I am dissolving 500 mg of o-phenylenediamine derivatives (4-chloro, 4-fluoro, 4-methyl, and 4-benzoyl) in 10 mL of ethanol. After complete dissolution, the solution is cooled and protected from light using aluminum foil. It is then placed in an ice–acetone bath. 1.0 ml of cold hydroiodic acid (HI, 7 M) is added dropwise under constant stirring. The initially brown-black solution gradually turns green-black. The solution is maintained at low temperature, and cold diethyl ether (20 ml) is added to induce precipitation. However, no solid precipitate forms. The goal is to isolate the iodide salt of the amine as a precursor for a subsequent synthesis.