Isovanillin → 2-Bromoisovanillin

Participants

Reaction Conditions

Reaction Steps

3-Hydroxy-4-methoxy-benzaldehyde (20.0 g, 131.4 mmoles) and sodium acetate (23.7 g, 289.2 mmoles) are suspended in acetic acid (650 mL). Iron powder (513.8 mg, 9.2 mmoles) is added and the resulting suspension is cooled to approximately 15° C. A solution of bromine (23.1 g, 144.6 mmoles) in acetic acid (130 mL) is slowly (over 1 hour) dropped into the reaction mixture, keeping temperature at approximately 15° C. The reaction is left at room temperature for 30 minutes. The crude is poured in 780 mL of brine; the desired compound is filtered-off from the mother liquor and washed, sequentially, with brine and water. The product is dried under vacuum overnight to afford a white solid (26.6 g), which is used in the next step without further purification.

Provenance & Evidence