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

Participants

Reaction Steps

2,5-Dibromoaniline 10 g was dispersed in diluted hydrochloric acid (concentrated hydrochloric acid 40 ml+water 30 ml), and an aqueous solution of NaNO2 3 g was dropwise added thereto at 0° C. The reaction solution was stirred for 40 minutes and then dropwise added at room temperature to an aqueous solution of potassium iodide 60 g which was separately prepared. After stirring at room temperature for 2 hours, methylene chloride and a small amount of sodium hydrogensulfite were added thereto, and the organic layer was extracted. The organic layer was washed with a 10% sodium hydrogensulfite aqueous solution and saturated brine and dried on anhydrous sodium sulfate, and then the solvent was distilled off. The product was refined by silica gel chromatography, whereby targeted 2,5-dibromoiodobenzene 10.5 g (yield: 73%) was obtained in the form of white crystal.

Provenance & Evidence