0000000001303522
AUTHOR
Kim Kuntze
ortho -Fluorination of azophenols increases the mesophase stability of photoresponsive hydrogen-bonded liquid crystals
Photoresponsive liquid crystals (LCs) whose alignment can be controlled with UV-Visible light are appealing for a range of photonic applications. From the perspective of exploring the interplay between the light response and the self-assembly of the molecular components, supramolecular liquid crystals are of particular interest. They allow elaborating the structure-property relationships that govern the optical performance of LC materials by subtle variation of the chemical structures of the building blocks. Herein we present a supramolecular system comprising azophenols and stilbazoles as hydrogen-bond donors and acceptors, respectively, and show that ortho-fluorination of the azophenol dr…
Photoresponsive Halogen-Bonded Liquid Crystals: The Role of Aromatic Fluorine Substitution
A new strategy for controlling the liquid crystalline and photophysical properties of supramolecular mesogens assembled via halogen bonding is reported. Changing the degree of fluorination at the halogen-bond donor of the supramolecular liquid crystal allows for the fine-tuning of the halogen bond strength and thereby provides control over the temperature range of the mesophase. At least three fluorine atoms have to be present to ensure efficient polarization of the halogen-bond donor and the formation of a mesophase. In addition, it was found that stilbazole acceptors are superior to their azopyridine counterparts in promoting stable liquid crystalline phases. The halogen-bond-driven supra…
Towards low-energy-light-driven bistable photoswitches : ortho-fluoroaminoazobenzenes
AbstractThermally stable photoswitches that are driven with low-energy light are rare, yet crucial for extending the applicability of photoresponsive molecules and materials towards, e.g., living systems. Combined ortho-fluorination and -amination couples high visible light absorptivity of o-aminoazobenzenes with the extraordinary bistability of o-fluoroazobenzenes. Herein, we report a library of easily accessible o-aminofluoroazobenzenes and establish structure–property relationships regarding spectral qualities, visible light isomerization efficiency and thermal stability of the cis-isomer with respect to the degree of o-substitution and choice of amino substituent. We rationalize the exp…
CCDC 1866422: Experimental Crystal Structure Determination
Related Article: Marco Saccone, Matthias Spengler, Michael Pfletscher, Kim Kuntze, Matti Virkki, Christoph Wölper, Robert Gehrke, Georg Jansen, Pierangelo Metrangolo, Arri Priimagi, Michael Giese|2019|Chem.Mater.|31|462|doi:10.1021/acs.chemmater.8b04197
CCDC 1866421: Experimental Crystal Structure Determination
Related Article: Marco Saccone, Matthias Spengler, Michael Pfletscher, Kim Kuntze, Matti Virkki, Christoph Wölper, Robert Gehrke, Georg Jansen, Pierangelo Metrangolo, Arri Priimagi, Michael Giese|2019|Chem.Mater.|31|462|doi:10.1021/acs.chemmater.8b04197
CCDC 1866420: Experimental Crystal Structure Determination
Related Article: Marco Saccone, Matthias Spengler, Michael Pfletscher, Kim Kuntze, Matti Virkki, Christoph Wölper, Robert Gehrke, Georg Jansen, Pierangelo Metrangolo, Arri Priimagi, Michael Giese|2019|Chem.Mater.|31|462|doi:10.1021/acs.chemmater.8b04197