Diisopropylethylamine → HCID 11646459, compound

Participants

Reaction Steps

0.44 g (2.5 mmol) 4-trifluoromethylbenzene-1,2-diamine, 1.0 mL (5.0 mmol) diisopropylethylamine and 1.1 g (6 mmol) O-(7-azabenzotriazol-yl)-N,N,N′,N′-tetramethyleuronium hexafluorophosphate were added to a solution of 0.59 g (2.5 mmol) 4-(3-chloropyridin-2-yl)benzoic acid in 25 mL dimethylformamide, which was then stirred at room temperature for 16 hours and vacuum concentrated. The concentrate thus obtained was dissolved in ethyl acetate, washed with saturated NaHCO3 and saturated NaCl, dried over magnesium sulfate, and concentrated in a vacuum. The residue was dissolved in acetic acid/toluene (15 mL/1.5 mL) and stirred at 75° C. for 3 hours, followed by vacuum concentration. Again, the concentrate was dissolved in ethyl acetate, washed with saturated NaHCO3 and saturated NaCl, dried over magnesium sulfate, and vacuum concentrated. The residue was separated using column chromatography (developing solvent: chloroform/methanol=30/1) to produce 0.77 g of 2-[4-(3-chloropyridin-2-yl)phenyl]-6-trifluoromethyl-1H-benzoimidazole (yield 82%).

Provenance & Evidence