Corannulene ethers via Ullmann condensation.

Penta-aryloxycorannulene derivatives, which were previously considered difficult synthetic targets, are efficiently achieved via the Cu(I)-catalyzed Ullmann condensation reaction between 1,3,5,7,9-pentachlorocorannulene and a broad variety of substituted phenols. The reaction proceeds under air and mild conditions that are compatible even with 4-bromophenol. These findings open new avenues for easy preparation of other symmetrically substituted pentagonal building blocks that can be used for the preparation of new materials and new supramolecular architectures.