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The functionalization of polycyclic aromatic hydrocarbons (PAHs) via B←N Lewis pair formation offers an opportunity to judiciously fine‐tune the structural features and optoelectronic properties, to suit the demands of applications in organic electronic devices, bioimaging, and as sensitizers for singlet oxygen generation. We demonstrate that the N‐directed electrophilic borylation of 2,6‐di(pyrid‐2‐yl)anthracene offers access to linearly extended acene derivativesPy‐BR(R=Et, Ph, C₆F₅). In comparison to indeno‐fused 9,10‐diphenylanthracene, the formal “BN for CC” replacement inPy‐BRselectively lowers the LUMO, resulting in a much reduced HOMO–LUMO gap. An even more extended conjugated system with seven six‐membered rings in a row (Qu‐BEt) is obtained by borylation of 2,6‐di(quinolin‐8‐yl)anthracene. FluorinatedPy‐BPfshows particularly advantageous properties, including relatively lower‐lying HOMO and LUMO levels, strong yellow‐green fluorescence, and effective singlet oxygen sensitization, while resisting self‐sensitized conversion to its endoperoxide.

The functionalization of polycyclic aromatic hydrocarbons (PAHs) via B←N Lewis pair formation offers an opportunity to judiciously fine‐tune the structural features and optoelectronic properties, to suit the demands of applications in organic electronic devices, bioimaging, and as sensitizers for singlet oxygen generation. We demonstrate that the N‐directed electrophilic borylation of 2,6‐di(pyrid‐2‐yl)anthracene offers access to linearly extended acene derivativesPy‐BR(R=Et, Ph, C₆F₅). In comparison to indeno‐fused 9,10‐diphenylanthracene, the formal “BN for CC” replacement inPy‐BRselectively lowers the LUMO, resulting in a much reduced HOMO–LUMO gap. An even more extended conjugated system with seven six‐membered rings in a row (Qu‐BEt) is obtained by borylation of 2,6‐di(quinolin‐8‐yl)anthracene. FluorinatedPy‐BPfshows particularly advantageous properties, including relatively lower‐lying HOMO and LUMO levels, strong yellow‐green fluorescence, and effective singlet oxygen sensitization, while resisting self‐sensitized conversion to its endoperoxide.