TY  - JOUR
A1  - Feng, Yi
A1  - Zhou, Jiadong
A1  - Qiu, Honglin
A1  - Schnitzlein, Matthias
A1  - Hu, Jingtao
A1  - Liu, Linlin
A1  - Würthner, Frank
A1  - Xie, Zengqi
T1  - Boron‐Locked Starazine – A Soluble and Fluorescent Analogue of Starphene
JF  - Chemistry – A European Journal
N2  - 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.
KW  - conjugated molecule
KW  - electronic structure
KW  - luminescence
KW  - starazine
KW  - starphene analogue
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-276423
VL  - 28
IS  - 29
ER  - 
TY  - JOUR
A1  - Stolte, Matthias
A1  - Hecht, Reinhard
A1  - Xie, Zengqi
A1  - Liu, Linlin
A1  - Kaufmann, Christina
A1  - Kudzus, Astrid
A1  - Schmidt, David
A1  - Würthner, Frank
T1  - Crystal Engineering of 1D Exciton Systems Composed of Single‐ and Double‐Stranded Perylene Bisimide J‐Aggregates
JF  - Advanced Optical Materials
N2  - 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.
KW  - fluorescence
KW  - J‐aggregates
KW  - perylene bisimides
KW  - reabsorption
KW  - single crystal structure
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218221
VL  - 8
IS  - 18
ER  -