Pyridine → 1-methyl-2-(3-methylpyridin-4-yl)-5-trifluoromethyl-1H-benzimidazole

Participants

Reaction Conditions

Reaction Steps

A mixture of 0.38 g of N1-methyl-4-trifluoromethylbenzene-1,2-diamine, 0.33 g of 3-methylisonicotinic acid, 0.46 g of WSC and 10 ml of pyridine was stirred for 5 hours while heating at 120° C. After cooling down to room temperature, water was poured, and the mixture was extracted three times with ethyl acetate. The combined organic layers were dried over magnesium sulfate, then, concentrated under reduced pressure. To the residue were added a mixture of 0.57 g of p-toluenesulfonic acid monohydrate and 10 ml of toluene, and the mixture was stirred for 1 hour while heating at 80° C., and stirred for 2 hours while heating at 120° C. After cooling down to room temperature, a saturated sodium hydrogen carbonate aqueous solution was poured, and the mixture was extracted three times with ethyl acetate. The combined organic layers were dried over magnesium sulfate, then, concentrated under reduced pressure. The residue was subjected to silica gel column chromatography to obtain 0.48 g of 1-methyl-2-(3-methylpyridin-4-yl)-5-trifluoromethyl-1H-benzimidazole (hereinafter, referred to as present active compound 6).

Provenance & Evidence