Conjugated Nanobelts Based on N-Hetero[(6.)m8]ncyclacene

Abstract

<p><span>This study introduces a novel design of </span><i>N</i><span>-doped conjugated nanobelts, derived from a specific structural unit found in carbon schwarzites, a type of negatively curved carbon allotrope. The successful synthesis of these nanobelts was achieved using a flexible curved building block in a condensation reaction with </span><i>ortho</i><span>-quinones. The electronic structure and aromaticity of the diazatetracene-based nanobelt were investigated and compared with diazatetracene dimers through a combination of computational and experimental methods, revealing the influence of macrocyclization on these attributes. Notably, the diazatetracene-based nanobelt encapsulates C</span><span>70</span><span> in toluene with a high binding constant of (2.8 ± 0.2) × 10</span><span>5</span><span> M</span><span>−1</span><span>, demonstrating significant selectivity against C</span><span>60</span><span>. X-ray crystallographic analysis indicated that the nanobelt adjusts its rhombus cross section to enhance host–guest interactions when accommodating C</span><span>70</span><span>.</span></p>