Liquid-crystalline heterodimesogens and ABA-heterotrimesogens comprising a bent 3,5-diphenyl-1,2,4-oxadiazole central unit

• Govindaswamy Shanker,
• Marko Prehm and
• Carsten Tschierske

Beilstein J. Org. Chem. 2012, 8, 472–485, doi:10.3762/bjoc.8.54

• comparable to the molecular length Lmol = 4.5–4.6 nm in the most stretched conformation (determined with CPK models). This indicates a kind of monolayer organization of the molecules in the cybotactic clusters. In the SmA-like clusters the alkyl chains are segregated from the aromatic cores, and the

• ). Considering the tilt, a calculated d-value of dcal = 4.8 nm would be expected according to dcal = Lmol cos β for the molecule in the most stretched conformation and a reduction to the experimental value of d = 4.4 nm is easily possible by conformational disorder. Hence, it is in line with a monolayer

• with the C5 spacers are organized side-by-side and separated from the alkyl chains in the monolayer smectic phases and in the cybotactic clusters of the nematic phase (Figure 4a), in the case of compound Thia-Ox/10 the longer C10 spacers cannot be accommodated between the aromatic cores. These long

Liquid-crystalline nanoparticles: Hybrid design and mesophase structures

• Gareth L. Nealon,
• Romain Greget,
• Cristina Dominguez,
• Zsuzsanna T. Nagy,
• Daniel Guillon,
• Jean-Louis Gallani and
• Bertrand Donnio

Beilstein J. Org. Chem. 2012, 8, 349–370, doi:10.3762/bjoc.8.39

• hexagonal lattices has been observed for simple monolayer-protected NPs on surfaces [52]. Whilst theoretical treatments predict that Au NPs coated with simple linear thiols should exhibit spontaneous asymmetry at low temperatures or in solution [53][54][55], simple NP-hybrids of this type are yet to exhibit

• ), respectively, in a two-step process to give a 1:1 mixed monolayer coverage [76]. Bent-core ligand 1410,10 displayed a monotropic LC phase whilst 1412,11 was not mesomorphic. Unfortunately, the hybrids did not display any LC phases, though they could be dispersed into some selected bent-core LC hosts, which

Fifty years of oxacalix[3]arenes: A review

• Kevin Cottet,
• Paula M. Marcos and
• Peter J. Cragg

Beilstein J. Org. Chem. 2012, 8, 201–226, doi:10.3762/bjoc.8.22

• cationic complex was deposited as a monolayer onto an alkylsulfonate coated gold surface and elicited both a redox response, as determined by cyclic voltammetry, and a photochemical response to visible light [83][84]. The optical response was studied further [85], and a transient band was observed at 545

Syntheses and properties of thienyl-substituted dithienophenazines

• Annemarie Meyer,
• Eva Sigmund,
• Friedhelm Luppertz,
• Gregor Schnakenburg,
• Immanuel Gadaczek,
• Thomas Bredow,
• Stefan-S. Jester and
• Sigurd Höger

Beilstein J. Org. Chem. 2010, 6, 1180–1187, doi:10.3762/bjoc.6.135

• -condensed thiophene analogues. These assignments of the thiophene moieties as donors and the phenazine moieties as acceptors are confirmed by quantum-chemical calculations at the density-functional level. Additionally, one of the compounds forms a self-assembled monolayer on a HOPG surface, as imaged by

• of a self-assembled monolayer, most probably due to sterical hindrance of the molecules to cover the surface densely. Conclusion We have developed a simple method for preparing phenazine-thiophene oligomers. These compounds show interesting optical characteristics, which can be tuned by attachment of

• transition to this state. Self-assembled monolayer of 12b on HOPG. a) STM image (VS = −0.8 V, It = 80 pA, image size 25.0 × 25.0 nm2); b) structure model [39]. Synthesis of 4. a) 1) EtLi, Et2O, −78 °C, 1 h; 2) (COOMe)2, Et2O, −78 °C, 2 h, 33%; b) FeCl3, MeNO2, CH2Cl2, rt, 16 h, 71%; c) Br2, AcOH, CHCl3

Synthesis, electronic properties and self-assembly on Au{111} of thiolated (oligo)phenothiazines

• Adam W. Franz,
• Svetlana Stoycheva,
• Michael Himmelhaus and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2010, 6, No. 72, doi:10.3762/bjoc.6.72

• presence of a gold-coated silicon wafer. Monolayer formation is confirmed by ellipsometry and the results compared to those obtained by force field and DFT calculations. Keywords: cyclic voltammetry; ellipsometry; phenothiazines; SAM; thiols; Introduction Functional organic π-systems [1] are of great

• influenced by the adjacent phenyl system. Table 2 shows dth for the different molecules along with the experimental thickness dexp as determined by ellipsometry. The theoretical thicknesses are given for MM2 as well as DFT calculations. As a simple measure of monolayer formation of the different systems, the

Molecular recognition of organic ammonium ions in solution using synthetic receptors

• Andreas Späth and
• Burkhard König

Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32

Versatile supramolecular reactivity of zinc-tetra(4-pyridyl)porphyrin in crystalline solids: Polymeric grids with zinc dichloride and hydrogen-bonded networks with mellitic acid

• Sophia Lipstman and
• Israel Goldberg

Beilstein J. Org. Chem. 2009, 5, No. 77, doi:10.3762/bjoc.5.77

• further significance to studies of surface-based crystallizations of monolayer and multilayer hydrogen-bonded networks and metal–organic frameworks on various substrates [26][27], in the context of the design of novel molecular devices. Experimental The ZnTPyP, 1,4,5,8-naphthalenetetracarboxylic acid

Stereoselective synthesis of (2S,3S,4Z)-4-fluoro- 1,3-dihydroxy- 2-(octadecanoylamino)octadec- 4-ene, [(Z)-4-fluoroceramide], and its phase behavior at the air/water interface

• Gergana S. Nikolova and
• Günter Haufe

Beilstein J. Org. Chem. 2008, 4, No. 12, doi:10.3762/bjoc.4.12

• to stronger intermolecular interactions between the hydrophobic chains of neighboring molecules, and therefore to increasing stability of the monolayer of 4-fluoroceramide at the air water interface. Introduction Sphingolipids belong to the most important constituents of the membranes of eukaryotic

• -fluorinated parent compounds, and therefore to higher stability of the monolayer formed at the air/water interface. This unique behavior of the 4-fluoroceramide molecules provides the basis for further development of the morphology of the monolayer and possible formation of multi-layers, as well as for