Sodium Hydroxide → 2-(4-fluorophenyl)-2,3-dihydro-5-methyl-4H-1,2,3-triazol-4-one

Participants

Reaction Steps

2-(4-Fluorophenyl)-5-methyl-2H-1,2,3-triazol-4-yl acetate (i.e. the product of Step B, 7.8 g, 33 mmol) was suspended in methanol (150 mL). A solution of sodium hydroxide (7 M, 22 mL, 140 mmol) was added over several minutes with stirring during which time the mixture became homogeneous and then stirred at 23° C. for 18 h. The reaction was concentrated under reduced pressure to remove excess methanol. The remaining residue was diluted with water (200 mL) and washed with hexanes. The aqueous layer was acidified with concentrated hydrochloric acid during which time a thick creamy precipitate formed. The mixture was diluted with water and stirred for 30 min. The precipitate was filtered and washed well with water. The moist solid was dissolved in ethyl acetate, dried (MgSO4) and concentrated under reduced pressure to afford the title compound (6.1 g) as a beige solid. The title compound was used directly in the next step without further purification.

Provenance & Evidence