General procedure for the synthesis of 2-(2-bromopyridin-4-yl)acetic acid from ethyl 2-(2-bromopyridin-4-yl)acetate: to a mixture of THF (5 mL), MeOH (10 mL) and water (5 mL) containing ethyl 2-(2-bromopyridin-4-yl)acetate (1.00 g, 4.10 mmol) was added lithium hydroxide (294 mg, 12.3 mmol). The reaction mixture was stirred at 20 °C for 10 min. Upon completion of the reaction, THF and MeOH were removed by vacuum concentration and the residue was diluted with 10 mL of water. Subsequently, the aqueous phase was acidified with 2N HCl solution to pH = 2. The mixture was filtered, the filter cake was collected and dried under vacuum to afford the target product 2-(2-bromopyridin-4-yl)acetic acid (850 mg, 90% yield) as a white solid.LCMS analysis resulted in (ES+) m/z (M+H)+ = 217.9 and retention time tR = 0.539 min.
