Ethanol → 4-Ethoxy-7-nitro-2,5-bis(trifluoromethyl)benzimidazole

Participants

Reaction Steps

4-Chloro-7-nitro-2,5-bis(trifluoromethyl)benzimidazole (3.0 grams; 0.09 mole) was added to about 100 milliliters of ethanol, and the mixture was then refluxed overnight (3.0 grams) and the starting material was recovered. Sodium (.42 gram; 0.018 mole) was added to 100 milliliters of ethanol, and the recovered 4-chloro-7-nitro-2,5-bis(trifluoromethyl)benzimidazole was added at room temperature and the resulting reaction mixture was stirred at room temperature over a weekend. TLC showed only the starting material, so the reaction mixture was heated to reflux and refluxed overnight. The reaction mixture was then poured into water, acidified, and extracted with ethyl acetate. The extract was dried over magnesium sulfate and solvent removed by evaporation to obtain the desired 4-ethoxy-7-nitro-2,5-bis(trifluoromethyl)benzimidazole. After recrystallization from a mixture of ethanol and water, it melted at 144°-46°C. Analysis, Calc.: C, 38.50; H, 2.06; N, 12.24 Found: C, 38.65; H, 2.26; N, 12.36

Provenance & Evidence