Constrained thermoresponsive polymers – new insights into fundamentals and applications

• Patricia Flemming,
• Alexander S. Münch,
• Andreas Fery and
• Petra Uhlmann

Beilstein J. Org. Chem. 2021, 17, 2123–2163, doi:10.3762/bjoc.17.138

• polymer chains can form superstructures that have a direct influence on the physical properties, such as mobility and intermolecular interactions, and thus also on the position and width of the phase transition. A topologically simple way to restrict the mobility of the polymer chains is the radial

Design, synthesis and application of carbazole macrocycles in anion sensors

• Alo Rüütel,
• Ville Yrjänä,
• Sandip A. Kadam,
• Indrek Saar,
• Mihkel Ilisson,
• Astrid Darnell,
• Kristjan Haav,
• Tõiv Haljasorg,
• Lauri Toom,
• Johan Bobacka and
• Ivo Leito

Beilstein J. Org. Chem. 2020, 16, 1901–1914, doi:10.3762/bjoc.16.157

• superstructures [11]. The rings should be of remarkable size for accommodating even small anions, such as acetate. In many cases the receptor is formally a macrocycle, but the anion is bound on its “surface”, not inside the ring [10][12]. A well-known example is the calix[4]pyrrole family, which emerged as an

• optimization. The chemical characteristics of the champion molecule might exclude its successful commercialization – solubility issues, chemical instability, secondary effects during binding (e.g. superstructures), too high affinity constants, insufficient selectivity towards the analyte, etc. If a champion

Nanopatterns of arylene–alkynylene squares on graphite: self-sorting and intercalation

• Tristan J. Keller,
• Joshua Bahr,
• Kristin Gratzfeld,
• Nina Schönfelder,
• Marcin A. Majewski,
• Marcin Stępień,
• Sigurd Höger and
• Stefan-S. Jester

Beilstein J. Org. Chem. 2019, 15, 1848–1855, doi:10.3762/bjoc.15.180

• each side of a specific polygon have the same length. In order to generate more complex superstructures, especially if coadsorbates will be investigated, the question will be addressed, how patterns of polygons containing side chains of different lengths within a given molecule will be formed [25]. In

Lectins of Mycobacterium tuberculosis – rarely studied proteins

• Katharina Kolbe,
• Sri Kumar Veleti,
• Norbert Reiling and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2019, 15, 1–15, doi:10.3762/bjoc.15.1

• bacteria, which is crucial for the formation of well-organized superstructures such as biofilms. In contrast to eukaryotic lectins, bacterial lectins commonly occur in the form of filamentous protein appendages projecting from their surface, known as fimbriae and pili [63]. Fimbriae are present in high

Crystal structure of the inclusion complex of cholesterol in β-cyclodextrin and molecular dynamics studies

• Elias Christoforides,
• Andreas Papaioannou and
• Kostas Bethanis

Beilstein J. Org. Chem. 2018, 14, 838–848, doi:10.3762/bjoc.14.69

• increased safety in NPC animal models [12]. Moreover, superstructures of cyclodextrins like mono-lactose-appended β-CD [13] and biocleavable pluronic/β-CD-based polyrotaxanes [14] as well as PEG-lipid micelles (DSPE-PEG) in combination with HP-β-CD [15] have shown enhanced therapeutic effects and exhibit a

Superstructures with cyclodextrins: Chemistry and applications IV

• Gerhard Wenz

Beilstein J. Org. Chem. 2017, 13, 2157–2159, doi:10.3762/bjoc.13.215

• Gerhard Wenz Saarland University, Organic Macromolecular Chemistry, Campus C4 2, 66123 Saarbrücken, Germany 10.3762/bjoc.13.215 Keywords: cyclodextrins; superstructures; Superstructures are generally formed from molecules through non-covalent interactions, which can be either attractive or

• repulsive. The first examples of superstructures formed by attractive intermolecular forces were complexes of crown ethers [1], cryptands [2] and spherands [3], which were recognized by the 1987 Nobel Prize in Chemistry. In addition, inclusion compounds of cyclodextrins (CDs), cyclic oligomers of glucose

• , belong to this category and have been known since the pioneering work of Friedrich Cramer in 1951 [4][5]. Superstructures can also be held together by repulsive forces, so-called mechanical bonds [6], as exemplified in catenanes, rotaxanes, and knots [7]. Because of their restricted mobility, rotaxanes

Superstructures with cyclodextrins: chemistry and applications III

• Gerhard Wenz and
• Eric Monflier

Beilstein J. Org. Chem. 2016, 12, 937–938, doi:10.3762/bjoc.12.91

• the group of B. J. Ravoo using host–guest interactions between polyethyleneimine grafted with β-CD and a polyamidoamine dendrimer decorated with ferrocene. The formation of the superstructures was reversible by electrochemical oxidation of the ferrocene moieties [6]. Furthermore, significant progress

Interactions between 4-thiothymidine and water-soluble cyclodextrins: Evidence for supramolecular structures in aqueous solutions

• Vito Rizzi,
• Sergio Matera,
• Paola Semeraro,
• Paola Fini and
• Pinalysa Cosma

Beilstein J. Org. Chem. 2016, 12, 549–563, doi:10.3762/bjoc.12.54

• superstructures [1][2][3]. The Nobel laureate J. M. Lehn said that “supramolecular chemistry may be defined as chemistry beyond the molecule, bearing on the organized entities of higher complexity that result from the association of two or more chemical species held together by intermolecular forces. Its

Supramolecular structures based on regioisomers of cinnamyl-α-cyclodextrins – new media for capillary separation techniques

• Gabor Benkovics,
• Ondrej Hodek,
• Martina Havlikova,
• Zuzana Bosakova,
• Pavel Coufal,
• Milo Malanga,
• Eva Fenyvesi,
• Andras Darcsi,
• Szabolcs Beni and
• Jindrich Jindrich

Beilstein J. Org. Chem. 2016, 12, 97–109, doi:10.3762/bjoc.12.11

• capillary separation techniques mainly as chiral selectors, but a common CD-based chiral selector does not form any superstructures and hence, may interact only with the analytes [4]. In comparison, the totally new type of molecular discriminators based on SPs generates superstructures (i.e., polymers

The simple production of nonsymmetric quaterpyridines through Kröhnke pyridine synthesis

• Isabelle Sasaki,
• Jean-Claude Daran and
• Gérard Commenges

Beilstein J. Org. Chem. 2015, 11, 1781–1785, doi:10.3762/bjoc.11.193

• preferred by a particular metal. These systems are of particular interest since they offer the possibility to control the assembly of helical systems to grid-like superstructures [1][4][5][6][7][8]. Depending on the metal ions, complexes with 2,2’:6’,2”:6”,2’’’-quaterpyridines as ligands can either adopt

Superstructures with cyclodextrins: Chemistry and applications II

• Gerhard Wenz

Beilstein J. Org. Chem. 2015, 11, 271–272, doi:10.3762/bjoc.11.30

Mono- and multilayers of molecular spoked carbazole wheels on graphite

• Stefan-S. Jester,
• A. Vikas Aggarwal,
• Daniel Kalle and
• Sigurd Höger

Beilstein J. Org. Chem. 2014, 10, 2783–2788, doi:10.3762/bjoc.10.295

• ]. These represent basic building blocks for a supramolecular Archimedean surface tessellation system [9]. Thereby, the highly oriented pyrolytic graphite (HOPG) acts as a template along the main axis directions of which the alkyl/alkoxy side chains align [10][11], and consequently the superstructures can

• be viewed as commensurably aligned adlayers. Among a series of characteristic superstructures, a hexagonal pattern is observed for molecular hexagons that self-assemble at the liquid/solid interface of 1,2,4-trichlorobenzene (TCB) and HOPG, however, the molecules tend to collapse (by rotation around

Self-assembled monolayers of shape-persistent macrocycles on graphite: interior design and conformational polymorphism

• Joscha Vollmeyer,
• Friederike Eberhagen,
• Sigurd Höger and
• Stefan-S. Jester

Beilstein J. Org. Chem. 2014, 10, 2774–2782, doi:10.3762/bjoc.10.294

• 2D superstructures are not predictable [17] or show a conformational polymorphism [18], also as an effect of varying compound concentrations in the supernatant solution [19][20]. A recent approach investigating macrocycles of triangular, quadratic, pentagonal, and hexagonal shapes that carry alkoxy

Lateral ordering of PTCDA on the clean and the oxygen pre-covered Cu(100) surface investigated by scanning tunneling microscopy and low energy electron diffraction

• Stefan Gärtner,
• Benjamin Fiedler,
• Oliver Bauer,
• Antonela Marele and
• Moritz M. Sokolowski

Beilstein J. Org. Chem. 2014, 10, 2055–2064, doi:10.3762/bjoc.10.213

• reported different superstructures of PTCDA on Cu(100). Schmidt et al. found a (4√2 × 5√2)R45° superstructure [8], whereas Andreasson et al. reported a (4.5 × 4.5) structure [9]. The smaller unit cell of the latter fits to the proposed loss of all O atoms. Both structures were suggested on the basis of low

• consist of two pairs of mirror domains. A structure model of one domain is shown in Figure 4(d). (We note that we have chosen the domain, which fulfills the requirements of naming superstructures defined by Barlow and Raval [17].) A symmetry equivalent domain is obtained by a mirror operation with respect

• along the and the directions, are either too large ((5√2 × 5√2)R45° /163.8 Å2 per molecule) or too small ((4√2 × 4√2)R45° /105.1 Å2 per molecule). Other quadratic commensurate superstructures on Cu(100) with a similar size to that of PTCDA/Ag(100) are rotated with respect to the former. Such a

Superstructures of fluorescent cyclodextrin via click-reaction

• Arkadius Maciollek,
• Helmut Ritter and
• Rainer Beckert

Beilstein J. Org. Chem. 2013, 9, 827–831, doi:10.3762/bjoc.9.94

• fractionation experiments coupled with a three-angle light scattering detector confirm also the formation of intermolecular superstructures (Figure 5). Structures with a molar mass of Mn up to 100,000 g/mol and also a hydrodynamic diameter up to 200 nm were detected. The conformation plot, i.e., the plot of the

Cyclodextrin-induced host–guest effects of classically prepared poly(NIPAM) bearing azo-dye end groups

• Gero Maatz,
• Arkadius Maciollek and
• Helmut Ritter

Beilstein J. Org. Chem. 2012, 8, 1929–1935, doi:10.3762/bjoc.8.224

• observed. Additionally, this azo-dye-end-group-labeled polymer was complexed with hyperbranched polyglycerol (HPG) decorated with β-CD to generate hedgehog-like superstructures. Keywords: azo-dye; cyclodextrins; end-group functionalization; host–guest interaction; supramolecular aggregation; Introduction

Superstructures with cyclodextrins: Chemistry and applications

• Helmut Ritter

Beilstein J. Org. Chem. 2012, 8, 1303–1304, doi:10.3762/bjoc.8.148

• Helmut Ritter Institute of Organic Chemistry and Macromolecular Chemistry II, Heinrich-Heine-University of Düsseldorf, Universitätsstraße 1, D-40225 Düsseldorf, Germany 10.3762/bjoc.8.148 Keywords: cyclodextrins; superstructures; Cyclodextrins (CDs) are cyclic oligosaccharides consisting of 6 (α

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

• was also demonstrated [64] (the effect of the primary grafting layer had been investigated previously for NPs coated with laterally substituted mesogens [65], see below). It was found that the superstructures of the NPs coated with ligands 71,6 and 72,5 were affected by the length of the n-alkylthiols

• bent-core ligands Bent-core mesogens display a bend in their molecular structure (Figure 18), which leads to new packing motifs and provides the possibility of forming mesophases exhibiting polar order and chiral superstructures, even in the absence of any intrinsic chirality. These interesting and

Protonation and deprotonation induced organo/hydrogelation: Bile acid derived gelators containing a basic side chain

• Uday Maitra and
• Arkajyoti Chakrabarty

Beilstein J. Org. Chem. 2011, 7, 304–309, doi:10.3762/bjoc.7.40

• properties, such as stimuli sensitivity. Their self-assembly in nanoscale superstructures are likely to have important implications in accessing functional nanomaterials [1]. The types of superstructures generated by the SAFINs (Self-Assembled Fibrillar Networks) include fibres, rods, and ribbons. Such self

Organic gelators and hydrogelators

• Jean-Pierre Desvergne

Beilstein J. Org. Chem. 2010, 6, 846–847, doi:10.3762/bjoc.6.99

• transition by heating and cooling) and, depending on the molecular structure of the gelling agent and the fluid which is rigidified, it is possible to form nanoscale superstructures such as nanofibres, nanoribbons, nanosheets, nanoparticles, helical windings, etc., which are of interest for materials and

Calix[4]arene-click-cyclodextrin and supramolecular structures with watersoluble NIPAAM-copolymers bearing adamantyl units: “Rings on ring on chain”

• Bernd Garska,
• Monir Tabatabai and
• Helmut Ritter

Beilstein J. Org. Chem. 2010, 6, 784–788, doi:10.3762/bjoc.6.83

• superstructures, CDs and calixarenes turned out to be very attractive not only as molecular receptors but also as building blocks for the construction of supramolecular architectures [5]. For that reason, we were encouraged to couple these two different types of macrocycles via click type reactions. Recent

• higher pH values, a significant change in solubility and hydrodynamic diameter was observed and correlated to the formation of superstructures. Experimental Materials. β-Cyclodextrin (β-CD) was purchased from Wacker Chemie GmbH (Burghausen, Germany) and used after drying overnight over P4O10 under an oil

Self-assembled ordered structures in thin films of HAT5 discotic liquid crystal

• Piero Morales,
• Jan Lagerwall,
• Paolo Vacca,
• Sabine Laschat and
• Giusy Scalia

Beilstein J. Org. Chem. 2010, 6, No. 51, doi:10.3762/bjoc.6.51

• and quantify the dimensions because they are closely packed together. They appear quite thick even although the section of the surface given by the AFM identifies also some thinner features, suggesting that the thick structures may be thin fibers aggregating into superstructures. As expected reducing