A solution of tetrakis(triphenylphosphine)palladium (0.05 g) and sodium carbonate (0.7 g) in water (5 mL) was sequentially added to a stirred solution of o-bromobenzotrifluorotoluene (0.7 g, 2.75 mmol) and 4-formylbenzeneboronic acid (0.5 g, 3.3 mmol) in dioxane (20 mL) under nitrogen protection and at 80 °C. The reaction mixture was stirred at 100±5°C for 6 hours. Upon completion of the reaction, the solvent was removed by evaporation and the residue was diluted to 50 mL with ethyl acetate and washed with deionized water. The solvent was again removed by evaporation and the residue was purified by silica gel column chromatography (FCC) to afford 2'-(trifluoromethyl)-[1,1'-biphenyl]-4-carbaldehyde (0.61 g, 88% yield) as a milky white solid.1H-NMR (CDCl3) δ: 7.49 (d, 1H, J = 7.41 Hz); 7.48 (d, 2H, J = 8.13 Hz); 7.61-7.53 (m, 2H); 7.76 (d, 1H, J = 7.8 Hz); 7.91 (d, 2H, J = 8.34 Hz); 10.07 (s, 1H).
