4385-75-5

626-55-1

14047-29-1

4385-75-5

Example 157 Synthesis of 4-(pyridin-3-yl)benzoic acid: in a mixed solvent of acetonitrile (40 mL) and water (40 mL), 4-carboxyphenylboronic acid (1.66 g, 10 mmol), 3-bromopyridine (1.72 g, 11 mmol), potassium carbonate (5.5 g, 40 mmol), and bis(triphenylphosphine)palladium(II) chloride (400 mg. 0.37 mmol). The reaction mixture was degassed and displaced three times with nitrogen. Subsequently, the mixture was stirred under reflux conditions for 24 hours. Upon completion of the reaction, the reaction suspension was filtered while hot and the filtrate was concentrated to half of the original volume. The concentrated aqueous phase was washed with dichloromethane. The aqueous phase was adjusted to pH=3 with 1 M hydrochloric acid, the solid was precipitated, filtered and the solid was washed with water. Finally, the resulting solid was dried under vacuum to give 1.7 g of white solid 4-(pyridin-3-yl)benzoic acid in 85% yield.LC-MS (ESI) m/z: 200 (M+1)+.