A solution of 4-bromoanisole (0.89 g, 5.0 mmol) in 9:1 Et2O/THF (10 ml) was added to magnesium turnings (0.105 g, 5.0 mmol), and the resulting mixture was allowed to stir for 30 min. The resultant 4-methoxyphenyl magnesium bromide was added dropwise to a solution of ethyl 3-(3,4-methylenedioxyphenyl)-1-oxoindene-2-carboxylate (0.77 g, 2.4 mmol) in 10:1 Et2O/THF (55 ml) at 0° C. The resulting mixture was stirred at 0° C. for 1 h and was then partitioned between EtOAc and 1M HCl. The aqueous phase was extracted with EtOAc, and the combined organic extracts were washed successively with 5% aqueous NaHCO3 and saturated aqueous NaCl and dried (MgSO4). The solvent was removed under reduced pressure, and the residue was purified by flash chromatography on silica gel, eluting with 10% EtOAc/hexanes to afford the title compound as a yellow glassy solid (0.80 g, 80%).
