Bheemireddy SR Ubaldo PC Rose PW Finke AD Zhuang J Wang L Plunkett KN 2015 A new class of stabilized pentacene derivatives with externally fused five-membered rings are prepared by means of a key palladium-catalyzed cyclopentannulation step. The target compounds are synthesized by chemical manipulation of a partially saturated 6,13-dibromopentacene precursor that can be fully aromatized in a final step through a DDQ-mediated dehydrogenation reaction (DDQ=2,3-dichloro-5,6-dicyano-1,4-benzoquinone). The new 1,2,8,9-tetraaryldicyclopenta[fg,qr]pentacene derivatives have narrow energy gaps of circa 1.2 eV and behave as strong electron acceptors with lowest unoccupied molecular orbital energies between -3.81 and -3.90 eV. Photodegradation studies reveal the new compounds are more photostable than 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene). https://sonar.ch/global/documents/13353 eng info:eu-repo/semantics/altIdentifier/doi/10.1002/anie.201508650 info:eu-repo/semantics/altIdentifier/pmid/26768696 Angewandte Chemie (International ed. in English). - 2015 acenes conjugation organic electronics palladium polycyclic aromatic hydrocarbons Stabilizing Pentacene By Cyclopentannulation. http://purl.org/coar/resource_type/c_6501