Synthesis
Procedure for the synthesis of 3,5-dibromo-4-methoxybenzaldehyde: To a solution of 3,5-dibromo-4-hydroxybenzaldehyde (5.00 g, 17.9 mmol) in N,N-dimethylformamide (DMF, 100 ml) was added potassium carbonate (3.22 g, 23.3 mmol) and iodomethane (1.45 ml, 23.3 mmol). The reaction mixture was stirred at room temperature for 10 hours. After completion of the reaction, the mixture was poured into water and extracted with ethyl acetate. The organic phases were combined, washed with water and dried over anhydrous magnesium sulfate. The solvent was removed by concentration under reduced pressure to give 3,5-dibromo-4-methoxybenzaldehyde as a white solid (5.10 g, yield: 97.0%). The product was characterized by 1H-NMR (CDCl3) and IR (KBr): 1H-NMR (CDCl3) δ: 3.97 (3H, s), 8.03 (2H, s), 9.80 (1H, s); IR (KBr) ν/cm-1: 1707, 1694, 1547, 1470, 1368, 1264, 1190, 987, 747, 731. 747, 731.
References
[1] Tetrahedron Letters, 2011, vol. 52, # 2, p. 212 - 214
[2] Patent: CN104672104, 2017, B. Location in patent: Paragraph 0059; 0065
[3] Patent: US2003/144338, 2003, A1
[4] Tetrahedron, 2011, vol. 67, # 49, p. 9484 - 9490
[5] Journal of Chemical Research, 2015, vol. 39, # 6, p. 336 - 339
