o-Toluic Acid

2-Methylbenzoic acid (o-toluic acid) forms white prismatic or needle-like crystals, widely used in pharmaceutical, agrochemical, dye and plasticizer synthesis. Melting point 103-105 °C; soluble in ethanol, ether and chloroform, slightly soluble in water; purity above 99.0%.

The carboxyl group undergoes salt formation, esterification, acyl chlorination, amidation and reduction; the benzylic hydrogens of the ortho methyl are relatively reactive and can be halogenated or oxidized to give phthalic-acid-type derivatives; the ortho substituent also influences reaction selectivity through hydrogen bonding or steric effects.