting material had been consumed so the heat was turned off and the reaction was allowed to stir overnight at rt. The next day the mixture was diluted with 75 mL H2O and stirred for 10 minutes resulting in the precipitation of a light brown solid. The solid was isolated by filtration and was washed 3× with H2O and 3× with hexanes to provide 4-bromo-1-(3-chloro-2-methylbenzyl)-2-(difluoromethyl)-6-nitro-1H-benzo[d]imidazole (4.2 g, 8.39 mmol, 107% yield) as light brown solid. The NMR and LC/MS were consistent with desired product and the crude product will be used in subsequent reactions without further purification. LC/MS: MS (ES+) m/e 431.9 [M+H]+; 1H NMR (400 MHz, DMSO-d6) δ ppm 8.76 (d, J=2.02 Hz, 1H), 8.45 (d, J=2.02 Hz, 1H), 7.32-7.68 (m, 2H), 6.99-7.12 (m, 1H), 6.06 (d, J=7.58 Hz, 1H), 5.90 (s, 2H), 2.47 (s, 3H)

Provenance & Evidence