A mixture of tert-butyl 9-bromo-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (200 mg, 0.609 mmol), cyclopropylboronic acid (78.5 mg, 0.914 mmol), saturated aqueous sodium carbonate solution (3 ml), and tetrakis(triphenylphosphine)palladium(0) (19.0 mg, 0.0172 mmol) in dimethoxyethane (5 ml) was stirred at 90° C. for 12 hr under a nitrogen atmosphere. The reaction mixture was poured into water, and the mixture was extracted with ethyl acetate. The extract was washed with water, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (hexane:ethyl acetate=1:1) to give the desired product (70.0 mg, 39.8%) as an oil.
