反应详情

To a mixture of 0.55 g of N-[5-chloro-2-hydroxy-4-(trifluoromethyl)phenyl]isonicotinamide, 6 ml of tetrahydrofuran and 0.50 g of triphenylphosphine, 0.83 g of 40% toluene solution of diethyl azodicarboxylate was added dropwise at room temperature. The reaction mixture was stirred for 1.5 hours. The reaction mixture was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography, and the resultant crystals were washed with methanol to give 0.11 g of 5-chloro-2-(pyridin-4-yl)-6-(trifluoromethyl)benzoxazole (hereinafter, referred to as “active compound 78”).

1. additionwas added dropwise at room temperature
2. concentrationThe reaction mixture was concentrated under reduced pressure
3. washthe resultant crystals were washed with methanol