4-Bromo-3-fluorobenzenamine (2.51 g, 13 mmol) and 5-isoquinolineboronic acid (4.23 g, 24 mmol) were suspended in toluene (35 ml) and EtOH (35 ml) and tetrakis(triphenylphosphine)palladium (812 mg, 0.70 mmol) was added, followed by 10% aqueous sodium carbonate (40 ml). The flask was fitted with a reflux condenser and placed in a preheated oil bath (110 C) and stirred under nitrogen for 4 hours. The reaction was then cooled to room temperature, partially concentrated, and diluted with water. The aqueous phase was extracted with DCM, and the organic extracts were combined, dried over sodium sulfate, filtered, concentrated, and purified on silica gel (50:1->30:1->20:1 DCM/MeOH). The fractions with product were collected, concentrated, and washed with DCM and hexanes. The remaining solid was dried under high vacuum to afford the desired 3-fluoro-4-(isoquinolin-5-yl)benzenamine (2.568 g, 10.78 mmol, 94% purity, 82% yield). MS (ESI pos. ion) m/z: 497 (MH+). Calc'd exact mass for C15H11FN2: 239. 1H NMR (400 MHz, CDCl3): 9.30 (s, 1H), 8.50 (dd, J=6.0 Hz, 2.0 Hz, 1H), 8.02-7.96 (m, 1H), 7.68-7.63 (m, 2H), 7.58-7.54 (m, 1H), 7.16 (dt, J=8.0 Hz, 2.0 Hz, 1H), 6.61 (dt, J=8.0 Hz, 2.0 Hz, 1H), 6.56 (dt, J=11.5 Hz, 2.0 Hz, 1H), 3.93 (br s, 2H).
