Sodium Carbonate → Tert-butyl 4-(benzofuran-2-yl)benzoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzoate (1.0 g, 3.3 mmol), 2-bromobenzofuran (0.64 g, 3.3 mmol) and tetrakis(triphenylphosphine) palladium(0) (0.5 g, 0.4 mmol) in a mixed solution of 1,4-dioxane (20 mL) and water (2.0 mL) was added sodium carbonate (1.0 g, 7.2 mmol). The reaction mixture was stirred at 90° C. under nitrogen for 12 hours. After the reaction, it was allowed to cool to room temperature, and concentrated in vacuo, then diluted with ethyl acetate (100 mL), washed with water (100 mL). The organic phase was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated and the residue was purified by column chromatography (silica gel, ethyl acetate/petroleum ether=1:20) to give the pure product tert-butyl 4-(benzofuran-2-yl)benzoate as a white solid (0.65 g, 67%). 1H NMR (300 MHz, CDCl3): δ 8.06 (d, J=8.7 Hz, 2H), 7.90 (d, J=8.4 Hz, 2H), 7.62-7.53 (m, 2H), 7.32-7.25 (m, 2H), 7.14 (s, 1H), 1.62 (s, 9H).

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