Tetrahydrofuran → 2-(Pyridin-4-yl)-5-(trifluoromethylthio)benzoxazole

Participants

Reaction Steps

To a mixture of 0.69 g of N-[2-hydroxy-5-(trifluoromethylthio)phenyl]isonicotinamide, 9 ml of tetrahydrofuran, and 0.63 g of triphenylphosphine, 1.05 g of 40% toluene solution of diethyl azodicarboxylate was added dropwise at room temperature and stirred for three hours. To the mixture, 0.21 g of triphenylphosphine and 0.35 g of 40% toluene solution of diethyl azodicarboxylate were added. The reaction mixture was stirred for further two 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 0.17 g of 2-(pyridin-4-yl)-5-(trifluoromethylthio)benzoxazole (hereinafter, referred to as “active compound 76”).

Provenance & Evidence