P-Toluic Acid → 4-(Bromomethyl)benzoic acid

Participants

Reaction Steps

A mixture (suspension) of p-toluic acid (13.6 g, 98 mmol), N-bromosuccinimide (17.8 g, 99 mmol) and benzoylperoxide (0.2 g, 0.826 mmol) in dry benzene (100 ml) was heated at reflux for 21 h. After evaporation of the solvent in vacuo, the white residual solid was suspended in boiling water (100 ml), collected by filtration and washed with boiling water (4×100 ml). The crude dried product was crystallized from hot MeOH, yielding 15.0 g (69.7 mmol, 71.1%) of p-bromomethylbenzoic acid as white crystals mp 223°-225° C.; 1Hmr (DMSO-d6)δ: 4.75 (2H, s, --CH2Br), 7.47-7.62-7.88-8.02 ppm (4H, A2 'B2 ', aromatic Hs); ir (nujol) νmax : 2500-2600 (br.--CO2H), and 1670 cm-1 (C=O--CO2H). Procedure of D. H. Rich and S. K. Gurmura, J. Am. Chem. Soc., 97 1575 (1975).

Provenance & Evidence