Tetrabenz[ <i>a</i> , <i>c</i> , <i>h</i> , <i>j</i> ]anthracene-Bridged Carbaporphyrin Dimer

A new carbaporphyrin dimer (<b>8</b>) featuring a π-extended polycyclic aromatic hydrocarbon (PAH) bridge, namely, tetrabenz[<i>a</i>,<i>c</i>,<i>h</i>,<i>j</i>]anthracene (TBA), was synthesized and characterized. Single-crystal X-ray structure analysis revealed that <b>8</b> exhibits an overall nearly planar configuration. ¹H NMR spectroscopy and nucleus-independent chemical shift (NICS) calculations demonstrated reduced paratropicity in the two carbaporphyrin(1.1.1.0) subunits compared to the previously reported dibenzo[<i>g</i>,<i>p</i>]chrysene (DBC)-bridged analogue. The local aromaticity of the individual benzene rings of the TBA bridge is found to be disrupted by the fusion of the carbaporphyrin(1.1.1.0) units as well. Furthermore, <b>8</b> could coordinate with Cu(III) and Ag(III) ions to form bis-metal complexes. Metal coordination enhanced molecular planarity, and the bis-metallic complexes maintained antiaromatic characteristics. This research elucidates the regulatory role of the π extension of the PAH bridge on the (anti)aromatic character and coordination behavior of carbaporphyrin dimers, providing valuable insights for the design of novel PAH-porphyrin hybrid functional molecular systems.