Under argon atmosphere, a mixture of methyl 7-bromo-1,1-dioxo-2,3-dihydro-1-benzothiepine-4-carboxylate (0.80 g), 4-(1-pyrrolidinyl)phenyl borate (508 mg) and potassium carbonate (0.67 g) in toluene/ethanol/water (30/3/3 ml) was stirred at room temperature for 1 hour. To the mixture was added tetrakistriphenylphosphinepalladium (0.14 g), and the mixture was refluxed for 17 hours, cooled, extracted with ethyl acetate, washed with saturated brine, dried with magnesium sulfate and concentrated under reduced pressure to give crystals, which were collected by filtration. The crystals were washed with diisopropylether to give yellow crystals of methyl 7-[4-(1-pyrrolidinyl)phenyl]-1,1-dioxo-2,3-dihydro-1-benzothiepine-4-carboxylate (323 mg).
