Triethylamine → 2-Fluoro-5-(4-methylbenzoxazol-2-yl)nitrobenzene

Participants

Reaction Steps

To a suspension of 3-fluoro-2-nitrobenzoic acid (1.00 g, 5.40 mmol) and DMF (1 drop) in toluene (10 mL) was added thionyl chloride (0.78 g, 6.56 mmol) and this was stirred at reflux for 3 hours. After the reaction was complete, concentration at reduced pressure gave a residue that was added to 2-hydroxy-6-methylaniline (0.66 g, 5.4 mmol), triethylamine (0.66 g, 6.5 mmol) and tetrahydrofuran (5 mL), and this was stirred at room temperature for 3 hours. After the reaction was complete, water (50 mL) was added, and this was extracted with ethyl acetate. After the organic layer was dried over anhydrous sodium sulfate, filtration and concentration gave crystals that were added to toluene (20 mL), to which p-toluenesulfonic acid hydrate (1.14 g, 5.99 mmol) was next added and this was stirred at reflux for 2 hours. After concentration of the solvent at reduced pressure, water (5 mL) was added, after which this was extracted with ethyl acetate. The organic layer obtained was dried over anhydrous sodium sulfate, after which it was filtered and concentrated to yield the title compound (0.50 g, 37% yield) as a light brown solid.

Provenance & Evidence