Potassium Iodide → 1,4-Dibromo-2-iodobenzene

Participants

Reaction Conditions

Reaction Steps

To a stirred mixture of 2.50 g (9.96 mmol) 2,5-dibromoaniline in 7 mL conc. sulfuric acid and 20 mL water, was added a solution of 1.00 g (14.5 mmol) sodium nitrite in 10 mL water dropwise at 0° C. and the mixture was stirred at this temperature for 1.25 h. A solution of 2.15 g (13.0 mmol) potassium iodide in 20 mL water was added dropwise under ice cooling. The ice bath was removed and the reaction mixture was heated to 65° C. for 30 min. After cooling to RT, the mixture was worked up by adding aqueous sodium thiosulfate solution, followed by extraction with PE/EtOAc. The combined organic phases were washed with aqueous sodium thiosulfate solution and saturated aqueous sodium bicarbonate solution, dried over sodium sulfate, filtered and concentrated in vacuo. The crude material was purified by flash chromatography (PE/EtOAc=100→96/4).

Provenance & Evidence