Bromine → 2-Bromo-3,5-dimethoxybenzaldehyde

Participants

Reaction Conditions

Reaction Steps

3,5-dimethoxybenzaldehyde (12.6 g, 76 mmol) was dissolved in acetic acid (350 mL). The resulting colourless solution was cooled to 0° C. A solution of bromine (3.9 mL) in ethanoic acid (50 mL) was added dropwise over 1 h. Once the addition was complete the ice bath was removed and the resulting pale green solution was stirred overnight at room temperature. Cold water was added to the solution. The resulting white solid was collected by vacuum filteration and rinsed with water. The solid was then redissolved in EtOAc and adsorbed on silica gel. The product was purified by flash chromatography, eluting with hexane/EtOAc (4:1) to give 1 (12.5 g, 66%) as a white solid. m/z=345.98 (M+H). 1H NMR (500 MHz, CDCl3): δ: 10.43 (1H, s, CHO), 7.06 (1H, s, ArH), 6.73 (1H, s, ArH), 3.93 (3H, s, CH3O), 3.86 (3H, s, CH3O). 13C NMR (500 MHz, CDCl3): δ: 192.09 (CHO), 159.92 (C-5), 157.02 (C-3), 134.67 (C-1), 109.12 (C-2), 105.83, 103.37 (C-4 & C-6), 56.60 (OMe), 55.82 (OMe).

Provenance & Evidence