A mixture of (3-(trifluoromethyl)pyridin-2-yl)methanol hydrochloride (0.324 g, 1.52 mmol) and thionyl chloride (0.174 mL, 2.39 mmol) in anhydrous dichloromethane (10 mL) was stirred at ambient temperature for 16 h. The reaction mixture was concentrated in vacuo and anhydrous N,N-dimethylformamide (10 mL) was added. To this mixture was added 2,3-dihydrospiro[furo[2,3-f][1,4]benzodioxine-7,3′-indol]-2′(1′H)-one (0.300 g, 1.01 mmol), cesium carbonate (0.926 g, 2.84 mmol), potassium iodide (0.094 g, 0.57 mmol) and anhydrous N,N-dimethylformamide (15 mL) and the mixture was heated at 90° C. for 1 h. The reaction mixture was allowed to cool to ambient temperature, concentrated in vacuo, and the resulting residue was taken up in water (50 mL), sonicated and filtered. The solid was purified by column chromatography and eluted with a 0% to 40% gradient of ethyl acetate in dichloromethane followed by recrystallization from methanol to afford 1′-{[3-(trifluoromethyl)pyridin-2-yl]methyl}-2,3-dihyrospiro[furo[2,3-f][1,4]benzodioxine-7,3′-indol]-2′(1′H)-one (0.123 g, 27%) as a colorless solid: mp 206-207° C.; 1H NMR (300 MHz, DMSO-d6) δ 8.72 (d, J=4.4 Hz, 1H), 8.24 (d, J=7.9 Hz, 1H), 7.55 (dd, J=7.8, 5.0 Hz, 1H), 7.26-7.20 (m, 2H), 7.01 (dd, J=11.3, 3.8 Hz, 1H), 6.88 (d, J=7.6 Hz, 1H), 6.36 (s, 2H), 5.22 (ABq, 2H), 4.83 (ABq, 2H), 4.27 (s, 4H); 13C NMR (75 MHz, DMSO-d6) δ 177.0, 152.6, 152.4, 148.7, 144.6, 142.9, 134.9, 131.7, 129.1, 128.6, 123.5, 123.0, 122.8, 122.6, 122.5, 122.0, 114.8, 110.0, 108.9, 80.1, 64.1, 63.9, 57.3, 41.8; MS (ES+) m/z 455.0 (M+1).
