Synthesis of Novel Heteronanographenes via Fold-in Approach

The design of the precursor for intramolecular oxidative coupling is a key to construct novel polycyclic compounds. Fold-in type oxidative fusion reactions of heteroaromatic necklace-like molecules have been proved to be a powerful method to afford heteroatom-embedded circulenes and helicenes. The scope and limitation of this unique transformation as well as the intriguing properties of the particular products have been summarized.