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Abstract: The synthesis and characterization of novel macrocyclic, phenylene‐bridged azaacenes is reported. These species were obtained either by a conventional benzoin– diamine condensation, as shown for the case of the cyclotrimers, in which the azaacene units are separated by meta‐connected phenylene bridges, or by a Buchwald–Hartwig‐type Pd‐catalyzed coupling, which employs 1,2,5,6‐tetrabromodibenzocyclooctatetraene as the substrate and bis‐TIPS‐ethynylated diaminobenzene, ‐naphthalene or ‐anthracene as the coupling partner to give the double coupling products azaacene‐annulated dibenzocyclooctatetraenes in moderate yields. The macrocycles show strong emission and light emitting diodes have been built with brightnesses exceeding 1600 cd m−2. We evaluated the optical and electronic properties and the solid‐state structures of the molecules and discuss their properties through comparison with their linear and tetrameric N‐heteroacene counterparts. [ABSTRACT FROM AUTHOR]

We describe the modular synthesis and characterization of several substituted N-hetero benzenacyclooctaphanes (BAOs), a new motif for heteroaromatic conjugated macrocycles. The targets were synthesized via condensation of substituted aromatic ortho-diamines with a cyclic octaketone building block in moderate to excellent yields (41-91 %). We evaluated the optical and electronic properties and the solid-state structures of the targets and discuss their properties through comparison with their linear diphenyl N-heteroacene counterparts. [ABSTRACT FROM AUTHOR]

Using cyanide-assisted benzoin condensation of isophthaldehyde, we prepared cyclotribenzoin: a cone-shaped macrocycle whose three benzene rings define a cuplike cavity, while six of its C–H bonds convergently point in the opposite direction. This combination of convergently oriented cation- and anion-binding groups, coupled with an exceedingly simple synthesis, promises to make cyclotribenzoin an appealing platform for supramolecular chemistry studies. [ABSTRACT FROM AUTHOR]

Interstellar! The modular synthesis and characterization of several substituted N ‐ hetero benzenacyclooctaphanes, a new motif for heteroaromatic conjugated cycles, is presented. The graphic illustrates the versatility of our system, demonstrated by several crystal structures of our target molecules. These were synthesized by condensation of substituted aromatic ortho ‐ diamines with a cyclic octaketone building block. More information can be found in the Full Paper by U. H. F. Bunz et al. on page 10543. [ABSTRACT FROM AUTHOR]