To a solution of 107 mg of tert-butyl 4-(3-bromo-2-fluorobenzoyl)piperazine-1-carboxylate in 2.0 ml of toluene and 0.1 ml of water was added 72 mg of cyclopropylboronic acid, 3.2 mg of palladium acetate, 0.052 ml of tricyclohexylphosphine (15% toluene solution) and 207 mg of potassium phosphate, successively. The reaction solution was stirred at 150° C. for 10 minutes using a microwave reaction apparatus. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The organic layer was washed with brine and then concentrated. The residue was purified by a silica gel column chromatography (eluent: hexane to hexane/ethyl acetate=1/1) to give the title compound.
