Oxygen- and Nitrogen-Embedded Zigzag Hydrocarbon Belts.

Despite the aesthetically appealing structures and tantalizing physical and chemical properties, zigzag hydrocarbon belts and their heteroatom-embedded analogues remain challenging synthetic targets. We report herein the synthesis of diverse O/N-doped zigzag hydrocarbon belts based on selective bridging of the fjords of resorcin[4]arene derivatives through intramolecular SN Ar and palladium-catalyzed intermolecular C-N bond formation reactions. Preorganized conformations of mono-macrocyclic, half-belt and quasi-belt compounds were revealed to facilitate cyclization reactions to construct heteroatom-linked octahydrobelt[8]arenes. The acquired products had strained square-prism-shaped belt structures in which all six-membered heterocyclic rings adopted an unusual boat conformation with equatorially configured alkyl groups. The unprecedented heteroatom-bearing belts also exhibited different photophysical and redox properties to those of octahydrobelt[8]arene analogues.

Copper-Catalyzed N,N-Diarylation of Amides for the Construction of 9,10-Dihydroacridine Structure and Applications in the Synthesis of Diverse Nitrogen-Embedded Polyacenes.

We reported herein CuI/DMEDA catalyzed N,N-diarylation reaction of amides with various di(o-bromoaryl)methanes to produce diverse 9,10-dihydroacridine derivatives. The resulting 9,10-dihydroacridine derivatives were oxidized selectively under mild conditions to afford acridine, acridinone, and acridinium derivatives. The copper-catalyzed N,N-diarylation reaction coupled with oxidative aromatization reaction enabled the facile construction of nitrogen atom-embedded tetracenes and pentacenes of different ortho-fused patterns. The luminescence properties, especially the effect of fusion pattern on fluorescence emission of acquired N-polycenes, were also demonstrated.