A mixture of trifluoromethanesulfonic acid 8-chloro-3-(4-chlorophenylsulfanyl)-2,4-dimethylquinolin-5-yl ester (0.31 g), tert-butyl-(1-methoxyvinyloxy)dimethyl silane (0.71 mL), sodium acetate (0.064 g), bis(dibenzylideneacetone) palladium (0.018 g) and 1,1′-bis(diphenylphospino) ferrocene (0) (0.018 g) in N,N-dimethylformamide (4.0 mL) was heated by microwave irradiation at 120° C. for 15 minutes. The mixture was diluted with ethyl acetate, and this solution was washed with saturated aqueous ammonium chloride solution and saturated aqueous sodium chloride solution and then dried over magnesium sulfate. The solvent was removed under reduced pressure and purification of the residue by column chromatography on silica gel, eluting with a mixture of dichloromethane and cyclohexane (1:1 to 2:0 by volume) gave title compound as a pale yellow solid, 0.15 g.
