Potassium Iodide → HCID 21938638, compound

Participants

Reaction Steps

A mixture of water (405 ml) and concentrated HCl (48 ml) is stirred and cooled to 0°. 5-Ethyl-2-aminophenylacetic acid (53.7 g, 300 mmol) is slowly added while maintaining the temperature at 0–2°. After this addition a solution of sodium nitrite (22.2 g, 322 mmol) in 60 ml water is added dropwise over 30 minutes keeping the temperature at 0–2°. After a further 20 minutes a solution of potassium iodide (48 g, 290 mmol) in 18 ml conc HCl and 130 ml water is added dropwise while keeping the temperature below 10° C. The reaction mixture is allowed to warm to room temperature and then heated to reflux for 2 hours. The mixture is extracted with ethyl acetate and ether (1:1 mixture, 4×300 ml), the organic layer is then washed first with a 30% aqueous solution of sodium thiosulfite and then with a sodium hydroxide solution (0.1M) before being acidified to pH 6 and extracted with ethyl acetate. This solution is washed with saturated brine, dried (magnesium sulfate), filtered, and the solvent removed under reduced pressure. The residue is treated with hexane to yield 5-ethyl-2-iodophenylacetic acid.

Provenance & Evidence