Potassium Carbonate → 3-(2-Methoxyphenyl)-4,5-methylenedioxybenzaldehyde

Beteiligte Stoffe

Reaktionsschritte

A mixture of 3-bromo-4,5-methylenedioxybenzaldehyde (2.51 g, 10.97 mmol), 2-methoxyphenylboronic acid (2.00 g, 13.16 mmol) and potassium carbonate (3.41 g, 24.68 mmol) in 1,2-dimethoxyethane (70 mL) and water (3.5 mL) was degassed with argon for 30 minutes. Tetrakis(triphenylphosphine)palladium(0) (0.63 g, 0.548 mmol) was added and the mixture heated at reflux under argon overnight. The solution was cooled to room temperature, diluted with ethyl acetate (100 mL) and washed successively with water (50 mL) and brine (50 mL), dried over anhydrous magnesium sulfate, filtered and evaporated. The residue was purified on silica gel (eluent: hexane:ether, 9:1) to give 0.910 g of 3-(2-methoxyphenyl)-4,5-methylenedioxybenzaldehyde (32%) as a white solid. 1H NMR (300 MHz; CDCl3): δ 3.84 (s, 3H); 6.07 (s, 2H); 7.00–7.10 (m, 2H); 7.31 (brs, 1H); 7.30–7.45 (m, 2H); 7.53 (brs, 1H); 9.83 (s, 1H).

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