Triphenanthro‐anellierte [18]Annulene mit Alkoxy‐Seitenketten — Eine neue Klasse discotischer Flüssigkristalle

1994

Triphenanthro-Anellated [18]Annulenes with Alkoxy Side Chains - A Novel Class of Discotic Liquid Crystals Two different types 6 and 16 of [18]annulenes condensed with phenanthrene systems were prepared by cyclocondensation reactions (Schemes 2 and 3). The central 18-membered rings do not show a macrocyclic diamagnetic ring current. Conformational analyses and X-ray analyses in the solid state reveal non-planar structures in which aromatic “islands” are connected by (E)-configurated olefinic bridges. The introduction of long alkoxy side chains yields a new class of discotic liquid crystals; either ND or hexagonal columnar phases are generated, which were characterized by DSC, microscopy with…

The 2016 EU Referendum Stories in Austrian, German, and Swiss Media: Catastrophes, Characterizations, Challenges

2018

People construct meaning by telling stories, so what are the stories told in Austrian, German and Swiss media about the 2016 EU referendum? They are stories of catastrophe and tragedy; of politicians characterized as working for their parties and careers, not for the public; stories of right-wing populism and nationalism, constructing illusions about the nation’s history; descriptions of responsibilities and the enormous causes and consequences of the EU referendum; stories of the incredible threats to society, democracy and the state; and definitions of what needs to be done now in the EU and UK in order to improve people’s lives.

(Z)- und (E)-Enole von diarylsubstituierten β-Ketocarbonsäurederivativen

2006

(Z) and (E) Enols of Diaryl-Substituted β-Ketocarboxylic Acid Derivatives Thermolysis of the 1,3-diaryl-2-diazo-1,3-propanediones 4 in the presence of alcohols or amines yielded the compounds 7–11 which exist as chelated (Z) enols or as tautomeric ketones. Contrary to the steric interaction of two mesityl groups the steric interaction between two naphthyl or two anthryl groups or between naphthyl and mesityl is not sufficient to stabilize the corresponding (E) enols. The latter isomers were generated in irradiation processes of some (Z) enols. Detailed NMR studies were performed in order to characterize the enols and their molecular dynamics.

Kommentierte Hilfs- und Arbeitsmittel

2004

Bibliographie der zitierten Literatur

2004

Einleitung: Das Netzwerk der englischsprachigen Kulturen und der Anglistik

2004

Die Gebiete, in denen das Englische heute als Erst- oder Zweitsprache gesprochen wird, werden u.a. mit dem Begriff ›Terranglia‹ zusammengefasst.

Selectivity in the direction of photoisomerization reactions in liquid-crystalline guest-host systems

1995

E ⇄ Z photoisomerization reactions of stilbenes la-c were studied in liquid-crystalline (LC) phases and in the corresponding isotropic melts. Whereas viscosity has a moderate influence on the photostationary states, a strong effect caused by the regular incorporation of the stilbene molecules in the LC phases was observed. The direction of the isomerization can be reversed, up to the case of a one-way isomerization Z E for the tailored guest-host system 1b/BS. Such an LC-matrix effect is of typical highly ordered (smectic) phases with free volumina which are strictly limited by hydrophobic interactions; it could not be detected in a much more mobile nematic phase. Textures based on the bire…