The interplay of configuration and conformation in helical perylenequinones: Insights from chirality induction in liquid crystals and calculations

• Elisa Frezza,
• Silvia Pieraccini,
• Stefania Mazzini,
• Alberta Ferrarini and
• Gian Piero Spada

Beilstein J. Org. Chem. 2012, 8, 155–163, doi:10.3762/bjoc.8.16

• (Merck) nematic solvent E7 (nematic–isotropic transition temperature TNI ~ 330 K) is composed of a eutectic mixture of cyanobiphenyl and terphenyl compounds [30]. DFT calculations Atomic coordinates and energy of the conformers of 1 and 2 were obtained by geometry optimization in vacuum, by using DFT at

Imidazole as a parent π-conjugated backbone in charge-transfer chromophores

• Jiří Kulhánek and
• Filip Bureš

Beilstein J. Org. Chem. 2012, 8, 25–49, doi:10.3762/bjoc.8.4

• [77]. Terphenyl-bridged bis(benzimidazolium) salts 71, soluble in water and common organic solvents, emit blue light with λmax,em at 420–441 nm in thin films [78]. This feature makes them potentially applicable as blue-light emitters in OLEDs. Benzimidazole-based push–pull systems were studied also

Ring-alkyl connecting group effect on mesogenic properties of p-carborane derivatives and their hydrocarbon analogues

• Aleksandra Jankowiak,
• Piotr Kaszynski,
• William R. Tilford,
• Kiminori Ohta,
• Adam Januszko,
• Takashi Nagamine and
• Yasuyuki Endo

Beilstein J. Org. Chem. 2009, 5, No. 83, doi:10.3762/bjoc.5.83

• stabilization of the nematic phase, upon CH2→O replacement, was observed in p-carborane mesogens relative to benzene analogues. Thus, in series 1–4, the nematic phase is stabilized by about 14 K more for the pairs 1A/2A and 3A/4A, than for terphenyl (D) and bicyclo[2.2.2]octane (C) analogues (Figure 2

• (SmA and SmB), while the terphenyl analogues display a rich smectic polymorphism involving mainly tilted phases. The terphenyl derivatives 14D[6] and 16D[6] exhibit the most interesting polymorphism in the series with 4 smectic phases and possibly a soft crystalline modification such as a G phase below

• the SmF phase in the latter. A DSC trace for 16D[6] is shown in Figure 3, and representative textures of its mesophases are presented in Figure 4. The tilted phases in both terphenyl compounds were identified by the appearance and subsequent characteristic changes of the Schlieren textures in the