Cesium carbonate → 5,5-dimethyl-1'-{[5-(trifluoromethyl)-2-furyl]methyl}-5,6-dihydrospiro[benzo[1,2-b:5,4-b']difuran-3,3'-indol]-2'(1'H)-one

Participants

Reaction Steps

To a solution of 5,5-dimethyl-5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-2′(1′H)-one (0.09 g, 0.29 mmol) in 2-butanone (10.0 mL) was added 2-bromomethyl-5-(trifloromethyl)furan (0.08 g, 0.35 mmol) followed by cesium carbonate (0.19 g, 0.58 mmol) at 0° C. The mixture was stirred at ambient temperature overnight. The reaction mixture was filtered and the filtrate was concentrated in vacuo. The residue was subjected to column chromatography (ethyl acetate/hexane, 1/5) to give the title compound (0.06 g, 45%): mp 155-160° C.; 1H NMR (300 MHz, CDCl3,) δ 7.29 (t, 1H), 7.19 (d, 1H), 7.07 (t, 1H), 6.97 (d, 1H), 6.73 (t, 1H), 6.42-6.37 (m, 2H), 6.30 (s, 1H), 5.08 (d, 1H), 4.94-4.84 (m, 2H), 4.65 (d, 1H), 4.18 (s, 2H), 1.19 (s, 3H), 1.14 (s, 3H); 13C NMR (75 MHz, CDCl3) δ 177.5, 161.2, 161.0, 152.0, 141.4, 132.5, 130.1, 128.8, 124.2, 123.8, 120.1, 116.4, 112.6, 109.3, 108.7, 93.4, 85.5, 80.6, 57.7, 41.4, 36.9, 27.6, 27.5; MS (ES+) m/z 456.5 (M+1).

Provenance & Evidence