Bis(tetraarylcyclopentadienones) (BTACPDs) are key monomers used for preparing aromatic polymers and, in particular, aryl-substituted polyphenylenes (ASPPs) via the Diels–Alder reaction [1]. ASPPs are unique polymers that combine the aromaticity of mac- romolecules with a high molecular weight and high sol- ubility in organic solvents. Most ASPPs contain only carbocyclic fragments, whereas the introduction of het- erocycles, such as thiophene, ...