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

Participants

Reaction Conditions

Reaction Steps

In a 250 mL round bottomed flask equipped with an overhead stirrer, T-type thermocouple, and nitrogen inlet were 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 were added water (10 mL) and lithium hydroxide.monohydrate (LiOH.H2O; 3.4 g, 81 mmol). The reaction was stirred at 23° Cfor 39 h during which time it became a yellow solution. The solution was warmed to 60° C. and stirred at 60° C. until complete by LC-MS. The reaction was cooled to 4° C. in an icebath and water (100 mL) was added to give a light yellow solution. Concentrated HCI (8.0 g) was added (note: exothermic) resulting in a thick white precipitate. The white suspension was stirred at 5° C. for 30 min and then the solid was collected by vacuum filtration. The filter cake was washed with water (2×25 mL), air dried for 3 h, and dried under vacuum (700 mm Hg) at 50° C. for 16 h to give the title compound as a white solid (10.3 g, 96%): mp 227-229° C.; 1H NMR (400 MHz, CDCI3) 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