Sulfuric Acid → 4-Iodo-3-methylbenzoic acid

Participants

Reaction Steps

20 g (0.132 mol) of 3-methyl-4-aminobenzoic acid and 175 ml of sulfuric acid (20%) were introduced into a three-necked flask. At -10° C., a solution of 11.9 g (0.172 mol) of sodium nitrite in 50 ml of water was added dropwise and the mixture was stirred for two hours. This solution was introduced dropwise via a dropping funnel cooled to -5° C. into a solution of 35 g (0.211 mol) of potassium iodide, 35.2 g (0.185 mol) of copper iodide and 175 ml of sulfuric acid (20%). The mixture was stirred for eight hours, and the reaction medium filtered. The solids obtained were dissolved in ethyl acetate, washed with water and then with a sodium sulfite solution, dried over magnesium sulfate and evaporated. 24.4 g (70%) of 3-methyl-4-iodobenzoic acid of melting point 205°-210° C. were recovered.

Provenance & Evidence