@article{FengZhouQiuetal.2022, author = {Feng, Yi and Zhou, Jiadong and Qiu, Honglin and Schnitzlein, Matthias and Hu, Jingtao and Liu, Linlin and W{\"u}rthner, Frank and Xie, Zengqi}, title = {Boron-Locked Starazine - A Soluble and Fluorescent Analogue of Starphene}, series = {Chemistry - A European Journal}, volume = {28}, journal = {Chemistry - A European Journal}, number = {29}, doi = {10.1002/chem.202200770}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-276423}, year = {2022}, abstract = {A starlike heterocyclic molecule containing an electron-deficient nonaaza-core structure and three peripheral isoquinolines locked by three tetracoordinate borons, namely isoquinoline-nona-starazine (QNSA), is synthesized by using readily available reactants through a rather straightforward approach. This new heteroatom-rich QNSA possesses a quasi-planar π-backbone structure, and bears phenyl substituents on borons which protrude on both sides of the π-backbones endowing it with good solubility in common organic solvents. Contrasting to its starphene analogue, QNSA shows intense fluorescence with a quantum yield (PLQY) of up to 62 \% in dilute solution.}, language = {en} } @article{StolteHechtXieetal.2020, author = {Stolte, Matthias and Hecht, Reinhard and Xie, Zengqi and Liu, Linlin and Kaufmann, Christina and Kudzus, Astrid and Schmidt, David and W{\"u}rthner, Frank}, title = {Crystal Engineering of 1D Exciton Systems Composed of Single- and Double-Stranded Perylene Bisimide J-Aggregates}, series = {Advanced Optical Materials}, volume = {8}, journal = {Advanced Optical Materials}, number = {18}, doi = {10.1002/adom.202000926}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218221}, year = {2020}, abstract = {Single crystals of three at bay area tetraphenoxy-substituted perylene bisimide dyes are grown by vacuum sublimation. X-ray analysis reveals the self-assembly of these highly twisted perylene bisimides (PBIs) in the solid state via imide-imide hydrogen bonding into hydrogen-bonded PBI chains. The crystallographic insights disclose that the conformation and sterical congestion imparted by the phenoxy substituents can be controlled by ortho-substituents. Accordingly, whilst sterically less demanding methyl and isopropyl substituents afford double-stranded PBI chains of complementary P and M atropo-enantiomers, single hydrogen-bonded chains of homochiral PBIs are observed for the sterically more demanding ortho-phenyl substituents. Investigation of the absorption and fluorescence properties of microcrystals and thin films of these PBIs allow for an unambiguous interpretation of these exciton systems. Thus, the J-aggregates of the double-stranded crystals exhibit a much larger (negative) exciton coupling than the single-stranded one, which in contrast has the higher solid-state fluorescence quantum yield.}, language = {en} }