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Superb control over the helical chirality of highly-entangled (M3L2)n polyhedra (M = Cu(i), Ag(i); n = 2,4,8) was achieved via multiplication of weak chiral inductions by side chains accumulated on the huge polyhedral surfaces.

Discrete (M3L2) n cages assembled from a tripodal ligand (L) and metal ions (M: Cu(i) or Ag(i)) are embedded in networked coordination hosts formed by partial dissociation of the same discrete cages during the crystallization process. The resulting "eggs-in-an-egg-carton" structures provide unique examples of the co-crystallization of discrete and infinite coordination frameworks.

The cooperation of weak acetylene π-coordination and relatively strong metal-heteroatom coordination has emerged as a promising strategy for the construction of highly complex but well-ordered nanostructures. Here, we report the formation of an (M

A microgram-scale X-ray structure analysis of small molecules was developed by applying a modern high-throughput crystallization technique to classical co-crystallization via acid-base salt formation. The use of an automatic dispensing machine for the crystallization screening reduces the required amount of sample to the microgram scale. Absolute configurations of a chiral alkaloid and three chiral pharmaceutical acids were obtained by X-ray crystallography from 210–530 µg of samples by this renovated method.

Flexible chain-like molecules can adopt various conformations, but fabrication of complex and higher-order architectures by chain networking or coiling is still a difficult task in organic chemistry. As the degree of freedom increases, the large entropy loss impedes conformation and orientation fixing. Here we report oligo (3,3-dimethylpentane-2,4-dione)s as flexible and shapable carbon chains with many carbonyl groups for chemical modification. Polycarbonylated chains of various lengths are synthesized by terminal-selective silylation and oxidative coupling reactions using silver(I) oxide. We use reactions of 1,3-diketones and 1,4-diketones to reduce the chain length and to induce favourable conformations. When the chains are treated with hydrazine, all the carbonyl groups are converted to imine groups, resulting in the formation of multidentate ligands. Finally, a two-dimensional sheet-like structure and a cylindrical assembly are generated by respectively networking and coiling the carbon chains, with the aid of metal coordination.

A dendritic unit based on a benzenetricarboxamide core and three triarylamine arms has been synthesized and characterized. Self-assembled micrometric crystalline fibers can be formed in various organic solvents. This derivative has also been studied in chlorinated solvents upon visible light stimulation, giving rise to self-assembled fibers with triarylammonium cations trapped in their supramolecular structure. Overall, this work enlarges the scope of chemical modifications that can be made on triarylamine cores to produce doped supramolecular architectures with potential interests for optoelectronic materials.

We have synthesized a series of triarylamine-cored molecules equipped with an adjacent amide moiety and dendritic peripheral tails in a variety of modes. We show by (1) H NMR and UV/Vis spectroscopy that their supramolecular self-assembly can be promoted in solution upon light stimulation and radical initiation. In addition, we have probed their molecular arrangements and mesomorphic properties in the bulk by integrated studies on their film state by using differential scanning calorimetry (DSC), variable-temperature polarizing optical microscopy (VT-POM), variable-temperature X-ray diffraction (VT-XRD), and atomic force microscopy (AFM). Differences in the number and the disposition of the peripheral tails significantly affect their mesomorphic properties associated with their lamellar- or columnar-packed nanostructures, which are based on segregated stacks of the triphenylamine cores and the lipophilic/lipophobic periphery. Such structural tuning is of interest for implementation of these soft self-assemblies as electroactive materials from solution to mesophases.

The conclusion is inevitable: Increasing stabilization of an anionic transition state with increasing p acidity of the catalyst is observed; thus anion p interactions can contribute to catalysis. © 2013 WILEY VCH Verlag GmbH Co. KGaA Weinheim.

Reactions of a neutral pentacoordinated monohydrosilane bearing a dative N‒Si bond with phenol and benzoic acid derivatives gave the corresponding pentacoordinated phenoxysilane and carboxysilanes, respectively. X-ray crystallographic analyses of these silanes revealed that the distance of the N‒Si dative bond is shortened and the pentacoordination character of the silicon center becomes greater with the increase in the electron-withdrawing character of the apical substituent on silicon.

A pentacoordinated hydrosilane activated by an intramolecular nitrogen-silicon dative bond was utilized as an end-capping agent for catalyst-free syntheses of [2]rotaxanes. The end-capping reaction of a pseudo[2]rotaxane bearing a salicylic acid terminus with the pentacoordinated hydrosilane readily proceeded at room temperature to produce the corresponding silyl-capped [2]rotaxane.

Efficient end-capping synthesis of neutral donor-acceptor (D-A) [2]rotaxanes without loading any catalysts or activating agents was achieved by utilizing high reactivity of a pentacoordinated hydrosilane toward salicylic acid derivatives. As components of [2]rotaxanes, an electron-deficient naphthalenediimide-containing axle with a salicylic acid terminus and several electron-rich bis(naphthocrown) ether macrocycles were employed. End-capping reactions with the pentacoordinated hydrosilane underwent smoothly even at low temperature to afford the corresponding [2]rotaxanes in good yields. A [2]rotaxane containing bis-1,5-(dinaphtho)-38-crown-10 ether as a wheel molecule was synthesized and isolated in 84% yield by the end-capping at -10 °C, presenting the highest yield ever reported for the end-capping synthesis of a neutral D-A [2]rotaxane. It was found that the yields of the [2]rotaxanes in the end-capping reactions were almost parallel to the formation ratios of the corresponding pseudo[2]rotaxanes estimated by utilizing model systems. These results indicate that the end-capping reaction using the pentacoordinated hydrosilane proceeded without perturbing the threading process, and most of the pseudo[2]rotaxanes underwent efficient end-capping reaction even at low temperature.

The introduction of new noncovalent interactions to build functional systems is of fundamental importance. We here report experimental and theoretical evidence that anion-π interactions can contribute to catalysis. The Kemp elimination is used as a classical tool to discover conceptually innovative catalysts for reactions with anionic transition states. For anion-π catalysis, a carboxylate base and a solubilizer are covalently attached to the π-acidic surface of naphthalenediimides. On these π-acidic surfaces, transition-state stabilizations up to ΔΔGTS = 31.8 ± 0.4 kJ mol(-1) are found. This value corresponds to a transition-state recognition of KTS = 2.7 ± 0.5 μM and a catalytic proficiency of 3.8 × 10(5) M(-1). Significantly increasing transition-state stabilization with increasing π-acidity of the catalyst, observed for two separate series, demonstrates the existence of "anion-π catalysis." In sharp contrast, increasing π-acidity of the best naphthalenediimide catalysts does not influence the more than 12 000-times weaker substrate recognition (KM = 34.5 ± 1.6 μM). Together with the disappearance of Michaelis-Menten kinetics on the expanded π-surfaces of perylenediimides, this finding supports that contributions from π-π interactions are not very important for anion-π catalysis. The linker between the π-acidic surface and the carboxylate base strongly influences activity. Insufficient length and flexibility cause incompatibility with saturation kinetics. Moreover, preorganizing linkers do not improve catalysis much, suggesting that the ideal positioning of the carboxylate base on the π-acidic surface is achieved by intramolecular anion-π interactions rather than by an optimized structure of the linker. Computational simulations are in excellent agreement with experimental results. They confirm, inter alia, that the stabilization of the anionic transition states (but not the neutral ground states) increases with the π-acidity of the catalysts, i.e., the existence of anion-π catalysis. Preliminary results on the general significance of anion-π catalysis beyond the Kemp elimination are briefly discussed.

Bring it on: Organic chemistry on surfaces and in solution is not the same; this study offers a perfect example that small changes (from 27 to 35°; see graphic) can result in big consequences. Strained cyclic disulfides from asparagusic but not lipoic acid are ideal for growing functional architectures directly on surfaces; for the substrate initiated synthesis of cell penetrating poly(disulfide)s in solution exactly the contrary is true. Copyright © 2013 WILEY VCH Verlag GmbH Co. KGaA Weinheim.

A triarylmethane-based host molecule with three anthryl groups that can interact with C60 was synthesized. Co-recrystallization of this host molecule with C(60) resulted in a linear alignment of C60 in the hexagonal columnar space formed by intra- and intermolecular CH...pi interactions between anthryl groups in the crystalline state.

A fluorescent host molecule bearing a bicyclic triarylphosphate framework was synthesized. Its inclusion behavior to C60 was revealed by fluorescent titration. Cocrystallization of the host and C60...

In nature spectacular function is achieved by highly sophisticated supramolecular architectures. Little is known what we would obtain if we could create complexity with similar precision because the synthetic methods to do so are not available. This account summarizes recent approaches conceived to improve on this situation. With self organizing surface initiated polymerization (SOSIP) charge transporting stacks can be grown directly on solid substrates with molecular level precision. The extension to templated self sorting (SOSIP TSS) offers a supramolecular approach to multicomponent architectures. A solid theoretical framework for the transcription of information by templated self sorting has been introduced intrinsic templation efficiencies up to 97 have been achieved and the existence of self repair has been shown. The extension to templated stack exchange (SOSIP TSE) offers the complementary covalent approach. Compatibility of this robust method with the creation of double channel architectures with antiparallel two component gradients has been demonstrated. © 2013 The Royal Society of Chemistry.

Metallic nanostructures are able to interact with an incident electromagnetic field at subwavelength scales by plasmon resonance which involves the collective oscillation of conduction electrons localized at their surfaces. Among several possible applications of this phenomenon, the theoretical prediction is that optical circuits connecting multiple plasmonic elements will surpass classical electronic circuits at nanoscale because of their much faster light-based information processing. However, the placement and coupling of metallic elements smaller than optical wavelengths currently remain a formidable challenge by top-down manipulations. Here, we show that organic supramolecular triarylamine nanowires of ≈1 nm in diameter are able to act as plasmonic waveguides. Their self-assembly into plasmonic interconnects between arrays of gold nanoparticles leads to the bottom-up construction of basic optical nanocircuits. When the resonance modes of these metallic nanoparticles are coupled through the organic nanowires, the optical conductivity of the plasmonic layer dramatically increases from 259 to 4271 Ω(-1)·cm(-1). We explain this effect by the coupling of a hot electron/hole pair in the nanoparticle antenna with the half-filled polaronic band of the organic nanowire. We also demonstrate that the whole hybrid system can be described by using the abstraction of the lumped circuit theory, with a far field optical response which depends on the number of interconnects. Overall, our supramolecular bottom-up approach opens the possibility to implement processable, soft, and low cost organic plasmonic interconnects into a large number of applications going from sensing to metamaterials and information technologies.