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

Participants

Reaction Conditions

Reaction Steps

In 100 ml of toluene, 10.0 g (0.106 mol) of 2-aminopyridine was dissolved. After the solution was cooled to 5° C., 11.84 ml (0.159 mol) of trifluoroacetic acid and subsequently 5.94 ml (0.064 mol) of phosphorus oxychloride were added thereto, followed by stirring at room temperature overnight. Then, 20 ml of toluene was distilled off under reduced pressure. To the reaction liquid, 50 ml of dimethylformamide, 22.03 g (0.16 mol) of potassium carbonate powder, and 17.56 g (0.108 mol) of 2-chloro-5-chloromethylpyridine were added under ice-cooling. Then, distillation was conducted under reduced pressure (60 to 35 hPa) at 50 to 60° C. One hour later, 20 ml of dimethylformamide, 20 ml of toluene, and 4.41 g (0.032 mol) of potassium carbonate powder were further added thereto, and distillation was conducted under reduced pressure (60 to 35 hPa) and 50 to 60° C. for 1.5 hours. The reaction liquid to which 30 ml of methanol was added was added to 250 ml of water of 50° C. Then, 50 ml of water was added thereto, while the vessel was also washed therewith. After being cooled to room temperature, the mixture was stirred for 30 minutes. The crystals were filtered, and washed with 50 ml of water and 30 ml of toluene. The obtained crystals were dried under reduced pressure at 60° C. Thus, 23.69 g of the target compound was obtained (70.6%).

Provenance & Evidence