Iodine → 5-Iodo-2,4-dimethylbenzoic acid

Participants

Reaction Steps

A solution of 2,4-dimethylbenzoic acid (20.0 g, 133 mmol), sodium periodate (14.27 g, 66.72 mmol), iodine (37.25 g, 146.8 mmol), and sulfuric acid (1.96 g, 20.0 mmol) in acetic acid (150 mL) was stirred at 110° C. for 6 h. The mixture was allowed to cool to ambient temperature then carefully diluted into water (1.2 L). To this mixture was carefully added saturated aqueous Na2S2O3 (800 mL). The resulting solids were collected by filtration, then dissolved in ethyl acetate (1.2 L) and washed with saturated aqueous Na2S2O3 (300 mL) followed by brine (400 mL). The organic layer was dried (Na2SO4), filtered, and concentrated under reduced pressure. The crude residue was re-crystallized from ethanol:H2O (2:1) to yield the title compound as a white solid (30 g, 82%).

Provenance & Evidence