Cesium carbonate → 5-fluoro-2-(2H-1,2,3-triazol-2-yl)benzoic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 2H-1,2,3-triazole (CAS number 288-36-8; 4.0 g, 57.97 mmol) in DMF (14.0 ml) was added cesium carbonate (18.84 g, 57.97 mmol), trans-1-N,2-N-dimethylcyclohexane-1,2-diamine (0.510 g, 5.797 mmol), copper(I) iodide (0.276 g, 1.449 mmol) and 5-fluoro-2-iodobenzoic acid (CAS number 52548-63-7; 7.71 g, 28.98 mmol) at 0-10° C. The resulting reaction mixture was then heated with microwave irradiation at 125° C. for 15 hours with stirring. The reaction mass was poured into water and the product was extracted into ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate and concentrated in vacuo. This was then purified by column chromatography (silica, 0-3% methanol/DCM) to obtain 5-fluoro-2-(2H-1,2,3-triazol-2-yl)benzoic acid (Intermediate 8) (also commercially available CAS number 1186050-64-5) and crude 5-fluoro-2-(1H-1,2,3-triazol-1-yl)benzoic acid (Intermediate 9).

Provenance & Evidence