Bromine → 2-Bromo-3,5-dimethoxybenzaldehyde

HRID 2061339Notes

Reaction equation

[CH3:1][O:2][C:3]1[CH:4]=[C:5]([CH:8]=[C:9]([O:11][CH3:12])[CH:10]=1)[CH:6]=[O:7].[Br:13]Br>C(O)(=O)C>[Br:13][C:8]1[C:9]([O:11][CH3:12])=[CH:10][C:3]([O:2][CH3:1])=[CH:4][C:5]=1[CH:6]=[O:7]

Participants

Conditions

Temperature: 0 °C

Procedure

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).

Workup

additionOnce the addition
customwas removed
additionCold water was added to the solution
customThe resulting white solid was collected by vacuum filteration
washrinsed with water
dissolutionThe solid was then redissolved in EtOAc
customThe product was purified by flash chromatography
washeluting with hexane/EtOAc (4:1)

Sources & evidence

ORD record: ord-c1cd0e0ceb2a42089fc42064bbd22492
Source dataset: uspto-grants-2012_10
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08283340B2

Reaction notes

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