5-(trifluoromethyl)-4H-1,2,4-triazol-3-amine → N-(1,4-dioxaspiro[4.5]dec-8-yl)-5-(trifluoromethyl)-1H-1,2,4-triazol-3-amine

Participants

Reaction Steps

To a solution of 5-(trifluoromethyl)-1H-1,2,4-triazol-3-amine (12.19 g) and 1,4-dioxaspiro[4.5]decan-8-one (12.49 g) in acetic acid (180 mL) was added sodium triacetoxyborohydride (25.43 g), and the mixture was stirred at room temperature for 3 days. The solvent was evaporated under reduced pressure, the residue was diluted with saturated aqueous sodium hydrogen carbonate solution, and the mixture was extracted with ethyl acetate-isopropyl alcohol (3:1). The extract was washed with saturated brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure, and the residue was purified by silica gel chromatography [eluent: methanol/ethyl acetate=0/100→10/90 (volume ratio)] and crystallized from diisopropyl ether to give the title compound as a colorless solid (9.88 g, 42%).

Provenance & Evidence