3-Bromobenzaldehyde → 5-[(3-Bromo-benzylidene)-amino]-2-fluoro-benzoic acid methyl ester

Participants

Reaction Steps

A mixture solution of 5-amino-2-fluoro-benzoic acid methyl ester (26 g, 153.8 mmol), 3-bromo-benzaldehyde (28.5 g, 153.8 mmol) and p-toluenesulfonic acid (590 mg, 3.2 mmol) in toluene (200 mL) was heated to reflux for 12 hours. Then the reaction mixture was cooled to room temperature. The solvent was removed in vacuo and the residue was washed with ether to afford 5-[(3-bromo-benzylidene)-amino]-2-fluoro-benzoic acid methyl ester (51.7 g, quant.) as a pale-white solid: MS calcd. for C15H11BrFlNO2 337.16, obsd. (ESI+) [(M+H)+] 336.0 & 338.0.

Provenance & Evidence