Mononuclear rearrangement of heterocycles in ionic liquids catalyzed by copper(II) salts

2008

Abstract The reactivity of E- and Z-phenylhydrazones of 3-benzoyl-5-phenyl-1,2,4-oxadiazole in the presence of CuCl2 and Cu(ClO4)2·6H2O has been studied in four imidazolium ionic liquids [bmim][X] (X=BF4−, PF6−, SbF6− and CF3SO3−). The reaction may follow different mechanistic patterns, depending on the nature of the ionic liquid anion, accounting for both qualitative and kinetic data. In the presence of CuCl2, two processes take place at the same time, i.e., the E⇆Z isomerization and the rearrangement of Z-isomer into the relevant 4-benzoylamino-2,5-diphenyl-1,2,3-triazole. In contrast, in the presence of Cu(ClO4)2·6H2O, the rearrangement occurs only in solution of [bmim][BF4] and [bmim][C…

The effect of the cation p-surface area on the 3D organization and catalytic ability of imidazolium-based ionic liquids

2011

The dichotomic nature of ionic liquids (ILs, simple solvents or supramolecular fluids) induced us to carry out a structural investigation of some mono-and dicationic ionic liquids using 1D and 2D NMR, resonance light scattering, and UV/Vis spectroscopy. Ionic liquids with different cation π-surface areas were used, namely [bmim][NTf2], [Bzmim][NTf 2], [Bzbim][NTf2], [p-Xyl-(bim)2][NTf 2]2, and [m-Xyl-(bim)2][NTf2] 2 [bmim = 1-butyl-3-methylimidazolium, Bzmim = 1-benzyl-3- methylimidazolium, Bzbim = 1-benzyl-3-butylimidazolium, NTf2 = bis(trifluoromethansulfonyl)imide]. In order to verify to what extent the structural investigation, coupled with the determination of solvent parameters, could…

Task Specific Dicationic Ionic Liquids: Recyclable Reaction Media for the Mononuclear Rearrangement of Heterocycles

2014

Nine functionalized dicationic ionic liquids were used to study the base catalyzed mononuclear rearrangement of (Z)-phenylhydrazone of 3-benzoyl-5-phenyl-1,2,4-oxadiazole into the corresponding triazole at 363 K. Ionic liquids were characterized by the presence of 1-(1-imidazolylmethyl)-3,5-di[1-(3'-octylimidazolylmethyl)]benzene cation, bearing on the structure a neutral imidazole unit as basic functionality. Besides anions generally used for monocationic ionic liquids, such as [Br(-)], [BF4(-)], and [NTf2(-)], also dianions having a rigid aromatic spacer such as 1,4-benzenedicarboxylate, 2,6-naphthalenedicarboxylate, and 1,5- and 2,6-naphthalenedisulfonate were taken into account. Further…

On the Rearrangement in Dioxane/Water of (Z)-Arylhydrazones of 5-Amino-3-benzoyl-1,2,4-oxadiazole into (2-Aryl-5-phenyl-2H-1,2,3-triazol-4-yl)ureas: …

2006

We have recently evidenced an interesting differential behavior in the reactivity in dioxane/water between the (Z)-2,4-dinitrophenylhydrazone (1a) and the (Z)-phenylhydrazone (1b) of 5-amino-3-benzoyl-1,2,4- oxadiazole. The former rearranges into the relevant triazole 2a only at pS+ > 4.5 while undergoing hydrolysis at high proton concentration (pS+ < 3.5); on the contrary, the latter rearranges into 2b in the whole pS+ range examined (0.1 e pS+ e 14.9). Thus, for a deeper understanding of these differences we have now collected kinetic data on the rearrangement in dioxane/water of a series of 3- or 4-substituted (Z)-phenylhydrazones (1c-l) of 5-amino-3-benzoyl-1,2,4-oxadiazole in a wide ra…

Molecular “Pincer” from a Diimidazolium Salt: A Study of Binding Ability

2013

The anion recognition ability of the dicationic imidazolium salt 3,3′-di-n-octyl-1,1′- (1,3-phenylenedimethylene)diimidazolium 1,5-naphthalenedisulfonate ([m-Xyl-(oim)2][1,5-NDS]) was investigated in acetonitrile solution by means of proton NMR titrations. A wide range of anions, comprising simple inorganic ions, halides, and mono- and dicarboxylates was taken into account. The study showed that this receptor binds carboxylate anions more strongly than halides. Moreover [m- Xyl-(oim)2][1,5-NDS] displays selectivity for di- over monocarboxylate anions. The complex stability was mainly affected by the anion basicity in the presence of monocarboxylates, whereas the flexibility of the alkyl cha…

Ionic liquid gels and antioxidant carbon nanotubes: Hybrid soft materials with improved radical scavenging activity

2019

Hypothesis: Performances of materials are frequently affected by the action of radicals that can induce their degradation. To overcome the above issue, natural antioxidants (AOs) can be added during manufacturing. Considering the high instability of AOs, they have been adsorbed on carbon nanomaterials surface. However, the inclusion of functionalized carbon nanomaterials into gel matrix could enhance the antioxidant efficiency and represent an easy way to disperse and handle the active species.Experiments: Carboxypropyl functionalized carbon nanotubes (f-CNT), pure or with physically adsorbed alpha-tocopherol (f-CNT-VE) and quercetin (f-CNT-Q), were incorporated in some ionic liquid gels (I…

Carbon-based ionic liquid gels: alternative adsorbents for pharmaceutically active compounds in wastewater

2021

With the aim of obtaining adsorbent systems to be used for the removal of pharmaceutically active compounds (PhACs) from wastewater, some hybrid ionic liquid gels (HILGs) were obtained from the combination of ionic liquid-based supramolecular gels and carbon materials, like graphite, graphene and graphene oxide (graphene OX). The properties of HILGs were investigated by determining their gel–sol transition temperature and rheological features. They were tested for the removal of PhACs belonging to different pharmaceutical classes, like antibiotics, antidepressants, anti-inflammatory. In particular, the removal of carbamazepine (CBZ), diclofenac sodium salt (DCF), ciprofloxacin (CPX) and nal…

Fluorescent naphthalimide-imidazolium hydrogels for biomedical applications

2019

Bioimaging and in vivo imaging are cornerstone technologies in support of biomedical diagnosis. However, in some cases imaging methods have increased cancer risks for patients. Moreover, the most widely used diagnostic medical imaging technique, X-ray imaging, is the largest man-made source of radiation exposure to the general population. Thus, the research of new efficient and less invasive materials for imaging is quite urgent. Supramolecular hydrogels have recently proved to be promising biological carriers to load versatile bioimaging agents for in vitro or in vivo bioimaging, thanks to the ability to undergo reversible swelling and gel–sol transition in response to various physiologica…

TASK SPECIFIC IONIC LIQUIDS: CATALIZZATORI ECOCOMPATIBILI PER LA DEPOLIMERIZZAZIONE DELLE PLASTICHE

Geminal Imidazolium Salts: A new Class of Gelators

2012

The gelling behavior of some geminal diimidazolium salts was investigated in solvents differing in polarity and hydrogen bond donor ability. The used salts, namely the 3,3'-di-n-decyl-1,1'(1,4-phenylenedimethylene)diimidazolium dibromide [p-Xyl-(decim)(2)][Br](2) (1), the 3,3'-di-n-dodecyl-1,1'(1,4-phenylenedimethylene)diimidazolium dibromide [p-Xyl-(dodecim)(2)][Br](2) (2), and the 3,3'-di-n-dodecyl-1,1'(1,4-phenylenedimethylene)diimidazolium ditetrafluoroborate [p-Xyl-(dodecim)(2)][BF(4)](2) (3), differ in the alkyl chain length and in the anion properties, such as size, shape, and coordination ability. In all cases in which gelation process was observed, the obtained gels were characteri…

Amino acid-based cholinium ionic liquids as sustainable catalysts for pet depolymerization

2021

Chemical recycling to monomers is one of the key strategies in tackling the issues deriving from persistent plastic pollution in the environment, and poly(ethylene terephthalate) (PET) is among the most used polymers in modern society. In this context, we herein describe the glycolysis of PET to bis-hydroxyethyl terephthalate (BHET), promoted by basic cholinium salts differing for the anions, also comprising amino acid anions. We investigated the optimal reaction conditions, finding that the best-performing catalyst is [Ch][Gly], in the presence of which a conversion of 85% and a yield of 51% are achieved at 150 °C after 6 h, from PET deriving from a clear water bottle. We used our protocol…

Fluorescent interaction Eu-IL: when the anion plays a role

2020

Insights into the effect of the spacer on the properties of imidazolium based AIE luminogens

2021

Abstract With the aim to obtain organic salts with potential applications in high performance molecular electronics, we combined properties of π-conjugated spacers, like 1,4-diethynylbenzene and 1,6-diethynylpyrene, with the ones of both imidazole and imidazolium units. Physico-chemical properties of obtained fluorescent organic salts were investigated performing thermo-gravimetric analysis (TGA), differential scanning calorimetry (DSC) and cyclic voltammetry measurements (CV). Photophysical behavior of the salts was analyzed in conventional solvents and ionic liquids, by UV–vis and fluorescence investigation. Solution phase aggregation study revealed that these salts self-assemble in conve…

Two-Component Hydrogels Formed by Cyclodextrins and Dicationic Imidazolium Salts

2013

In the framework of our recent interest in studying the gelling behaviour of imidazolium salts, we took into account the possibility of obtaining two-component hydrogels by combining cyclodextrins and dicationic imidazolium salts. In particular, we used diimidazolium salts differing in the alkyl chain length and in the size, shape, and coordination ability of the anion, namely the 3,3′-di-n-decyl- and 3,3′-di-n-dodecyl-1,1′-(1,4-phenylenedimethylene)diimidazolium dibromide, and 3,3′-di-n-dodecyl-1,1′-(1,4-phenylenedimethylene)diimidazolium ditetrafluoroborate and dihexafluorophosphate. As far as cyclodextrins are concerned, to gain information on the effects of different sized cyclic oligos…

Acid- and Base-Catalysis in the Mononuclear Rearrangement of Some (Z)-arylhydrazones of 5-Amino-3-benzoyl-1,2,4-oxadiazole in Toluene: Effect of Subs…

2011

The reaction rates for the rearrangement of eleven (Z)-arylhydrazones of 5-amino-3-benzoyl-1,2,4-oxadiazole 3a-k into the relevant (2-aryl-5-phenyl-2H-1, 2,3-triazol-4-yl)ureas 4a-k in the presence of trichloroacetic acid or of piperidine have been determined in toluene at 313.1 K. The results have been related to the effect of the aryl substituent by using Hammett and/or Ingold-Yukawa-Tsuno correlations and have been compared with those previously collected in a protic polar solvent (dioxane/water) as well as with those on the analogous rearrangement of the corresponding (Z)-arylhydrazones of 3-benzoyl-5-phenyl-1,2,4-oxadiazole 1a-k in benzene. Some light can thus be shed on the general di…

Tunable radical scavenging activity of carbon nanotubes through sonication

2016

Abstract Carbon nanotubes (CNTs) having controlled radical scavenging activity have been achieved tuning the content of their lattice defects induced by an ultra-sound (us) treatment. The reactivity of CNTs, subjected to ultra-sonication for different time intervals, toward 1,1-diphenyl-2-pycryl (DPPH) and hydroxyl (•OH) radicals has been estimated and related to defect concentration, evaluated through Raman spectrometry. The radical scavenging efficiency of ultra-sound treated CNTs (us-CNTs) increases with increasing the content of the structural defects, suggesting that the defect resulting from us treatment can be capitalized to obtain an amplified and controlled radical scavenging activ…

Chemo-enzymatic Conversion of Glucose in 5-Hydroxymethylfurfural: The Joint Effect of Ionic Liquids and Ultrasound

2020

For the valorization of lignocellulosic biomass, a key step is unlocking the conversion of glucose to suitable chemical platforms. To this aim, we herein describe the sequential chemo-enzymatic conversion of glucose into 5-hydroxymethylfurfural (5-HMF), in two steps: glucose isomerization to fructose, catalyzed by glucose isomerase (GI) and fructose dehydration to 5-HMF promoted by Amberlyst 15. The novelty of our approach lies in the use of crude cell extracts of Streptomyces coelicolor showing GI activity, as isomerization catalysts, along with a commercial immobilized GI. Under optimized reaction conditions, we obtained a conversion to 5-HMF (C5‑HMF) from glucose of 50% in the H2O/[bmim]…

Biochar Particles Obtained from Agricultural Carob Waste as a Suitable Filler for Sustainable Biocomposite Formulations

2022

In the context of sustainable and circular economy, the recovery of biowaste for sustainable biocomposites formulation is a challenging issue. The aim of this work is to give a new life to agricultural carob waste after glucose extraction carried out by a local factory for carob candy production. A pyrolysis process was carried out on bio-waste to produce biofuel and, later, the solid residual fraction of pyrolysis process was used as interesting filler for biocomposites production. In this work, biochar particles (BC) as a pyrolysis product, after fuels recovery of organic biowaste, specifically, pyrolyzed carobs after glucose extraction, were added on poly(butylene-adipate-co-terephthalat…

Naphthalimide imidazolium-based supramolecular hydrogels as bioimaging and theranostic soft materials

2020

1,8-Naphthalimide-based imidazolium salts differing for the alkyl chain length and the nature of the anion were synthesized and characterized to obtain fluorescent probes for bioimaging applications. First, their self-assembly behavior and gelling ability were investigated in water and water/dimethyl sulfoxide binary mixtures. Only salts having longer alkyl chains were able to give supramolecular hydrogels, whose properties were investigated by using a combined approach of fluorescence, resonance light scattering, and rheology measurements. Morphological information was obtained by scanning electron microscopy. In addition, conductive properties of organic salts in solution and gel state we…

Liquidi ionici biocompatibili come leganti per sistemi termocromici

Studio dell’interazione Im-Eu-X: nuovi leganti ecocompatibili per l’Europio

Prediction of ionic liquid's heat capacity by means of their in silico principal properties

2016

The in silico principal properties (PPs) of ionic liquids (ILs), derived by means of the VolSurf+ approach, were used to develop a Partial Least Squares (PLS) model able to find a quantitative correlation among IL descriptors (accounting for both cationic and anionic structural features) and heat capacity values, providing affordable predictions validated by experimental Cp measurements for an external set of ILs. In silico predictions allowed the selection of a limited number of structurally different ILs with similar Cp values, providing the possibility to select an optimal IL according to efficiency, as well as to environmental and economic sustainability. The present general procedure, …

Apolar versus polar solvents: a comparison of the strength of some organic acids against different bases in toluene and in water

2010

The constants of ion-pair formation with 3-nitroaniline (3NO(2)A) for eight halogenoacetic acids (HAAs, 3a-h: TFA, TCA, TBA, DFA, DCA, DBA, MCA, and MBA), and five 2,2-dichloroalkanoic acids containing 3-8 carbon atoms (HAs, 5a-e: DCPA, DCBA, DCMBA, DCVA, and DCOA) have been determined in TOL at 298.1 K. The results obtained brought to evidence for HAAs the formation of ion-pairs with two different stoichiometries (base-acid, 1:1 or 1:2), while in contrast the HAs furnish only the 1:1 pairs. The different steric and electronic requirements of HAAs and HAs seem to be responsible for such an unlikely behavior. At the same time, the acid-catalyzed MRH of the (Z)-phenylhydrazone of 5-amino-3-be…

Binary Mixtures of Ionic Liquids: A Joint Approach to Investigate their Properties and Catalytic Ability

2012

The growing interest in the properties and applications of ionic liquids has recently led to research into the possibility of using their binary mixtures. This work reports on the effects of binary mixtures of ionic liquids on the outcome of organic reactions such as the mononuclear rearrangement of heterocycles and the solvatochromic behavior of Nile Red. Binary mixtures formed by ionic liquids differing in the structure of the cation and the anion are taken into account. In particular, ionic liquids such as 1-benzyl-3- butylimidazolium bis(trifluoromethanesulfonyl)imide, 1-(2,3,4,5,6- pentafluorobenzyl)-3-butylimidazolium bis(trifluoromethanesulfonyl)imide, and 1-benzyl-3-butylimidazolium…

Organic Salts as Tectons for Self-assembly Processes in Solution

2022

The literature, covering the last decade, about the self-assembly processes of organic salts in conventional solvents was analyzed. In particular, data reported about imidazolium and ammonium salts have been considered. The analysis shows that these processes are highly determined by structural features of the salts. Indeed, besides the nature of the cationic head, features of the alkyl chain borne on the cation structure and its possible functionalization, as well as the nature of the anion play a pivotal role. These factors determine not only the nature of the solvent in which the process occurs but also the nature of the self-assembly mechanism. Consequently, the structure tunability of …

IONOGEL IBRIDI: SISTEMI ADSORBENTI PER LA RIMOZIONE DI COMPOSTI FARMACEUTICI DALLE ACQUE INQUINATE

Interplay of acidity and ionic liquid structure on the outcome of a heterocyclic rearrangement reaction

2021

The study of suitable probe reactions is a powerful tool to investigate the properties of nonconventional solvents such ionic liquids (ILs). In particular, we studied the acid-catalyzed mononuclear rearrangement of heterocycles (MHR) of the Z-phenylhydrazone of 5-amino-3-benzoyl-1,2,4-oxadiazole into the relevant 1,2,3-triazole, in solution of ILs by means of kinetic measurements. We chose as solvents six ILs differing both in the cation and anion, in the presence of five carboxylic and sulfonic acids as catalysts. For a useful comparison, the reaction was also performed in 1,4-dioxane and methanol. In general, the reaction occurs faster in ILs, compared to conventional solvents, according …

Activity of a Heterogeneous Catalyst in Deep Eutectic Solvents: The Case of Carbohydrate Conversion into 5-Hydroxymethylfurfural

2019

Obtaining industrially relevant products from renewable resources and developing processes under the light of sustainable chemistry is a prominent endeavor of present-day chemical research. In this context, herein we investigated the dehydration of fructose and sucrose in deep eutectic solvents promoted by the ion-exchange resin Amberlyst 15 as heterogeneous catalyst. We optimized the reaction conditions in terms of temperature, catalyst loading, and initial amount of substrate. Then, we looked at the effect of structural variations in the solvent components on the reaction outcome. Under the best experimental conditions, we obtained very good yields of 78% at 60 °C and 69% at 80 °C for fru…

Organic salts and aromatic substrates in two-component gel phase formation: the study of properties and release processes

2015

To identify gel phases able to act as confined reaction media or materials for the removal of organic pollutants, we studied two-component gel phases formed by naphthalenedisulfonate diimidazolium salts in the presence of some organic guests, in 1-propanol solution. Guests differing in π-surface area, bulkiness and electronic properties were taken into account. Soft materials obtained were investigated for their thermal stability, self-repairing ability and morphology. Furthermore, two-component gel phase formation was studied using resonance light scattering (RLS) measurements. Guest release processes from the gel phase were also studied. These processes were monitored as a function of tim…

A joint action of deep eutectic solvents and ultrasound to promote Diels−Alder reaction in a sustainable way

2020

The need to reduce environmental impact of chemical processes has induced a surge of attention in the choice of solvent and methodologies to carry them out. In this context, we studied the Diels−Alder reaction using N-ethylmaleimide as dienophile and changing the nature of the diene in deep eutectic solvents (DES) under both conventional heating and ultrasonic activation. DES obtained by the combination of different hydrogen bond acceptors and donors allowed assessing the role played by solvent nature. DES proved suitable solvent media for the target reaction, allowing higher yields and faster reactions compared to conventional organic solvents. The trend of yields, both in silent and under…

Improvement of oxidation resistance of polymer-based nanocomposites through sonication of carbonaceous nanoparticles

2020

Abstract The work aim is focused on two different aspects: first, the investigation of the effect of extended ultra-sound-assisted treatment (us) of carbonaceous nanoparticles, such as carbon nanotubes (CNTs) and carbon black (CB), on their radical scavenging activity, and second, the investigation of the oxidative resistance of polymer-based nanocomposites, containing us-treated CNTs and CB. Particularly, the CNTs and CB have been subjected to us sonication for different time intervals and the performed analysis reveals that both kinds of nanoparticles show decreased average hydrodynamic diameters and large content of surface defects. Really, the increased content of CNTs and CB defects, a…

The Gelling Ability of Some Diimidazolium Salts: Effect of Isomeric Substitution of the Cation and Anion

2013

The gelling ability of some geminal imidazolium salts was investigated both in organic solvents and in water solution. Organic salts differing either in the cation or anion structure were taken into account. In particular, the effects on the gel-phase formation of isomeric substitution on the cation or anion as well as of the use of mono- or dianions were evaluated. As far as the cation structure is concerned, isomeric cations, such as 3,3′-di-n-octyl-1,1′-(1,4-phenylenedimethylene)diimidazolium and 3,3′-di-n-octyl-1,1′-(1,3-phenylenedimethylene)diimidazolium, were used. On the other hand, in addition to the bromide anion, isomeric dianions, such as the 1,5- and 2,6-naphthalenedisulfonate a…

Catalysis in Supramolecular Systems: the Case of Gel Phases

2021

Supramolecular gels are a fascinating class of materials, originated by the self-assembly of low molecular weight molecules. Underpinned by non-covalent interactions, they find application in a diverse range of fields. Among these, supramolecular gels can be considered as organized, non-conventional reaction media, able to influence reactivity in a radically different way, compared with what happens in solution. This short review will focus on this aspect, covering literature from 2010 onwards, addressing the application of supramolecular gels as reaction media. In particular, in the first section we explore organocatalytic reactions in gel phase, with wide synthetic relevance, such as aldo…

On the use of multi-parameter free energy relationships: the rearrangement of (Z)-arylhydrazones of 5-amino-3-benzoyl-1,2,4-oxadiazole into (2-aryl-5…

2010

Abstract By using a multi-parameter approach (a combination of Hammett/Ingold-Yukawa-Tsuno/Fujita-Nishioka free energy relationships) the mononuclear rearrangements of heterocycles (MRH) rates for five new ortho-substituted and ten new di-, tri-, or tetra-substituted (Z)-arylhydrazones of 5-amino-3-benzoyl-1,2,4-oxadiazole into the relevant (2-aryl-5-phenyl-2H-1,2,3-triazol-4-yl)ureas (in dioxane/water and in a large range of pS+ values) have been related to the electronic and proximity effects exerted by the present substituents, also considering previous results on some mono meta- and para-substituted (Z)-arylhydrazones. In every case, excellent correlation coefficients have been calculat…

Ionic liquid binary mixtures: How different factors contribute to determine their effect on the reactivity

2016

We studied how mixing ionic liquids affected the rate of the Diels Alder reaction between 9-anthracenemethanol and N-ethylmaleimide. The mixtures considered spanned the whole compositional range and differed for the anion or the cation. These comprised mixtures of the ionic liquid 1-benzyl-3-butyl-imidazolium bis-(trifluoromethanesulfonyl)imide ([Bzbim][NTf2]) with 1-(2,3,4,5,6-pentafluorophenyl)-3-butyl-imidazolium bis-(trifluoromethanesulfonyl)imide ([Bz(F5)bim][NTf2]) or 1-benzyl-3-butyl-imidazolium tetrafluoroborate ([Bzbim][BF4]). Moreover we studied the reaction in a set of mixtures containing an aliphatic and an aromatic cation, namely [Bzbim+] and N-butyltriethylammonium ([bEt3N+]) …

Aggregation processes of perylene bisimide diimidazolium salts

2015

The supramolecular aggregation of three diimidazolium- functionalized perylene bisimides, differing in the alkyl chain length was investigated. These salts form aggregates in solvents like chloroform, dichloromethane, and glycerol. Solvent-, concentration-, and temperature-dependent spectroscopic studies were carried out, evidencing the occurrence of an isodesmic, enthalpy-driven aggregation process, underpinned by p–p stacking and hydrogen bonding. Moreover, dynamic light scattering (DLS) measurements and SEM images revealed that these salts aggregate in chloroform into elongated structures.

Self-Sustaining Supramolecular Ionic Liquid Gels for Dye Adsorption

2018

Water contamination is one of the main problems of modern society, and scientific research is continuously involved in identifying solutions able to preserve this valuable source. In this context, we characterized novel ionogels formed by organic salts with different anions. In particular, they show self-strengthening behavior, a quite unusual property for supramolecular gels, and they also exhibit a good load-bearing capacity. These ionogels are able to remove cationic dyes from wastewater. Thanks to their properties, they can be used in different apparatuses like dialysis membranes and as loading in adsorption columns. In the latter case over 95% removal is achieved in less than 10 min. I…

Ionic liquids: “normal” solvents or nanostructured fluids?

2021

Ionic liquids (ILs) are a class of non-conventional solvents, which, for almost two decades, have continued to generate burgeoning interest in different fields of present-day chemical research with few similar precedents. Among the various aspects related to ILs, a topic worthy of in-depth analysis is their influence on organic reactivity and reaction rates. In light of this, the present short review aims to provide an overview of the literature from 2010 to the present day that addresses this issue. In particular, we herein present two main different viewpoints by which the solvent effect of ILs is explained: the first is mainly based on considering the bulk polarity of ILs and linear solv…

Photochemical isomerization of aryl hydrazones of 1,2,4-oxadiazole derivatives into the corresponding triazoles

2012

The photochemical version of the Boulton-Katritzky reaction has been studied, examining the behaviour of the arylhydrazones of 3-benzoyl-5-X-1,2,4-oxadiazoles. The effect of several modifications of the substrates structure (the E and/or Z structures of arylhydrazones, the possible presence of substituents in the arylhydrazono moiety, and the nature of substituents at C-5 of the 1,2,4-oxadiazole ring) on the course of the photochemical rearrangement has been examined.

Solvatochromic behaviour of new donor–acceptor oligothiophenes

2021

Oligothiophene derivatives play a central role in the formulation of materials used in devices in the field of organic electronics. In this work, we report the results of the study of UV-vis absorption and fluorescence spectra, in several solvents, of a series of oligothiophenes recently synthesized in our laboratory. The studied oligothiophenes present different structures due to several factors: the donor– acceptor (D–A) or acceptor–donor–acceptor (A–D–A) architecture, the number of thiophene rings in the backbone (ranging from three to eight), the number and position of solubilizing octyl chains in the backbone, and the type of acceptor moieties (from Knoevenagel condensation either with…

Antimicrobial and antioxidant supramolecular ionic liquid gels from biopolymer mixtures

2023

In this work, we describe the preparation and characterization of supramolecular ionic liquid gels based on binary mixtures of biopolymers, comprising chitosan, chitin, cellulose and lignin. The gels were obtained in ionic liquids differing in the cation or the anion, with no need for a cross-linking agent or acid treatment. The materials obtained were characterized for the minimum gelation concentration, porosity, swelling and rheological properties, finding a prominent influence of the nature of the ionic liquid anion. Then, we investigated the ability of the gels to scavenge free radicals, finding that the gels exhibit a higher antioxidant ability than their individual components. Moreov…

Ionic liquid binary mixtures: Promising reaction media for carbohydrate conversion into 5-hydroxymethylfurfural

2014

Abstract The conversion of carbohydrates into 5-hydroxymethylfurfural (5-HMF) has been studied in binary mixtures of ionic liquids (ILs), using strongly acidic resin Amberlyst 15 as the catalyst. In particular, both mono- and disaccharides, such as fructose, glucose and sucrose have been investigated. Considering the favorable effect exerted by chloride-based ionic liquids in the dissolution of carbohydrates, we used binary mixtures of 1-butyl-3-methylimidazolium chloride ([bmim][Cl]) with [bmim + ] based ionic liquids differing in size, shape and coordination ability of the anion ([bmim][BF 4 ], [bmim][N(CF 3 SO 2 ) 2 ], [bmim][N(CN) 2 ], [bmim][SbF 6 ] and [bmim][CF 3 SO 3 ]). Carbohydrat…

The anion impact on the self-assembly of naphthalene diimide diimidazolium salts

2017

Naphthalene diimide diimidazolium salts differing in the anion nature were synthesized and their properties as well as their self-assembly behaviour were investigated. In particular, we took into consideration the N,N′-bis-(1-octyl-3-propylimidazolium)-naphthalene diimide cations and anions differing in size, shape and coordination abilities like [I−], [BF4−] and [NTf2−]. After determination of thermal behaviour, using differential scanning calorimetry and thermal gravimetric analysis, the electrochemical stability and redox properties were assessed using cyclic voltammetry. The self-assembly behaviour of the salts was investigated using concentration and temperature-dependent spectroscopic…

Isomerization and rearrangement of (E)- and (Z)-phenylhydrazones of 3-benzoyl-5-phenyl-1,2,4-oxadiazole: evidence for a “new” type of acid-catalysis …

2008

A kinetic investigation in methanol of the title reaction has evidenced the occurrence of two processes: the 1-E1-Z isomerization and the rearrangement of the (Z)-isomer into the relevant 4-benzoylamino-2,5-diphenyl-1,2,3-triazole (1-Z  T). The latter reaction is in line with the ability of the (Z)-phenylhydrazones of 3-benzoyl-1,2,4-oxadiazoles to undergo the so called mononuclear rearrangement of heterocycles (MRH). The occurrence of both the examined reactions is dependent on a Lewis-acid-catalysis. The obtained results have shown the possibility of a ‘new’ type of acid-catalysis (bifunctional catalysis by Lewis salts) in the MRH. This catalysis operates through a completely different me…

Environmentally Friendly Eutectogels Comprising l-amino Acids and Deep Eutectic Solvents: Efficient Materials for Wastewater Treatment.

2020

Current concerns for sustainability and the environment make low-impact materials desirable for environmental remediation and, in particular wastewater treatment. We obtained supramolecular gels of l-amino acids in the deep eutectic solvent formed by choline chloride and phenylacetic acid. After gel characterization, and investigating gel-sol transition temperatures, gelation kinetics, rheological properties, and morphology, the gels were applied as sorbents to remove cationic dyes from aqueous solutions. The effects of the pH, dye nature, volume, and concentration of wastewater were analyzed, and the best result was obtained with a l-phenylalanine-based eutectogel. It can be reused for at …

The Role Played by Ionic Liquids in Carbohydrates Conversion into 5-Hydroxymethylfurfural: A Recent Overview

2022

Obtaining industrially relevant products from abundant, cheap, renewable, and low-impacting sources such as lignocellulosic biomass, is a key step in reducing consumption of raw fossil materials and, consequently, the environmental footprint of such processes. In this regard, a molecule that is similar to 5-hydroxymethylfurfural (5-HMF) plays a pivotal role, since it can be produced from lignocellulosic biomass and gives synthetic access to a broad range of industrially important products and polymers. Recently, ionic liquids (ILs) have emerged as suitable solvents for the conversion of biomass and carbohydrates into 5-HMF. Herein, we provide a bird’s-eye view on recent achievements about t…

Supramolecular complexes formed by dimethoxypillar[5]arenes and imidazolium salts: A joint experimental and computational investigation

2017

To gain more insights into the factors acting on the stability of complexes formed by pillar[5]arenes, we investigated the interaction of dimethoxypillar[5]arene with some 1-(n-alkyl)-3-(9-anthracenylmethyl)-imidazolium based organic salts. In particular, we used salts differing in not only the anion nature ([Cl−], [BF4−], [NTf2−] and [SbF6−]) and alkyl chain length (butyl, octyl and dodecylimidazolium derivatives), but also the presence of a hydrogenated or fluorinated tail (octyl and perfluorooctylimidazolium derivatives). Host–guest systems were analysed in solution, solid state and gas phase, using a combined approach of different techniques like fluorescence, 1H NMR, ESI-MS, DSC and DF…

Supramolecular Eutecto Gels: Fully Natural Soft Materials

2018

The obtainment of materials featured by high environmental compatibility is one of the main goals of modern research. On this subject, we herein report the first example of supramolecular gel in deep eutectic solvents. In particular, we prepared gels of the L-amino acids isoleucine and tryptophan in choline chloride/phenylacetic acid 1:2. All gel components are readily available and nontoxic. Gels have been fully characterized by standard gelation tests, rheology, X-ray diffraction, morphology and gelation kinetics. Data collected show that gels properties depend on the gelator nature. In particular, gel phases exhibit strong colloidal forces and, this high mechanical resistance, together w…

The ultrasounds-ionic liquids synergy on the copper catalyzed azide-alkyne cycloaddition between phenyl acetylene and 4-azidoquinoline

2015

Abstract The effect of ultrasound irradiation on the copper catalyzed azide–alkyne cycloaddition between phenylacetylene and 4-azidoquinoline has been studied in solution of different ionic liquids. In particular, we used ionic liquids featuring both aliphatic and aromatic mono- and dications, as well as anions differing in size, symmetry and coordination ability. We also examined the influence of the ionic liquids structural features on the reaction outcomes, finding that under magnetic stirring reactivity is favorably affected by the solvent structural organization, while under sonochemical conditions an opposite trend was observed. In all cases examined, sonochemical activation leads to …

Aryl azides formation under mild conditions: a kinetic study in some ionic liquid solutions.

2009

The kinetics of nucleophilic aromatic substitution of three nitrothiophene derivatives in different [1-butyl-3-methylimidazolium][N(3)]/ionic liquid binary mixtures was studied spectrophotometrically at 298 K. Ionic liquids differing for cation structure (imidazolium or pyrrolidinium) and for size, shape, and coordination ability of the anion ([BF(4)(-)], [PF(6)(-)], [SbF(6)(-)], and [NTf(2)(-)]) were used. Furthermore, in order to have a comparison with conventional organic solvents, the target reaction was also carried out in DMF solution at increasing concentration of NaN(3) or [bmim][N(3)]. Data collected show that the reaction occurs faster in DMF than in ionic liquid solution. Further…

Insights into the anion effect on the self assembly of perylene bisimide diimidazolium salts

2017

Abstract We studied how changing the anion affects the self-assembly of three diimidazolium salts bearing a perylene bisimide spacer. In particular we used [BF 4 − ] and [NTf 2 − ] based salts together with a mixed salt bearing both [I − ] and [BF 4 − ] anions. Thermal as well as concentration and temperature dependent spectroscopic investigations revealed that changing the anion impacts on solid state and solution aggregation, leading to articulate thermotropic behaviors and contrasting solvent effects, respectively. We also studied the electrochemical behavior of the salts to verify if changing the anion alters the redox properties of the salts. Finally, different anions also lead to very…

Bio-based chitosan and cellulose ionic liquid gels: polymeric soft materials for the desulfurization of fuel

2022

Desulfurization of fuel that avoids the introduction in the atmosphere of toxic sulfur volatile compounds, usually formed during combustion, is a viable strategy to reduce pollution. To find new efficient and eco-sustainable adsorbent materials, bio-based polymers such as chitosan (CS), cellulose (CE) and cellulose acetate (CEOAc) were dissolved in ionic liquids (ILs) to form ionic liquid gels (ILGs). Gelling and swelling ability, porosity, morphology, rheology and mechanical response were studied as a function of the polymer and ionic liquid (IL) used. The best performing gels were tested for fuel desulfurization using a fuel mimicking solution of thiophene (T), benzothiophene (BT) and dib…

Ionic Liquid Binary Mixtures, Zeolites, and Ultrasound Irradiation: A Combination to Promote Carbohydrate Conversion into 5-Hydroxymethylfurfural

2019

The efficient conversion of biomass into value-added compounds under mild and safer conditions is a cornerstone of present research efforts to meet the needs of the chemical industry with sustainable development. In this work, we studied the dehydration of fructose, glucose, and sucrose into 5-hydroxymethylfurfural (5-HMF), catalyzed by HY zeolite, in three ionic liquid mixtures differing for the cation, aromatic, or aliphatic. We investigated the effect of several operational parameters such as temperature, catalyst loading, zeolite counterion, solvent mixture, and added chloride. In the optimal experimental conditions, we obtained good conversions to 5-HMF especially for fructose and sucr…

How Ionic Liquid Gels Work on the Removal of Bisphenol A from Wastewater

2022

The occurrence of emerging pollutants in water bodies is a pressing issue of modern society and identifying materials to remove them is the main target of current research. In this work, we prepared and characterized supramolecular gels of 1,3:2,4-dibenzylidene-d-sorbitol (DBS) in ionic liquids differing for the anion and the aliphatic or aromatic nature of the cation. We characterized our gels for their thermal stability and mechanical properties. We also found that all gels self-heal in 24 h after being cut by a razor blade. We then used our gels as sorbents to remove bisphenol A, an endocrine disruptor compound, from aqueous solutions. All gels adsorb BPA with high removal efficiencies, …

Inside Back Cover: Aggregation Processes of Perylene Bisimide Diimidazolium Salts (Chem. Eur. J. 42/2015)

2015

Self-assembly of fluorescent diimidazolium salts: tailor properties of the aggregates changing alkyl chain features

2016

Searching for new fluorescent organic salts to be used in biomedical and electrochemical field, we conjugated properties of imidazolium salts with the ones of naphthalene diimide core and we obtained some N,N′-bis-(1-alkyl-3-propylimidazolium)naphthalene diimide diiodides. We took into account alkyl chains going from hexyl to dodecyl, as well as hydrogenated and fluorinated alkyl tails. After determination of their thermal behaviour by differential scanning calorimetry, concentration-, and temperature-dependent spectroscopic studies (UV-vis and fluorescence) were performed evidencing the occurrence of isodesmic and enthalpy-driven self-assembly processes. Properties of aggregates were also …

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…

A deep insight into the mechanism of the acid-catalyzed rearrangement of the Z-phenylhydrazone of 5-amino-3-benzoyl-1,2,4-oxadiazole in a non-polar s…

2010

The conversion of the Z-phenylhydrazone of 5-amino-3-benzoyl-1,2,4-oxadiazole (1a) into the relevant 1,2,3-triazole (2a) has been quantitatively studied in toluene in the presence of several halogenoacetic acids (HAAs, 3a–h). Again, the occurrence of two reaction pathways has been pointed out: they require one or two moles of acid, respectively, thus repeating the situation previously observed in the presence of trichloroacetic acid. The observed rate constant ratios (kIII/kII) are only slightly affected by the nature of the acid used. To gain a deeper insight into the action of the acids used we have measured the association constants of the HAAs (3a–h) with 4-nitroaniline (4) in toluene. …

Synthesis of aryl azides: A probe reaction to study the synergetic action of ultrasounds and ionic liquids

2011

Abstract The combined effect of ultrasounds and ionic liquids was used to perform the synthesis of aryl azides by nucleophilic aromatic substitution in ionic liquid/[1-butyl-3-methylimidazolium][N 3 ] binary mixtures. The ultrasounds efficiency was analyzed as a function of the substrate and of the ionic liquid structure. In the first case, both 6π and 10π electrons aryl halides were considered. As far as the ionic liquid structure is concerned, both aromatic and aliphatic ionic liquids were taken into account. Among aromatic cations, the effects due to different ability in giving hydrogen bond or π–π interactions were considered. The use of a geminal ionic liquid having an aromatic spacer …

Task-Specific Organic Salts and Ionic Liquids Binary Mixtures: A Combination to Obtain 5-Hydroxymethylfurfural From Carbohydrates

2019

The increase in energy demand and depletion of fossil fuels are among major issues of modern society. Valorization and transformation of raw materials in products of industrial value represents a challenge. This justifies the growing interest of scientific research towards the identification of suitable media and methodologies able to pursue above goals, paying attention to matter of sustainability. On this subject, we studied sulfonic-acid functionalized diimidazolium salts as catalysts for the conversion of fructose and sucrose to 5-hydroxymethylfurfural (5-HMF) in an ionic liquid mixture. In general, using these salts allowed us to obtain 5-HMF in good yields from both substrates in mild…

Ionic liquids/[bmim][N3] mixtures: promising media for the synthesis of aryl azides by SNAr

2008

The nucleophilic aromatic substitution of some activated aryl or heteroaryl halides has been performed in ionic liquid solution, using the 1-butyl-3-methylimidazolium azide as a nucleophile. The reaction course was studied varying the structures of both substrates and ionic liquids. In particular, in the latter case, the reaction of 2-bromo-5-nitrothiophene was carried out in five different ionic liquids ([bmim][BF 4], [bmim][PF 6], [bmim][NTf 2], [bm 2im][NTf 2], and [bmpyrr][NTf 2]). Finally, for all the substrates considered, a comparison with data obtained in MeOH solution in the presence of NaN 3 was also performed. Data collected indicate that in some cases it is possible to obtain ar…

Ionic liquids gels: Soft materials for environmental remediation

2017

Abstract Hypothesis Nanostructured sorbents and, in particular, supramolecular gels are emerging as efficient materials for the removal of toxic contaminants from water, like industrial dyes. It is also known that ionic liquids can dissolve significant amounts of dyes. Consequently, supramolecular ionic liquids gels could be highly efficient sorbents for dyes removal. This would also contribute to overcome the drawbacks associated with dye removal by liquid–liquid extraction with neat ionic liquids which would require large volumes of extractant and a more difficult separation of the phases. Experiments Herein we employed novel supramolecular ionic liquid gels based on diimidazolium salts b…

Electronic and Steric Effects: How Do They Work in Ionic Liquids? The Case of Benzoic Acid Dissociation

2010

The need to have a measure of the strength of some substituted benzoic acids in ionic liquid solution led us to use the protonation equilibrium of sodium p-nitrophenolate as a probe reaction, which was studied by means of spectrophotometric titration at 298 K. In order to evaluate the importance of electronic effect of the substituents present on the aromatic ring, both electron-withdrawing and -donor substituents were taken into account. Furthermore, to have a measure of the importance of the steric effect of the substituents both para- and ortho-substituted benzoic acids were analyzed. The probe reaction was studied in two ionic liquids differing for the ability of the cation to give hydr…

Polysaccharide-based supramolecular bicomponent eutectogels as sustainable antioxidant materials

2023

In this work, we obtained supramolecular gels in deep eutectic solvents (DES) from polysaccharides like chitosan and chitosan : cellulose composites. We thoroughly characterized our gels by determining the minimum gelation concentration, as well as their porosity and swelling. We also investigated their mechanical properties by rheology, and morphology by scanning electron measurements. These properties were mainly influenced by the number of hydrogen bond sites on the hydrogen bond donor, (HBD), while FTIR-ATR investigation suggested that, upon gelation, cholinium cations interpose between polysaccharide chains affecting interchain hydrogen bonding. Our gels also exhibited self-healing and…

Carbon Nanomaterial Doped Ionic Liquid Gels for the Removal of Pharmaceutically Active Compounds from Water.

2019

Due to large drug consumption, pharmaceutically active compounds (PhACs) can be found as water contaminants. The removal of PhACs is a significant issue, as they can easily overtake traditional purification methods. Because of their surface properties, carbon nanomaterials are among the most efficient materials able to adsorb PhACs. However, their limitation is their recovery after use and their possible leakage into the aquatic system. Consequently, new hybrid supramolecular ionic liquid gels (HILGs) have been designed for the adsorption of some antibiotic drugs (ciprofloxacin and nalidixic acid) from water. The chemical&ndash

Boosting the methanolysis of polycarbonate by the synergy between ultrasound irradiation and task specific ionic liquids

2021

In an attempt to perform polycarbonate chemical recycling in a more sustainable way, we took into consideration the combined use of ultrasound irradiation and task specific ionic liquids. Towards this aim, the methanolysis of polycarbonate, into dimethylcarbonate and bisphenol A, was carried out in the presence of cholinium-based ionic liquids featuring anions derived from amino acids and other eco-friendly species. The target process was optimized in terms of both energy and material amounts as well as in terms of the nature of the catalysts used. The proposed protocol allowed high conversion and yields of bisphenol A to be obtained, under milder conditions compared to the ones so far repo…

CONVERSIONE CHEMO-ENZIMATICA DI GLUCOSIO IN 5-HMF IN MISCELE IL/H2O, PROMOSSA DA ESTRATTO CELLULARE BATTERICO E ULTRASUONI

Functionalised Imidazolium Dicationic Ionic Liquids used as reaction media for base catalyzed organic reactions

Host-guest interactions between DMpillar[5]arene and fluorescent imidazolium salts

Reattività dello Z-fenilidrazone del 5-ammino-3-benzoil-1,2,4-ossadiazolo in toluene in presenza di acidi aloacetici.

2005

Ionic Liquids Binary Mixtures: Promising Reaction Media for Carbohydrates Conversion in 5-HMF

Anion and ionic liquid effects on ionogel phases formation

Geminal organic salts have been recently introduced as the third generation of ionic liquids.1 Like their monocationic precursors they generally show high thermal stability and low corrosiveness, as well as high polarity and structural order degree.2 All these features make them good candidates to be used in the formation of conductive gel phases, that afterwards may find application as organized reaction media or in the preparation of dye sensitized solar cells.3 In this context, we have recently synthesized some task specific geminal organic salts and investigated their behaviour as gelators. The obtained salts were able to gel ionic liquid solutions. In order to have information about th…

Two component chiral gels: a study of properties and behavior as recognition systems

Two components organogels as molecular recognition systems: properties, behavior and future applications

SALI ORGANICI: “TECTONI” PER LO STUDIO DI PROCESSI DI SELF-ASSEMBLY IN SOLVENTI ORGANICI

Reazioni di isomerizzazione e trasposizione di fenilidrazoni in liquidi ionici: catalisi da sali di rame (II)

Ionic Liquids binary mixtures: the influence of the composition on their properties and catalytic ability

New “AIE” Luminogens based on π-conjugated imidazolium salts

Organizzazione strutturale di liquidi ionici mono- e dicationici: un approccio combinato

Diimidazolium-based organic salts as low molecular weight hydro- and organogelator

Task-specific dicationic ionic liquids used as reaction media for Michael addition

Catalisi da Cu(II) nelle reazioni di interconversione di anello: uno studio meccanicistico.

Reactivity of phenylhydrazones in ionic liquids solution: the effect of copper(II) salts

Sali di dialchilimidazolio: dai liquidi ionici agli organogel

New examples of specific base catalysis in mononuclear rearrangements of heterocycles found via a designed modification of the side chain structure

2009

To select suitable candidates for the occurrence of specific-base-catalysis in MRH of (Z)-hydrazones of 3-benzoyl-5-phenyl-1,2,4-oxadiazole we have designed a modification of the side-chain structure by linking a strong electron-withdrawing system to the hydrazono group. Thus we have synthesized the (Z)-semicarbazone (3d), the (Z)-phenylsemicarbazone (3e), and the (Z)-acetylhydrazone (3f) of the above oxadiazole and examined their kinetic behavior in dioxane/water in a large range of proton concentrations (pS + 4.0 14.5). In all the pS+ range examined only a base-catalyzed process has been evidenced (no uncatalysed path occurs). The behavior at the largest pS+ values (the reactivity tends t…

Ionogels formed by geminal imidazolium salts: a preliminary investigation

A study of synergetic effect of ionic liquids and ultrasounds on the aryl azides formation

Influenza dei liquidi ionici sulla reazione di trasposizione eterociclica mononucleare catalizzata da Cu(II)

Catalisi da sali di Cu(II) nelle reazioni di trasposizione eterociclica mononucleare.

Organogel formed by imidazolium salts: molecular recognition processes

Studio delle proprietà di ionogel formati da sali organici dicationici

Ionic liquids binary mixtures and zeolites: a combination to promote carbohydrates conversion into 5-hydroxymethylfurfural

A preliminary study on anion binding ability of geminal diimidazolium salts

Effect of ionic liquids in acid-promoted heterocyclic rearrangement reaction

Ionic Liquids: as the different structural order degree can affect the outcome of a reaction

Acidic imidazolium salts: catalysts for biomass transformation

Self-assembly process of diimidazolium salts: the effect of the alkyl chain length and isomeric substitution

Self-assembly of a fluorescent diimidazolium naphthalene diimide salt: the effect of increasing alkyl chain length

Alkyl chain length effect on the self assembly of diimidazolium naphthalene diimide salts

Two components hydrogels formed by host-guest interactions

Diimidazolium-based supramolecular ionogels for dye removal from wastewaters

The influence of steric effects on the strength of some organic acids in toluene and water

Fully ionic metallogels from dicationic diimidazolium salts

How mixing ionic liquids affects a Diels-Alder reaction

[bmim][F] a TSIL differently acting on aromatic nuclei

Two-Component Hydrogels Formed by Cyclodextrins and Dicationic Imidazolium Salts

2014

In the framework of our recent interest in studying the gelling behaviour of imidazolium salts, we took into account the possibility of obtaining two-component hydrogels by combining cyclodextrins and dicationic imidazolium salts. In particular, we used diimidazolium salts differing in the alkyl chain length and in the size, shape, and coordination ability of the anion, namely the 3,3′-di-n-decyl- and 3,3′-di-n-dodecyl-1,1′-(1,4- phenylenedimethylene)diimidazolium dibromide, and 3,3′-di-n-dodecyl-1, 1′-(1,4-phenylenedimethylene)diimidazolium ditetrafluoroborate and dihexafluorophosphate. As far as cyclodextrins are concerned, to gain information on the effects of different sized cyclic olig…

Miscela binaria liquido ionico/[bmim][N3]: un mezzo efficace per la sintesi di arilazidi mediante SNAr

Reattività dei fenilidrazoni E e Z del 3-benzoil-5-fenil-1,2,4-ossadiazolo in presenza di sali di Cu(II)

Supramolecular aggregation of bis-imidazolium functionalised perylene bisimides

Functionalized Diatonic Ionic Liquids Applied to the Study of Michael Addition