To a solution of 2-bromochlorobenzene (0.24 mL, 2 mmol) and 3-formylbenzeneboronic acid (0.35 g, 2.2 mmol) in toluene (20 mL) were added 2M aq. sodium carbonate (2.6 mL) followed by (Ph3P)4Pd (0.34 g, 0.3 mmol). The resulting reaction mixture was refluxed for 3 h, cooled and diluted ethyl acetate. The organic phase was washed with water, saturated aq. sodium bicarbonate, brine and dried over sodium sulfate. The filtrate was concentrated in vacuo and the residue obtained was purified by chromatography (hexane:ethyl acetate; 4:1) to yield the title product.
