A mixture of 3-chloro-7-methoxyisoquinoline (Intermediate 12) (300 mg, 1.55 mmol), 4-carboxy-2-fluorophenylboronic acid (285 mg, 1.55 mmol), K2CO3 (642 mg, 4.65 mmol) and Pd(dppf)Cl2 (30 mg, 0.037 mmol) in DEGME (7 mL) and water (2 mL) was stirred under N2 atmosphere at 120° C. for 3 hours. The resulting mixture was cooled to room temperature and filtered. The filtrate was acidified with aqueous HCl (2M) until pH=6 and filtered. The solid was dried under reduced pressure to give 3-fluoro-4-(7-methoxyisoquinolin-3-yl)benzoic acid (140 mg, yield: 30%) as off-white solid.
