[F:1][C:2]1[CH:9]=[CH:8][CH:7]=[C:4]([CH:5]=[O:6])[C:3]=1[OH:10].[C:11](=O)([O-])[O-].[Cs+].[Cs+].IC>CN(C)C=O.C(OCC)C>[F:1][C:2]1[C:3]([O:10][CH3:11])=[C:4]([CH:7]=[CH:8][CH:9]=1)[CH:5]=[O:6]A mixture of 3-fluorosalicylaldehyde (3.52 g, 25.12 mmol) and cesium carbonate (20.46 g, 62.81 mmol) in N,N-dimethylformamide (30 mL) is treated with iodomethane (3.13 mL, 50.2 mmol) and stirred at room temperature under nitrogen for 2 h. The reaction mixture is diluted with diethyl ether (150 mL) and washed with 0.5 M hydrochloric acid (2×150 mL). The organic portion is dried over anhydrous sodium sulfate, filtered, and concentrated to afford 3.42 g (88%) of the title compound as a clear oil. 1H NMR (400 MHz, CDCl3) δ 7.59 (d, 1H), 7.32 (dd, 1H), 7.04 (m, 1H), 4.04 (s, 3H).
Wird geladen…