Reaction Steps
A mixture of 4′-bromo-1′-{[5-(trifluoromethyl)-2-furyl]methyl}-5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-2′(1′H)-one (0.11 g, 0.21 mmol), pyrimidine-5-boronic acid (0.04 g, 0.33 mmol), tetrakis(triphenylphosphine)palladium(0) (0.03 g, 0.02 mmol), 2.00 M sodium carbonate (1.00 mL) and 1,2-dimethoxyethane (10.0 mL) was heated at reflux for 16 h under nitrogen. After the organic solvent was evaporated in vacuo, the black residue was extracted with ethyl acetate (3×35.0 mL). The combined organic layers was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated in vacuo. The residue was subjected to column chromatography eluting with ethyl acetate:hexane (35%) to afford the title compound (0.03 g, 26%): mp 263-266° C.; 1H NMR (300 MHz, CDCl3) δ 9.10 (s, 1H), 8.14 (s, 2H), 7.39 (t, 1H), 7.10, (d, 1H), 6.87 (d, 1H), 6.76 (s, 1H), 6.51 (s, 1H), 6.46 (s, 1H), 6.07 (s, 1H), 5.03 (ABq, 2H), 4.62-4.48 (m, 2H), 4.58 (ABq, 2H), 3.01 (t, 2H); 13C NMR (75 MHz, CDCl3) δ 177.3, 162.5, 161.0, 157.4, 155.9, 151.6, 142.2, 141.7, 132.8, 132.3, 131.3, 129.3, 125.7, 120.6, 120.2, 118.3, 117.0, 112.7, 109.7, 109.4, 93.5, 78.9, 72.5, 57.7, 37.1, 28.9; MS (ES+) m/z 506.5 (M+1).
