Into 100 mL toluene were added methyl 2-(2-methyl-1H-indol-3-yl)acetate (4.9 g, 24.1 mmol), p-nitro benzyl bromide (5.18 g, 24.0 mmol), cesium carbonate (9.38 g, 28.8 mmol), and cetyl tributyl phosphonium bromide (1.58 g, 3.1 mmol). Upon completion of addition, it was reacted at 110° C. for 6 hours. Upon completion of the reaction, it was cooled, water was added, and extracted with diethyl ether. The extract was washed with water. The organic phase was rotate evaporated to dryness, and purified by preparative liquid phase to obtain the product 300 mg, at a yield of 3.7%.
