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-1-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 for 5 min, irradiated for 15 min with microwaves in a microwave reactor (Initiator Sixty, Biotage) and concentrated in a vacuum. The concentrate was dissolved in ethyl acetate, washed with saturated NaHCO3 and saturated NaCl, and dried over magnesium sulfate, followed by vacuum concentration. The residue thus obtained was dissolved in acetic acid (15 mL) and stirred for 5 min before irradiation for 15 min with microwaves in a microwave reactor (Initiator Sixty, Biotage). Again, the reaction solution was cooled to room temperature, vacuum concentrated, dissolved in ethyl acetate, washed with saturated NaHCO3 and saturated NaCl, and dried over magnesium sulfate, followed by vacuum concentration. The residue was separated using column chromatography (developing solvent: chloroform/methanol=30/1) to produce 0.81 g of 2-[4-(3-chloropyridin-2-yl)phenyl]-6-trifluoromethyl-1H-benzoimidazole (yield 90%).

Provenance & Evidence