Hydrochloric Acid → 4-(1-(4-(perfluoroethoxy)phenyl)-1H-1,2,4-triazol-3-yl)benzoic acid

Participants

Reaction Conditions

Reaction Steps

In a 250 mL round bottom flask equipped with an overhead stirrer, thermocouple, and nitrogen inlet was added methyl 4-(1-(4-(perfluoroethoxy)phenyl)-1H-1,2,4-triazol-3-yl)benzoate (11.1 g, 26.9 mmol) and THF (100 mL). To this yellow suspension was added water (10 mL) and lithium hydroxide monohydrate (3.4 g, 81 mmol). There was no change in reaction appearance and temperature (20.5° C.). The reaction was stirred at 23° C. for 39 h during which it became a yellow solution. A heating mantle was attached to the reaction flask and the flask was heated to an internal temperature of 60° C. for 2.5 hrs. The reaction was then cooled to 4° C. in an ice bath and water (100 mL) was added, providing a light yellow solution. Concentrated HCl (8.0 g) was added (note: exothermic) which gave a thick white precipitate. The white suspension was stirred at 5° C. for 30 min and then the solid was collected by vacuum filtration and washed with water (2×25 mL). The white wet cake was allowed to dry in air for 3 h, and was then placed into a vacuum oven (50° C., 700 mm Hg vacuum, 16 h). This gave the title compound as a white solid (10.3 g, 96%): mp 227-229° C.; 1H NMR (400 MHz, CDCl3) δ 8.65 (s, 1H), 8.32 (d, J=8.4 Hz, 2H), 8.23 (d, J=8.4 Hz, 2H), 7.84 (d, J=8.9 Hz, 1H), 7.42 (d, J=8.9 Hz, 2H).

Provenance & Evidence