反应详情

To a solution of 1-methylcyclopropanecarboxylic acid (1.0 g) in tetrahydrofuran (50 ml), 3-trifluoromethyl-4-difluoromethoxyaniline (2.25 g) was added, and a solution of N,N'-dicyclohexylcarbodiimide (DCC) (2.2 g) in tetrahydrofuran was dropwise added while stirring. After several minutes, the by-produced N,N'-dicyclohexylurea (DCU) was eliminated by filtration. To the filtrate, acetic acid (2 ml) was added to decompose excessive DCC, followed by elimination of DCU. The resultant filtrate was extracted with ether, and the extract was washed with 1 N hydrochloric acid, sodium hydrogen carbonate solution and saturated sodium chloride solution, dried over anhydrous magnesium sulfate and concentrated. The crude crystals (2.85 g) were recrystallized from ethanol to give N-(3-trifluoromethyl-4-difluoromethoxyphenyl)-1-methylcyclopropanecarboxamide (2.5 g). M.P., 39°-40° C.

1. waitAfter several minutes
2. filtrationthe by-produced N,N'-dicyclohexylurea (DCU) was eliminated by filtration
3. additionTo the filtrate, acetic acid (2 ml) was added
4. extractionThe resultant filtrate was extracted with ether
5. washthe extract was washed with 1 N hydrochloric acid, sodium hydrogen carbonate solution and saturated sodium chloride solution
6. dry with materialdried over anhydrous magnesium sulfate
7. concentrationconcentrated
8. customThe crude crystals (2.85 g) were recrystallized from ethanol