Search results for " Supramolecular"

From self-inclusion and host-guest complexes to channel structures

2012

Various supramolecular interactions are applied as driving forces in self-assembly and molecular recognition processes. Single crystal X-ray diffraction method is especially important for solid-state studies of non-covalent interactions as it reveals their influence on the molecular and supramolecular structures. This paper discusses structures of two completely different types of compounds in which a variety of intermolecular interactions are involved. It will be shown that strong and weak intermolecular hydrogen bonds in N-alkylammonium resorcinarene salts, depending on the type of anion, inclusion of resorcinarene upper rim pendant group or solvent molecules into the cavity, strongly aff…

Ionic Liquid Gels: Supramolecular Reaction Media for the Alcoholysis of Anhydrides.

2019

The search of new enantioselective catalysts, able to promote synthetically useful organic reactions with high levels of asymmetric induction, should be associated with the attention to the suitable reaction medium able to achieve the best efficiency in chemical processes. We have investigated the enantioselective desymmetrization of cyclic meso-anhydrides in nonconventional reaction media such as ionic liquids and supramolecular gels. With this aim, we examined several variables in the reacting system: the nature of ionic liquid used as the reaction medium, the gelation solvent, the structure of the anhydrides, the structure of alcohols, the chiral catalysts, and the reaction conditions, i…

Superfluorinated ionic liquid crystals based on supramolecular, halogen-bonded anions

2016

Unconventional ionic liquid crystals in which the liquid crystallinity is enabled by halogen-bonded supramolecular anions [CnF2 n+1-I⋯I⋯I-CnF2 n+1]- are reported. The material system is unique in many ways, demonstrating for the first time 1) ionic, halogen-bonded liquid crystals, and 2) imidazolium-based ionic liquid crystals in which the occurrence of liquid crystallinity is not driven by the alkyl chains of the cation. Out of the ordinary: The high directionality of halogen bonds and the fluorophobic effect were exploited in the design and synthesis of a new family of unconventional superfluorinated ionic liquid crystals. The liquid crystallinity of the system is driven by halogen-bonded…

Computations on electroactive molecular materials: from donor–acceptor architectures to supramolecular polymers

2017

En la presente tesis, se ha realizado un estudio teórico exhaustivo sobre una gran variedad de sistemas moleculares electroactivos con propiedades ópticas, electónicas y de autoensamblaje interesantes para ser explotadas en electrónica molecular y ciencia de nuevos materiales. Los resultados del trabajo de investigación se resumen en tres secciones de acuerdo con: Arquitecturas dador–acceptor covalentes Se han caracterizado teóricamente las propiedades electrónicas y ópticas de cromóforos dador–aceptor que absorben luz en todo el espectro visible. En particular, los cálculos DFT han proporcionado información sobre los regioisómeros más interesantes de exTTF-DCF para obtener un máximo benefi…

Folate-targeted supramolecular vesicular aggregates as a new frontier for effective anticancer treatment in in vivo model.

2012

Abstract Supramolecular vesicular aggregates (SVAs), made up by self-assembling liposomes and polyasparthydrazide co-polymers conjugated to folic acid molecules were extensively investigated in this manuscript as potential active targeting formulation for anticancer drug delivery. Folate-targeted systems (FT-SVAs) were used to treat breast cancer and to further proof the potential in vivo administration of these systems for the therapeutic treatment for several aggressive solid tumors. The physicochemical and technological parameters of FT-SVAs are suitable for their potential in vivo administration. The chemotherapeutic activity of GEM-loaded FT-SVAs was increased during in vivo experiment…

Complexation and Extraction of PAHs to the Aqueous Phase with a Dinuclear Pt II Diazapyrenium‐Based Metallacycle

2010

New palladium and platinum metallacycles have been synthesized by reaction between a 2,7-diazapyrenium-based ligand and Pd(II) and Pt(II) complexes. The inclusion complexes between the metallacycles and polycyclic aromatic hydrocarbons (PAHs) in CD(3)NO(2) and D(2)O were studied by NMR spectroscopy. The structures of the inclusion complexes of the Pt metallacycle as host with pyrene, phenanthrene, and triphenylene were confirmed by single crystal X-ray crystallography. The association constants between the Pt metallacycle and the selected PAHs were determined in CH(3)CN following the characteristic charge-transfer band displayed in their UV/Vis absorption spectrum. Although in aqueous solut…

Preface

2014

Synthesis of novel polypyridylcarbonylpyridines from triazolopyridines. Building blocks in supramolecular chemistry

2009

The synthesis from triazolopyridines 1, of novel triazolopyridylcarbonylpyridylcarbonyltriazolopyridines (TPyCOPyCOTPy) (tpcpctp) 7, and polypyridylcarbonylpyridines (pPyCOPy) (ppcp) 14, building blocks in supramolecular chemistry, is described. These compounds are interesting polynitrogenated ligands as potential molecular sensors, new magnetic materials, single molecular magnets, or in the emerging science of nanomaterials. Abarca Gonzalez, Belen, Belen.Abarca@uv.es ; Ballesteros Campos, Rafael, Rafael.Ballesteros@uv.es ; Chadlaoui, Mimoun, michad@alumni.uv.es

Induced Chirality in Confined Space on Halogen Gold Complexes

2015

The solubilization of HAuCl4 in toluene within optically active reverse micelles and lamellar structures formed by (1R,2S)-Dodecyl(2-hydroxy-1-methyl-2-phenylethyl)- dimethylammonium bromide (DMEB) has allowed us to evidence the complex phenomenology accompanying the confinement of Au salt within these nanostructures. Together with a chloride/bromide exchange process occurring in the first coordination sphere of an Au ion, UV−vis and electronic circular dichroism (ECD) spectra reveal the appearance of an induced dichroic signal attributable to Au complexes entrapped in the hydrophilic domain of the DMEB chiral nanostructures. Interestingly, change of the effective oxidation state and coordi…

Solid state NMR studies of gels derived from low molecular mass gelators

2016

The emergence of NMR crystallography provides a unique opportunity to study solids, gels and xerogels, thereby providing ample information to elucidate molecular packing in the native gel. This review details the importance as well as the application of solid state NMR spectroscopy combined with other analytical tools to study gels derived from low molecular mass organo- and hydrogelators.