Papers by valeria amendola
John Wiley & Sons, Inc. eBooks, Jan 27, 2010
Anion Receptors Containing -NH Binding Sites: Hydrogen-Bond Formation or Neat Proton Transfer?
Chemistry: A European Journal, 2005
When the amide-containing receptor 1(+) is in a solution of dimethyl sulfoxide (DMSO) in the pres... more When the amide-containing receptor 1(+) is in a solution of dimethyl sulfoxide (DMSO) in the presence of basic anions (CH(3)COO(-), F(-), H(2)PO(4) (-)), it undergoes deprotonation of the -NH fragment to give the corresponding zwitterion, which can be isolated as a crystalline solid. In the presence of less basic anions (Cl(-), Br(-), NO(3) (-)), 1(+) establishes true hydrogen-bond interactions of decreasing intensity. The less acidic receptor 2(+) undergoes neat proton transfer with only the more basic anions CH(3)COO(-) and F(-), and establishes hydrogen-bond interactions with H(2)PO(4) (-). An empirical criterion for discerning neutralisation and hydrogen bonding, based on UV/Vis and (1)H NMR spectra, is proposed.
Some guidelines for the design of anion receptors
Coordination Chemistry Reviews, Jun 1, 2006
Anions can be recognized by either positively charged or neutral artificial receptors. Positive c... more Anions can be recognized by either positively charged or neutral artificial receptors. Positive charges within receptor's cavity can be provided by transition metal ions (eg Cu II ), which offer a binding site to one donor atom of the envisaged anion. Dicopper(II) bistren cryptates are ...
CO <sub>2</sub> Separation by Imide/Imine Organic Cages
Chemistry: A European Journal, Aug 22, 2022
A polyamino cage from a kinetically inert complex of a polytopic open ligand
The extraction of the succinate dianion from a neutral aqueous solution into dichloromethane is o... more The extraction of the succinate dianion from a neutral aqueous solution into dichloromethane is obtained using a lipophilic cage-like dicopper(II) complex as the extractant. The quantitative extraction exploits the high affinity of the succinate anion for the cavity of the azacryptate. The anion is effectively transferred from the aqueous phase, buffered at pH 7 with HEPES, into dichloromethane. A 1:1 extractant:anion adduct is obtained. Extraction can be easily monitored by following changes in the UV-visible spectrum of the dicopper complex in dichloromethane, and by measuring the residual concentration of succinate in the aqueous phase by HPLC−UV. Considering i) the relevance of polycarboxylates in biochemistry, as e.g. normal intermediates of the TCA cycle, ii) the relevance of dicarboxylates in the environmental field, as e.g. waste products of industrial processes, and iii) the recently discovered role of succinate and other dicarboxylates in pathophysiological processes including cancer, our results open new perspectives for research in all contexts where selective recognition, trapping and extraction of polycarboxylates is required. File list (2) download file view on ChemRxiv CHEMRXIV_AMENDOLA.pdf (437.84 KiB) download file view on ChemRxiv SI_CHEMRXIV_AMENDOLA.pdf (2.81 MiB)
Photochemical and photocatalytic properties of transition metal compounds
Photochemistry, 2015
Page 99. Photochemical and photocatalytic properties of transition-metal compounds Andrea Maldott... more Page 99. Photochemical and photocatalytic properties of transition-metal compounds Andrea Maldottia DOI: 10.1039/9781849732826-00088 This contribution covers important developments published in 2010 on the photochemical ...
A Solvent-Dependent and Electrochemically Controlled Self-Assembling/Disassembling System
ChemPlusChem, 2003
Page 1. A SOLVENT-DEPENDENT AND ELECTROCHEMICALLY CONTROLLED SELF-ASSEMBLING/DISASSEMBLING SYSTEM... more Page 1. A SOLVENT-DEPENDENT AND ELECTROCHEMICALLY CONTROLLED SELF-ASSEMBLING/DISASSEMBLING SYSTEM Valeria AMENDOLA a1, Massimo BOIOCCHI b, Yuri DIAZ FERNANDEZ c, Carlo MANGANO a2 and Piersandro PALLAVICINI a3,* ...
Syntheses and evaluation of new hydrophilic azacryptands used as masking agents of technetium in solvent extraction processes
Dalton Transactions, 2021
New azacryptands with the addition of hydrophilic groups were synthesized to bind selectively the... more New azacryptands with the addition of hydrophilic groups were synthesized to bind selectively the pertechnetate anion in nitric acid medium, and avoid its extraction in the separation process.
The synthesis and characterization of a novel film-forming organic cage and of its smaller analog... more The synthesis and characterization of a novel film-forming organic cage and of its smaller analogue are here described. While the small cage produced single crystals suitable for X-ray diffraction studies, the large one was isolated as an amorphous solid. Due to its remarkable film-forming properties, this amorphous cage could be solution-processed into transparent thin-layer films and mechanically stable dense self-standing membranes. Thanks to these peculiar features, the membranes were also successfully tested for gas permeation, reporting a behaviour similar to that found with stiff glassy polymers such as polymers of intrinsic microporosity or polyimides. Considering the growing interest in the development of molecular-based membranes, e.g. for separation technologies and functional coatings, the properties of this organic cage were investigated by thorough analysis of their structural, thermal, mechanical and gas transport properties, and by detailed atomistic simulations.
Chemistry – A European Journal
Benzene is a highly toxic aromatic hydrocarbon. Inhaling benzene can cause dizziness, vertigo, he... more Benzene is a highly toxic aromatic hydrocarbon. Inhaling benzene can cause dizziness, vertigo, headaches, aplasia, mutations and, in the most extreme cases, cancer. Trans,trans‐muconic acid (t,t‐MA) is one of the metabolization products of benzene. Although different analytical methods have been reported for the determination of t,t‐MA, these are often expensive, require trained personnel, are not suitable for on‐site measurements, and use hazardous organic solvents. For these reasons, the development of reliable, selective and sensitive methods for rapid and in situ detection of t,t‐MA are of importance. Addressing this challenge, a nanodevice for the selective and sensitive quantification of t,t‐MA in urine is reported. The nanodevice used is achieved using mesoporous silica nanoparticles loaded with a dye reporter and capped with a dicopper(II) azacryptand. Pore opening and payload release is induced rapidly (10 min) and selectively with t,t‐MA in urine, using a simple fluorimete...
CO2 Separation by Imide/Imine Organic Cages
Chemistry – A European Journal
Two novel imide/imine‐based organic cages have been prepared and studied as materials for the sel... more Two novel imide/imine‐based organic cages have been prepared and studied as materials for the selective separation of CO2 from N2 and CH4 under vacuum swing adsorption conditions. Gas adsorption on the new compounds showed selectivity for CO2 over N2 and CH4. The cages were also tested as fillers in mixed‐matrix membranes for gas separation. Dense and robust membranes were obtained by loading the cages in either Matrimid® or PEEK‐WC polymers. Improved gas‐transport properties and selectivity for CO2 were achieved compared to the neat polymer membranes.
CCDC 1971577: Experimental Crystal Structure Determination
Chiroptical sensing of perrhenate in aqueous media by a chiral organic cage
Chemical Communications, 2022
A chiral organic cage is able to detect the surrogate of 99TcO4− in water, fruit juice and artifi... more A chiral organic cage is able to detect the surrogate of 99TcO4− in water, fruit juice and artificial urine medium.
CCDC 992963: Experimental Crystal Structure Determination
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1867681: Experimental Crystal Structure Determination
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
The Interaction of Fluoride with Fluorogenic Ureas: An ON1–OFF–ON2 Response
Journal of the American Chemical Society, 2013
The anion binding tendencies of the two fluorogenic ureas L(1)H and L(2)H, containing the 2-anthr... more The anion binding tendencies of the two fluorogenic ureas L(1)H and L(2)H, containing the 2-anthracenyl and 1-pyrenyl moieties as signaling units, respectively, have been investigated in MeCN and DMSO by absorption, emission, and (1)H NMR spectroscopies. The formation of stable 1:1 receptor:anion H-bond complexes has been confirmed by structural studies on the crystalline [Bu4N][L(1)···Cl] and [Bu4N][L(2)H···CH3COO] salts. Complexation induces significant variations of the emission properties of L(1)H and L(2)H according to a multifaceted behavior, which depends upon the fluorogenic substituent, the solvent, and the basicity of the anion. Poorly basic anions (Cl(-), Br(-)) cause a red shift of the emission band(s). Carboxylates (CH3COO(-), C6H5COO(-)) induce fluorescence quenching due to the occurrence of an electron-transfer process taking place in the locally excited complex [*L-H···X](-). However, this excited complex may undergo an intracomplex proton transfer from one urea N-H fragment to the anion, to give the tautomeric excited complex [L···H-X](-)*, which emits at higher wavelength. F(-) displays a unique behavior: It forms with L(1)H a stable [L-H···F](-) complex which in the excited state undergoes intracomplex proton transfer, to give the poorly emissive excited tautomer [L···H-F](-)*. With L(2)H, on moderate addition of F(-), the 1:1 H-bond complex forms, and the blue fluorescence of pyrene is quenched. Large excess addition of F(-) promotes deprotonation of the ground-state complex, according to the equilibrium [L(2)H···F](-) + F(-) ⇆ [L(2)](-) + HF2(-). The deprotonated receptor [L(2)](-) is distinctly emissive (yellow fluorescence), which generates the fluorimetric response ON(1)-OFF-ON(2) of receptor L(2)H with respect to F(-).
Photophysics of transition metal complexes
Photochemistry
Page 76. Photophysics of transition metal complexes Fausto Puntorieroab DOI: 10.1039/ 97818497328... more Page 76. Photophysics of transition metal complexes Fausto Puntorieroab DOI: 10.1039/ 9781849732826-00065 This report summarises the literature reported in 2010 on the photophysical properties of metal complexes and their polynuclear supramolecular assem-blies. ...
New Journal of Chemistry, 2016
A new macrobicyclic ligand capable of binding two Cu 2+ cations has been synthesized and its prot... more A new macrobicyclic ligand capable of binding two Cu 2+ cations has been synthesized and its protonation and coordinative properties fully determined in aqueous solution. A thioether moiety was appended on the ligand backbone. This does not influence the ligand coordination ability but allows us to graft its bis-copper complex on the surface of a self-assembled monolayer of gold nanostars (GNS), in turn grafted on glass slides pre-functionalized with a layer of a silane-bearing polyethyleneimine polymer. The release of copper ions from the GNS monolayers was also investigated, finding a general agreement with the coordination properties of the complex in solution, although the bis-copper complex displays an increased kinetic inertness when grafted on the glass slides. The photothermal properties of the GNS monolayer were studied with and without the overlayer of the Cu 2+ complex, finding no influence of the latter but disclosing that the bis-copper complex detachment is promoted by local T increase due to laser irradiation.
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Papers by valeria amendola