Ligand-free highly effective iron/copper co-catalyzed formation of dimeric aryl ethers or sulfides

Highly selective coupling of diiodoarenes with phenols or phenthiols can be performed by using a low-cost, benign character and readily available Fe/Cu catalytic system in the absence of ligands. It is noteworthy that the desired dimeric aryl ethers or sulfides could be obtained in high yields by coupling between diiodoarenes and phenols, or diphenols with aryl iodides.