Hydrogen-bonded supramolecular

Coco, S., Cordobilla, C., Dominguez, C. and Espinet, P. (2008) Luminescent gold(I) metallo-adds and their hydrogen bonded supramolecular liquid crystalline derivative s with decyloxystilbazole as hydrogen acceptor. Dalton Transactions, 48,6894—6900. 

Hydrogen-Bonded Supramolecular Chain and Sheet Formation by Coordinated Guanidine Derivatives... 

Hubberstey P, Suksangpanya U (2004) Hydrogen-Bonded Supramolecular Chain and Sheet Formation by Coordinated Guranidine Derivatives 111 33-83 Hupp JT (2006) Rhenium-Linked Multiporphyrin Assemblies Synthesis and Properties 121 145-165... 

Keywords Hydrogen bonding Supramolecular chains Supramolecular sheets Coordination Guanidine... 

Supramolecular architectures in which transition metal cationic centres are linked via hydrogen-bonded supramolecular synthons [1,2] comprise an increasingly important class of inorganic co-ordination polymers [3], owing to their multi-dimensional, multi-functional network structures. 

Lange RFM, van Gurp M, Meijer EW. Hydrogen-bonded supramolecular polymer networks. J Polym Sci Part A Polym Chem 1999 37 3657-3670. 

Armstrong G, Buggy M. Hydrogen-bonded supramolecular polymers a Uterature review. J Mater Sci 2005 40 547-559. 

Shimizu LS. Perspectives on main-chain hydrogen bonded supramolecular polymers. Polym... 

Figure 17 The hydrogen-bonded supramolecular synthon present in all helical tubulate inclusion compounds formed by diol 11 (and its family of hosts). The molecules hydrogen bond together O-H O-H O-H to form the threefold screw axis structure illustrated. Identical arrangements subtended by the second diol hydroxy groups give rise to the chiral tubular lattice structure shown in Figure 16. Hydrogen atoms are omitted for clarity.

Figure 18 The hydrogen-bonded supramolecular synthon present in the helical tubulate compound (12)2-(13)-(toluene). Hydrogen atoms are omitted for clarity.

The self-assembling cyclic D,L-cc-peptide nanotubes described demonstrate high stability on surfaces even after two months exposure to ambient temperature. NDI peptide nanotubes 18 may provide a facile method for the preparation of a new class of synthetic biomaterials [16b, 34a]. Recently Sanders and co-workers demonstrated the formation of amino acid-derived NDI hydrogen-bonded supramo-lecular organic M-helical nanotubes in nonpolar solvents and also in the solid state [34b]. The hydrogen-bonded supramolecular nature of the helical nanotubes was confirmed by the circular dichroism (CD) spectrum in chloroform with the addition of methanol, destruction of the supramolecular nanotubes was observed, due to the capabilities of such an aprotic solvent to compete for hydrogen-bond interactions [34b]. 

New crosslinked elastomers may be formed by self-aggregation of substituted functional units able to form directed hydrogen-bonds. 1,4-PB has been randomly substituted with about 4 mol% urazole units [94], The urazole units form hydrogen-bonded supramolecular, plate-like aggregates which act as effective crosslinking zones, thus creating a thermoplastic elastomer [95, 96, 97]. The system is deuterated either in the PB backbone or in the urazole units, which allows to investigate the molecular dynamics in... 

Hydrogen-bonded supramolecular capsule I compared with coordination capsule II. The external aliphatic groups are omitted for clarity. Note that a pair of intermolecular O—H O hydrogen bonds is replaced by four square-planar Cu-O coordination bonds in the metal-ion insertion process that generates the isostructural inorganic analog. From R. M. McKinley, G V. C. Cave and J. L. Atwood, Proc. Nat. Acad. Sci. 102, 5944-8 (2005). 

Nucleobases and nucleosides are common motifs for hydrogen-bonded supramolecular arrays. Ng et al. first reported a series of phthalocyanine-nucleobase conjugates [64], The tetra-adenine phthalocyanine 64 was prepared by standard <9-alkylation of zinc(II) tetrahydroxyphthalocyanine with 9-(2-bromoethyl)adenine in the presence of K2CO3. The fluorescence of 64 is quenched substantially upon addition of thymine-substituted 9,10-anthraquinone 65, and the rate is much faster compared with that for the situation when the unsubstituted 9,10-anthraquinone is used as the quencher. These results suggest that 64 forms a supramolecular complex with 65 through the Watson-Crick base-pairing interactions. 

Wuest has demonstrated that the pyridone moiety also generates a hydrogen-bonded supramolecular synthon that is suitable for building extended arrays.67 Remarkably, methanetetra(6-phenylethynyl-2-pyridone) exhibits a diamondoid network, sevenfold interpenetration and cavities large enough to enclathrate butyric or valeric acid.27 Wuest introduced the concept of tectons to describe molecules that inherently possess the molecular structure and intermolecular recognition features to predictably self-assemble into crystalline networks. He followed this study with several other examples of diamondoid networks sustained by the pyridone moiety 27c d... 

The uptake of C6o corresponds to the increase in absorbance at 258 and 328 nm in the absorption spectrum of 1 + C6o (Fig. 23). Comparison of a solution of 1 + C6o with a saturated solution of C60 in chloroform showed that the Cgo concentration increased 16-fold in the presence of NDI nanotubes (1). In contrast with these results, the methyl ester of 1, which is unable to form hydrogen-bonded supramolecular nanotubes, did not enhance the solubility of C60 in chloroform, supporting the thesis that the Cfi0 molecules are complexed in the inner nanotubular cavity. The increase in absorbance at 258 nm also led to an estimate of [NDI]/[C6o] stoichiometry, revealing that an average of 3.6 NDI units were encapsulating one Cfi0 molecule. Similar results were also obtained with other amino acid derivatives of NDI. 

Fig.1 Architectures of different hydrogen bonded, supramolecular polymers (A hydrogen-bonding acceptor D = hydrogen-bonding donor)...

An approach towards fibers made from the hydrogen-bonded supramolecular polymer has been reported [213]. Two PS-b-P4VP diblock copolymers... 

Corhin PS, Zimmermann SC (2005) Hydrogen bonded supramolecular polymers linear and network polymers and self-assembhng discotic polymers. CRC press, Boca Raton, El, p 153... 

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