To a degassed toluene (200 mL), 2,4-dibromodibenzo[b,d]thiophen-3-amine (12.15 g, 34.0 mmol), 4,4,5,5-tetramethyl-2-(prop-1-en-2-yl)-1,3,2-dioxaborolane (17.15 g, 102 mmol), benzaldehyde (3.61 g, 34.0 mmol), potassium phosphate (23.51 g, 102 mmol) dicyclohexyl(2′,6′-dimethoxy-[1,1′-biphenyl]-2-yl)phosphine (1.676 g, 4.08 mmol) and Pd2(dba)3 (0.935 g, 1.021 mmol) and water (20 mL) were sequentially added. The solution was refluxed for overnight in an atmosphere of nitrogen and then allowed to cool to room temperature. The reaction was diluted with ethyl acetate and the organic phase was separated from the aqueous phase. The organic phase was dried over sodium sulfate and the solvent was removed under vacuum. The product was chromatographed using silica gel with ethylacetate and hexanes as the eluent. The solvent was removed to give the title compound (9.0, 95%).
