反应详情

2,2-difluoro-2-(fluorosulfonyl)acetic acid (189 μl) was added to an acetonitrile (2 ml) solution containing the mixture (105 mg) of 5-nitro-3-(2H-1,2,3-triazol-2-yl)pyridin-2-ol and 5-nitro-3-(1H-1,2,3-triazol-1-yl)pyridin-2-ol obtained in the 1st step, followed by stirring at room temperature for 21 hours. Subsequently, sodium sulfate (100 mg) and 2,2-difluoro-2-(fluorosulfonyl)acetic acid (126 μl) were added to the solution, followed by stirring at 70° C. for 7 hours. The reaction solution was adjusted to room temperature and a saturated sodium hydrogen carbonate solution was added to the reaction solution, followed by extraction with ethyl acetate. The organic layers were washed with saturated saline and dried over anhydrous sodium sulfate. The solvent was distilled away under reduced pressure and the obtained residue was, purified by silica gel chromatography (n-hexane:ethyl acetate=1:0 to 4:1). A light yellow solid of 2-(difluoromethoxy)-5-nitro-3-(2H-1,2,3-triazol-2-yl)pyridine (15 mg) was thus obtained.

1. customobtained in the 1st step
2. stirringby stirring at 70° C. for 7 hours
3. customwas adjusted to room temperature
4. extractionfollowed by extraction with ethyl acetate
5. washThe organic layers were washed with saturated saline
6. dry with materialdried over anhydrous sodium sulfate
7. distillationThe solvent was distilled away under reduced pressure
8. custompurified by silica gel chromatography (n-hexane:ethyl acetate=1:0 to 4:1)