14.7 mmol of diethyl(pyrid-4-yl)borane, 22 mmol of 5-bromo-2,3-dihydro[1,4]benzodioxine, 44.1 mol of KOH in powder form, 7.4 mmol of tetrabutylammonium bromide and 0.74 mmol of tetrakis(triphenylphosphine)palladium in 75 ml of tetrahydrofuran are mixed at room temperature, and the mixture is then refluxed for 24 hours. 225 ml of ethyl acetate are added and the mixture is washed with a saturated sodium chloride solution. Drying is carried out over MgSO4, followed by evaporation and purification over a silica column (eluant CH2Cl2,then CH2Cl2 /CH3COOC2H5 80/20).
