Trifluoroacetic acid → N-[1-[1-(6-Chloro-3-pyridyl)ethyl]-2-pyridylidene]-2,2,2-trifluoroacetamide

Participants

Reaction Conditions

Reaction Steps

To 13.68 g (0.12 mol) of trifluoroacetic acid, 1.5 mL of dimethylformamide was added. Then, 14.28 g (0.12 mol) of thionyl chloride was added to the mixture, which was heated to 65° C. Trifluoroacetyl chloride generated therefrom was bubbled into a solution which was obtained by dissolving 9.4 g (0.1 mol) of 2-aminopyridine in 50 mL of N-methylpyrrolidone, and which was cooled to −10° C., and the mixture was stirred for 1 hour. To the reaction liquid, 100 mL of toluene, 48.3 g (0.35 mol) of potassium carbonate powder, and 16.52 g (0.102 mol) of 2-chloro-5-chloromethylpyridine were added, and distillation was conducted under reduced pressure (36 hPa) at 50 to 60° C. for 3 hours. To the reaction liquid, 20 mL of methanol was added, and the mixture was added to 300 ml of water heated to 50° C., while the vessel was also washed. The mixture was stirred at room temperature for 1.5 hours. Then, the crystals were filtered, and washed with 100 mL of water and 150 mL of toluene. The obtained crystals were dried under reduced pressure at 45° C. Thus, 16.8 g of the target compound was obtained (Percentage Yield: 53.3%).

Provenance & Evidence