Step 2. Synthesis of 4-(pyridin-3-yloxy)benzoic acid. Methyl 4-(pyridin-3-yloxy)benzoate (0.8 g) was dissolved in methanol (10 mL) and aqueous sodium hydroxide solution (2 mL) was added. The reaction mixture was stirred at 75°C for 1 hour. Upon completion of the reaction, it was neutralized with 1N hydrochloric acid (10 mL) and subsequently extracted with ethyl acetate (EtOAc). The organic layers were combined, dried over anhydrous sodium sulfate (Na2SO4) and concentrated under reduced pressure to afford 4-(pyridin-3-yloxy)benzoic acid (0.8 g, 93% yield) as a white solid. LC-MS analysis showed the molecular ion peak of the target compound m/z: 215 ([M+H]+).
