Self-assembly hydrogen bonding

Osuji C, Chao CY, Bita 1, Ober CK, Thomas EL. Temperature-dependent photonic bandgap in a self-assembled hydrogen bonded liquid-crystalline block copolymer. Adv Funct Mater... 

Linear arrays of protonatable or hydrogen bonded sites may allow the directed long range transfer of protons, thus functioning as proton-conducting channel, i.e., as proton wire. Relevant systems would be linear polyamines or polyphenolic condensed aromatic units [8.218], self-assembled hydrogen bonded heterocyclic ribbons such as 116 (see Section 9.4.4) or polyelectrolyte membranes [8.219] in which collective proton motion may take place and lead to proton conductivity. 

With the exception of l,6-naphthyridin-8-ols, nuclear hdyroxy-1,6-naphthyridines would be expected to exist as the corresponding naphthyridinones. This has been confirmed by infrared,1035 ultraviolet,1026 and nuclear magnetic resonance spectral means.639 Other physicochemical studies of these oxy-1,6-naphthyridines include IR stretching frequencies1019 and ionization constants1040 of 1,6-naphthyr-idin-8-ols the mass spectra of 1,6-naphthyridinones the effect of solvents on the UV spectrum of an 8-hydroxy-1,6-naphthyridine derivative 773 and X-ray analysis of the dilactam, 4-hexyl-3,4,4a,5-tetrahydro-l,6-naphthyridine-2,7(l//,6Z/)-dione (1), in connection with its crystallization as self-assembled hydrogen-bonded polymers.549... 

The existence for such twistomers was first described by Chapman and Sherman for a self-assembled hydrogen-bonded capsule formed by the hydroxy... 

Keywords Self-assembly Hydrogen-bonding Host-guest Encapsulation Capsule... 

Table 8. Typical Linkage Modes of Self-Assembled Hydrogen-Bonded Chains and Ribbons of Urea, Thiourea or Selenourea Molecules in Their Pure Crystals and Channel Inclusion Compounds...

As mentioned above, in urea/thiourea-anion inclusion compounds both urea and thiourea molecules adopt various linkage modes not only of self-assembled hydrogen-bonded chains or ribbons but also of composite ribbons with the corresponding anions. The results show that comolecular aggregates of urea or thiourea with other neutral molecules or anionic moieties can be considered as fundamental building blocks for the constructions of various types of novel host lattices. 

Vysotsky. M.O. Thondorf. I. Bohmer, V. Self-assembled hydrogen-bonded dimeric capsules with high kinetic stability. Angew.Chem.. Int. Ed. 2008.39(7). 1264-1267. 

Keywords Liquid crystals Gelation Self-assembly Hydrogen bonding ... 

The main objective of this chapter is to review and outline the research studies and perspectives on liquid crystalline elastomers and LC anisotropic networks, with emphasis on recent interesting innovations on network-stabilized ferroelectric LC (FLC) gels, discotic columnar networks, and self-assembly hydrogen-bonded LC network. We will also present hybrid networks based on ladderlike polysiloxanes that have been developed in our group as advanced functional film materials. 

The restricted arrays of adsorbed thiols, which may be considered confined SAMs, open up a variety of possibilities as the study demonstrates a link between the self-assembled hydrogen-bonded structures discussed throughout this section and the well-estabUshed field of thiol SAMs. Buck et al. demonstrated the use of the confined adamantanethiol SAMs to guide the deposition of Cn atoms within the network pores through underpotential deposition (UPD), snch that only areas of the surface that were not covered by the network were successfully covered with Cu (Figure 9)." " A further study demonstrated that the PTCDI-melamine network acts as a diffusion barrier for Cu adatoms." The use of the hydrogen-bonded array to direct the formation of islands of Cu atoms demonstrates that the network is stable to further fabrication steps and indicates a wider applicability of such an approach to the preparation of nanostmctnres on small length scales, typically 2-5 nm. 

Brinke, G.T. and Ikkala, O. (2004) Smart materials based on self-assembled hydrogen-bonded comb-shaped supramolecules. The Chemical Record, 4,219-230. 

Figure 20. Self-assembled hydrogen bonded molecular cage of calix[6]arene tricarboxylic acid derivatives...

Reversible formation by Scheme 3.2 of a self-assembled hydrogen-bonded capsule 291 through hybridization of two nonequivalent calix[4]arene ligand syntones having carboxylic acid residues or pyridyl groups on then-upper rim is described in [2]. 

As follows from H NMR data of [14] for their cage analog 309, this self-assembled hydrogen-bonded ligand encapsulates guests shown in Scheme 3.14 in a reversible and entropy-driven process, giving rise to unusual temperature dependence of encapsulation. The positive entropy of this process is explained [14] by caging of more than one solvent molecule into the... 

Tiefenbacher K, Rebek J (2012) Selective stabilization of self-assembled hydrogen-bonded molecular capsules through - interactions. J Am Chem Soc 134(6) 2914-2917... 

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