Synthesis
Magnesium powder and a small pellet of iodine were added to the reaction flask, which was dried at high temperature, and the reaction system was then nitrogen-protected (air in the reaction system was replaced with nitrogen) through a double-row tube. Anhydrous tetrahydrofuran and 2-bromo-5-fluorobenzotrifluoride were then added to the reaction system under nitrogen atmosphere and the resulting mixture system was heated to reflux in an oil bath and the reaction was stirred at reflux for 2 hours to prepare the corresponding format reagents. The reaction system was cooled to room temperature and then the nitrogen in the reaction system was replaced with the corresponding carbon dioxide and the resulting reaction mixture was stirred and reacted at room temperature overnight. After the reaction, hydrochloric acid was added to the reaction system to acidify the reaction system, the reaction mixture was extracted with ethyl acetate and water, the organic layer was separated and dried, the organic layer was concentrated and the residue was purified by silica gel column chromatography to obtain the target molecule 4-fluoro-2-(trifluoromethyl)benzoic acid.
