Reaction Steps
A mixture of (3-bromopyridin-2-yl)methanol (0.100 g, 0.530 mmol) and thionyl chloride (0.070 mL, 0.97 mmol) in dichloromethane (3 mL) and N,N-dimethylformamide (1 drop) was stirred at ambient temperature for 16 h. The reaction mixture was concentrated in vacuo and tetrahydrofuran (5 mL) and N,N-dimethylformamide (5 mL) were added, followed by 2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-2′(1′H)-one (0.121 g, 0.41 mmol), cesium carbonate (0.374 g, 1.15 mmol), and potassium iodide (0.038 g, 0.23 mmol). The mixture was heated at 100° C. for 1 h, allowed to cool to ambient temperature and concentrated in vacuo. The residue was triturated sequentially with water and methanol and further purified by column chromatography and eluted with a 0% to 50% gradient of ethyl acetate in dichloromethane to afford 3′-[(3-bromopyridin-2-yl)methyl]-2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,1′-inden]-2′(3′H)-one (0.113 g, 59%) as a colorless solid: mp 217-218° C.; 1H NMR (300 MHz, DMSO-d6) δ 8.41 (d, 1H, J=4.0 Hz), 8.15 (d, J=8.1 Hz, 1H), 7.24 (m, 1H), 6.50 (s, 1H), 6.43 (s, 1H), 5.13 (ABq, 2H), 4.75 (ABq, 2H), 4.14-4.09 (m, 4H); 13C NMR (75 MHz, DMSO-d6) δ 177.3, 155.0, 152.6, 148.3, 144.6, 143.3, 141.3, 138.2, 132.4, 129.1, 125.1, 123.9, 123.3, 122.1, 120.2, 112.3, 109.7, 99.0, 79.7, 64.7, 64.1, 57.7, 44.7; MS (ES+) m/z 464.6 (M+1), 466.6 (M+1).
