@article{oai:oist.repo.nii.ac.jp:00002585,
 author = {Xu, Xiushang and Gunasekaran, Suman and Renken, Scott and Ripani, Lorenzo and Schollmeyer, Dieter and Kim, Woojae and Marcaccio, Massimo and Musser, Andrew and Narita, Akimitsu},
 journal = {Advanced Science},
 month = {Feb},
 note = {Exploration of novel biaryls consisting of two polycyclic aromatic hydrocarbon (PAH) units can be an important strategy toward further developments of organic materials with unique properties. In this study, 5,5′-bibenzo[rst]pentaphene (BBPP) with two benzo[rst]pentaphene (BPP) units is synthesized in an efficient and versatile approach, and its structure is unambiguously elucidated by X-ray crystallography. BBPP exhibits axial chirality, and the (M)- and (P)-enantiomers are resolved by chiral high-performance liquid chromatography and studied by circular dichroism spectroscopy. These enantiomers have a relatively high isomerization barrier of 43.6 kcal mol⁻¹ calculated by density functional theory. The monomer BPP and dimer BBPP are characterized by UV-vis absorption and fluorescence spectroscopy, cyclic voltammetry, and femtosecond transient absorption spectroscopy. The results indicate that both BPP and BBPP fluoresce from a formally dark S₁ electronic state that is enabled by Herzberg–Teller intensity borrowing from a neighboring bright S₂ state. While BPP exhibits a relatively low photoluminescence quantum yield (PLQY), BBPP exhibits a significantly enhanced PLQY due to a greater S₂ intensity borrowing. Moreover, symmetry-breaking charge transfer in BBPP is demonstrated by spectroscopic investigations in solvents of different polarity. This suggests high potential for singlet fission in such π-extended biaryls through appropriate molecular design.},
 title = {Synthesis and Characterizations of 5,5′‐Bibenzo[rst]pentaphene with Axial Chirality and Symmetry‐Breaking Charge Transfer},
 year = {2022}
}