Domino Dehydrative π‐Extension: A Facile Path to Extended Perylenes and Terrylenes

Herein, we report a new method for synthesis of extended perylenes and terrylenes. The technique is based on the cascade dehydrative π‐extensions (DPEX) of aryl aldehydes, in which stepwise annulations activate previously “dormant” substituents. Two‐ and fourfold cyclizations of 3‐aryl‐biphenyl‐2,2′‐dicarbaldehydes offer a rapid path to unsymmetrical perylenes and elusive terrylene derivatives, respectively. DPEX of 3,3′′‐(phenanthrene‐1,8‐diyl)bis (([1,1′‐biphenyl]‐2,2′‐dicarbaldehyde)) leads to the biradical structure, which proceeds in situ into oxidative electrocyclization at room temperature. The described domino process complements and expands DPEX approach to a large family of fused acenes and related PAHs. Towards nanographenes: Domino‐DPEX (dehydrative π‐extension) is a new synthetic approach to extended nanographenes containing a perylene or terrylene core. The pronounced regioselctivity towards aldehyde groups in different positions makes DPEX an excellent tool for implementing pre‐programmed multiple annulation of simple precursors of elusive nanographenes. This approach enables the formation of up to five C−C bonds in one‐step in up to 94 % per C−C bond.