Supramolecular architecture of metal-lustrous inclusion crystals based on aromatic CH–π interaction: versatile inclusion of 1-(p-ethoxyphenyl)-2-(2-thienyl)-5-[5-(tricyanoethenyl)-2-thienyl]pyrrole host with various electron-rich aromatic guest molecules

1-(p-Ethoxyphenyl)-2-(2-thienyl)-5-[5-(tricyanoethenyl)-2-thienyl]pyrrole, a novel π-conjugated organic compound, shows particularly stronger affinities to various electron-rich aromatic guest molecules to form 2:1 inclusion complexes with gold- or bronze-like metallic luster. All of the complexes crystallize with the same so-called herringbone packing motif in which the π-system of the guest is sandwiched diagonally between the host molecules around it. The unique aromatic CH–π interactions between the host and the guest molecules essentially ascribe to the architecture of these complexes. The sidewise intermolecular π–π contacts (CN⋯CC) between the host molecules deeply affect the crystal appearance.