Hydrazine hydrate (1:1) → HCID 178506330、化合物

1.25 g of hydrazine hydrate was dissolved to 45 ml of ethanol, and it was cooled to 0° C. 5.38 g of ethyl 2,2,3,3,3-pentafluoropropionate was dropped to it over the period of 15 minutes, followed by stirring at 0° C. for 1 hour. 2.61 g of formamidine acetic acid salt was added to the reaction mixture, followed by stirring at room temperature for 30 minutes. The reaction mixture was concentrated under reduced pressure. 50 ml of acetic acid was added to the residue, followed by stirring at 100° C. for 5 hours. The reaction mixture was concentrated under reduced pressure. Saturated aqueous solution of sodium hydrogen carbonate was added to the residue so as to be around pH 6. And then it was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was subjected to silica gel column chromatography to obtain 2.98 g of 3-pentafluoroethyl-1H-1,2,4-triazole.