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Natural eutecto gels were prepared combining properties of amino acids with the ones of deep eutectic solvents. Soft materials obtained were fully characterised determining the gel-sol transition temperatures and analysing mechanical and morphological features through rheological measurements and polarised optical microscopy. All eutecto gels were tested as catalytic reaction media for the enantioselective aldol reaction and, the best performing one was also used to carry out the Michael addition. In both cases, eutecto gels proved to have a great potential as sustainable reaction media, allowing to perform processes under mild conditions, obtaining excellent yields and, in some cases, also good enantiomeric excess. Catalytic soft materials can be reused up to five cycles keeping the stereochemical control of the reaction and using a recommended solvent by recent sustainable solvent guidelines. This work was supported by the University of Alicante (VIGROB-316FI) and the Spanish Ministerio de Economia, Industria y Competitividad (PGC2018-096616-B-100). BS thanks Generalitat Valenciana (ACIF/2017/211) for her fellowship. We thank University of Palermo (FFR 2020) for financial support. C. R. thanks Elsevier and Società Chimica Italiana (Reaxys-SCI Small Research Grants 2019/2020; Project title: Supracages) for financial support.

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 fructose and sucrose, respectively. Our catalytic system could also be reused for at least five cycles without loss in yield. Finally, this study evidenced what structural features in the solvent components lead to the highest yields.

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]­[Cl]0.5[BF4]0.5 1:3 w-w ternary mixture. We also carried out both reactions under sonochemical activation, obtaining a conversion to fructose (Cfructose) of 50% and C5‑HMF 74% for the isomerization and dehydration respectively, with a drastic reduction in reaction time and temperature. In this case, the amount of substrate processed was 50 times higher than in silent conditions.

Let A be an algebra with involution ⁎ over a field of characteristic zero. In this paper we characterize in two different ways when the multiplicities of the ⁎-cocharacter of A are bounded by a constant. As a consequence, we characterize the algebras with involution of bounded colength.

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 dibenzothiophene (DBT) in hexane. T was the sulfur compound that adsorbed the fastest on gels, and the effect of different parameters affecting the adsorption process, such as the total concentration of sulfur compounds, volume of fuel, and the contact surface area of the gel, under static or dynamic conditions, was analyzed. Bio-based polymer ILGs proved to be promising adsorbents for fuel desulfurization allowing 84% removal efficiency to be reached for T and 60% for DBT and BT in a multistage apparatus. In addition, gels could be reused up to four times without any leaching of IL or polymer in fuel, proving to be competitive with other adsorbent materials currently used.

Let V be an L-variety of associative L-algebras, i.e., algebras where a Lie algebra L acts on them by derivations, and let c(n)(L) (V), n >= 1, be its Lcodimension sequence. If V is generated by a finite-dimensional L-algebra, then such a sequence is polynomially bounded only if V does not contain UT2, the 2 x 2 upper triangular matrix algebra with trivial L-action, and UT2 epsilon where L acts on UT2 as the 1-dimensional Lie algebra spanned by the inner derivation epsilon induced by e11. In this paper we completely classify all the L-subvarieties of var(L)(UT2) and var(L)(UT2 epsilon) by giving a complete list of finite-dimensional L-algebras generating them.

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 the salts affects the characteristics of the aggregates and, in turn, their possible applications. To this aim, some interesting applications in the biomedical field are reviewed and discussed.

Let G be a finite abelian group and let A be an associative G-graded algebra over a field of characteristic zero. A central G-polynomial is a polynomial of the free associative G-graded algebra that takes central values for all graded substitutions of homogeneous elements of A. We prove the existence and the integrability of two limits called the central G-exponent and the proper central G-exponent that give a quantitative measure of the growth of the central G-polynomials and the proper central G-polynomials, respectively. Moreover, we compare them with the G-exponent of the algebra.

Let A be an associative algebra with involution ∗ over a field of characteristic zero. A central ∗-polynomial of A is a polynomial in non- commutative variables that takes central values in A. Here we prove the existence of two limits called the central ∗-exponent and the proper central ∗-exponent that give a measure of the growth of the central ∗-polynomials and proper central ∗-polynomials, respectively. Moreover, we compare them with the PI-∗-exponent of the algebra.

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 to carry out the glycolysis of PET deriving from different postconsumer waste, like opaque and colored bottles and food packages, finding that the performance is better in the former compared with the latter starting materials.

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 (ILGs) formed by 1,3-didodecylimidazolium-based salts. Temperature of gel-sol transition, morphology, response to external stimuli and rheology of hybrid ILGs (HILGs) were investigated before their use as radical scavengers. To this purpose a free radical test was performed on gels.Findings: The properties of HILGs significantly differ from the ones of pure ILGs, as CNTs appreciably improved gel rheological response. Besides, the gel network is able to enhance radical scavenging activity of both natural AOs and f-CNTs, achieving a complete radical reduction in less than 1 h. Furthermore, the activity is also preserved in thin films obtained from HILGs, opening the way to the application of these systems as material coatings. (C) 2019 Elsevier Inc. All rights reserved.

We study the differential identities of the algebra U T 2 of 2 × 2 upper triangular matrices over a field of characteristic zero. We let the Lie algebra L = Der ( U T 2 ) of derivations of U T 2 (and its universal enveloping algebra) act on it. We study the space of multilinear differential identities in n variables as a module for the symmetric group S n and we determine the decomposition of the corresponding character into irreducibles. If V is the variety of differential algebras generated by U T 2 , we prove that unlike the other cases (ordinary identities, group graded identities) V does not have almost polynomial growth. Nevertheless we exhibit a subvariety U of V having almost polynomial growth.

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 sucrose, 73% and 62%, using the relatively low temperatures of 80 and 120 °C, respectively. Interestingly, in the used experimental conditions, the solvent-catalyst systems can be reused for at least 6 cycles without loss in performance. We also investigated the dehydration of fructose under sonochemical activation, obtaining a conversion to 5-HMF of 71% in 0.5 h, at the remarkably low temperature of 40 °C.

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 nalidixic acid (NXA) alone or in combination was performed. Adsorption tests were carried out with the aim of identifying how different operational parameters, like the time of contact, the PhAC concentration, the volume of treated wastewater and the use under dynamic or static conditions, affect the removal efficiency of the soft materials investigated. Furthermore, the possibility to recycle and restore the sorbent systems for further reuse was also considered. Finally, the most efficient system was also tested in real apparatuses, like a dialysis membrane and columns. HILGs proved to be promising soft materials for addressing the target issue, revealing easy to handle sorbent systems with broad applicability in the field of environmental remediation.

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 aldol and Mannich reactions as well as Friedel Crafts or ester hydrolysis processes. Subsequently, focus is laid on metal-catalysed reactions, among which relevance is given to widely used reactions like cross-coupling and click reactions. Then, the final sections describe the use of supramolecular gels as reaction media for photo- and biocatalysed processes.

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 solvation energy relationships, while the other treats ILs as nanostructured fluids. In both cases, studies dealing with IL mixtures are also covered. Finally, literature addressing the area of supramolecular catalysis "by" or "in" ILs is also reported. This is one of the few reviews covering these specific aspects, aiming to provide a useful framework to guide future research into the effects of ILs on organic reactivity.

Hypothesis To overcome the contamination of water by heavy metals the adsorption of the pollutant on gel phases is an attractive solution since gels are inexpensive, potentially highly efficient and form a distinct phase while allowing diffusion of the contaminated water throughout the material. This work tests the chromium(VI) adsorbent capacity of new supramolecular gels for Chromium(VI) removal from wastewater. Experiments First hydrophobic imidazolium salts of carbohydrate anions were synthesised as new gelators. Subsequently, they were dissolved in a solvent by heating and, after cooling overnight, to give the formation of supramolecular gels. The properties of the resulting gels, such as thermal stability, mechanical strength, morphology, rheology, and kinetics of gel formation, were studied as a function of gelator structure, gelation solvent and pollutant removal efficiency. Findings Carbohydrate-derived gels showed the best removal capacity, i.e. 97% in 24 h. Interestingly, in one case, the reduction of chromium(VI) to chromium(III) also occurred after the adsorption process, and this phenomenon has been analysed using 1H NMR spectroscopy, IR spectroscopy, and SEM. The most efficient gel can reach an adsorption capacity of 598 mg/g in contrast to a value of 153 mg/g for the most effectively best hydrogels reported to date. The new gel can be also recycled up to 4 times. These findings suggest that these new, supramolecular hydrogels have potential applications in environmental remediation.

The cathodic reduction of dicationic imidazolium bromides, whose spacer is either an aliphatic chain or a xylyl group, leads to the formation of the corresponding N-heterocyclic carbenes (NHCs), which were isolated as the corresponding thiones, after reaction with elemental sulfur. The behaviour of the dications was compared with the corresponding monocations. The behaviour of dicarbenes depends on the nature of the spacer. This study evidenced that dicarbenes deriving from xylyl dications are less stable than the corresponding aliphatic ones (giving lower yields in thiones), due to a debenzylation reaction. On the other hand, the yields in thiones starting from aliphatic dications are higher than the corresponding monocations, suggesting a cooperative reduction at the electrode of the two imidazolium moieties. The cathodic process was confirmed using the co-electrogenerated hydrogen to reduce 2,2,2- trifluoroacetophenone to the corresponding alcohol.

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 physiological stimuli. In addition, the biodegradability and biocompatibility allowed the use of supramolecular gels also for cancer diagnosis, as they can be facilely endocytosed into cells [1]. Remembering the good biological response of some imidazolium derived hydrogels [2], fluorescent imidazolium organic salts, that should own the double function of gelator and bioimaging agent, have been synthesized. New fluorescent hydrogels with interesting physico-chemical properties (rheology, gel-sol temperature transition and optical properties) have been tested for anti-proliferative activity, in vitro bioimaging on cancer cells and controlled release of gelator in physiological medium. Results evidence how these hydrogels can be potentially investigated as new theranostic media for anticancer research

In this paper we study the growth of the differential identities of some algebras with derivations, i.e., associative algebras where a Lie algebra L (and its universal enveloping algebra U(L)) acts on them by derivations. In particular, we study in detail the differential identities and the cocharacter sequences of some algebras whose sequence of differential codimensions has polynomial growth. Moreover, we shall give a complete description of the differential identities of the algebra UT2 of 2 × 2 upper triangular matrices endowed with all possible action of a Lie algebra by derivations. Finally, we present the structure of the differential identities of the infinite dimensional Grassmann G with respect to the action of a finite dimensional Lie algebra L of inner derivations.

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 least 9 times without losing efficiency, also with dye mixtures. Interestingly, this gel can be loaded onto columns to decolorize flowing solutions, achieving 85 % of removal efficiency in only 10 minutes and allowing its reuse for at least 4 cycles. In terms of adsorption capacity, this eutectogel is competitive with efficient gel-based dye sorbent systems, with a value 1930 mg/g reached at a high concentration of rhodamine B 479 mg/L.

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 were analyzed. Imidazolium salts were successfully tested for their possible application as bioimaging and cytotoxic agents toward three cancer cell lines and a nontumoral epithelial cell line. Characterization of their behavior was performed by MTT and cell-based assays. Finally, the biological activity of hydrogels was also investigated. Collectively, our findings showed that naphthalimide-based imidazolium salts are promising theranostic agents and they were able to preserve their biological properties also in the gel phase.

Let G be the infinite dimensional Grassmann algebra over an infinite field F of characteristic different from two. In this paper we study the differential identities of G with respect to the action of a finite dimensional Lie algebra L of inner derivations. We explicitly determine a set of generators of the ideal of differential identities of G. Also in case F is of characteristic zero, we study the space of multilinear differential identities in n variables as a module for the symmetric group Sn and we compute the decomposition of the corresponding character into irreducibles. Finally, we prove that unlike the ordinary case the variety of differential algebras with L action generated by G has no almost polynomial growth.

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. Interestingly, soft materials can be reused for at least 20 cycles, partially regenerated, and reused for further 15 cycles. Comparison with data previously reported in the literature shows that this is a prerogative of this system and this represents not only an improvement but also a warranty of low raw material production after wastewater treatment.

Hybrid diimidazolium-based ionogels were obtained by dispersing nitrogen-doped carbon nanodots (NCNDs) in ionic liquid (IL) solutions and by using dicationic organic salts as gelators. The properties of the NCND-ionogels were studied in terms of thermal stability, mechanical strength, morphology, rheological, and microscopic analyses. Insights into the formation of the hybrid soft material were attained from kinetics of sol-gel phase transition and from estimating the size of the aggregates, obtained from opacity and resonance light-scattering measurements. We demonstrate that, on one hand, NCNDs were able to favor the gel formation both in the presence of gelating and nongelating ILs. On the other hand, the gelatinous matrix retains and, in some cases, improves the properties of NCNDs. The NCND-ionogels showed the typical fluorescence emission of the carbon dots and a notable antiradical activity, with higher efficiency as compared to the single components. The presented hybrid materials hold great promise for topical applications in antioxidant fields.

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, physical properties of gels, such as the temperature of the gel&ndash, sol transition, morphology, and rheology, have been studied for their use as sorbents. These properties influence the gel removal efficiency of PhAC, i.e., the best system is the gel that presents weaker colloidal forces. A fast removal (RE = 51%) is obtained in 3 h for ciprofloxacin, while a slower adsorption process is observed for nalidixic acid (RE = 88% in 24 h). HILGs can be recycled up to seven cycles and regenerated. In addition, they can be used with higher concentrations or volumes of PhAC and in a realistic apparatus like dialysis membranes. These peculiarities suggest that HILGs can be competitive with more complex sorbent systems.

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.e., temperature and time. The different components of the system differently influence the reaction outcome, and to understand the interactions existing among them, 1 H NMR investigation was carried out. In general, the nonconventional reaction media demonstrated better performance than conventional ones, applying only a small amount of solvent. Good results in terms of yield and enantiomeric excess have been obtained in ionic liquid gels that seem promising media in the catalytic field. Furthermore, to the best of our knowledge, this is one of the first examples for the study of asymmetric alcoholysis of anhydrides in ionic liquid solution and gel phase.

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 conditions. Indeed, at 60 °C and in the presence of 20 mol % of catalyst, 5-HMF yields of 60 and 30 % were obtained from fructose and sucrose, respectively. The catalytic system was recycled and used up to six times observing no appreciable loss in yield for the first four cycles. Moreover, we gathered mechanistic information by in situ 1H NMR monitoring the dehydration of fructose. To dissect the role of acidity on the reaction, we determined the Hammett acidity function of each salt. Comparison of these results with yields and reactivity observed in the presence of related monocationic salts and with a dicationic salt bearing only one sulfonic acid group allowed stating that the reactivity observed is the result of the combined action of acidity and structural features of the catalysts. Overall, the approach proposed here could contribute to pave the way to increase sustainability in the raw material valorization processes.

Let $A$ be an associative algebra over a field $F$ of characteristic zero and let $L$ be a Lie algebra over $F$. If $L$ acts on $A$ by derivations, then such an action determines an action of its universal enveloping algebra $U(L)$ and in this case we refer to $A$ as algebra with derivations or $L$-algebra. Here we give a characterization of the ideal of differential identities of finite dimensional $L$-algebras $A$ in case the corresponding sequence of differential codimensions $c_n^L (A)$, $n\geq 1$, is polynomially bounded. As a consequence, we also characterize $L$-algebras with multiplicities of the differential cocharacter bounded by a constant.

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 conventional solvents and ionic liquids, leading to aggregation induced emission processes. Notably, emission was maintained also in the solid state, with higher or lower intensity compared with the solution, depending on which spacer is present. This latter, also impacts on the morphology of the aggregates, allowing fine tuning the properties of the supramolecular materials formed.

Insights are provided into the properties of molecular gels formed by diimidazolium salts both in “normal” solvents and ionic liquids. These materials can be interesting for applications in green and sustainable chemistry in which ionic liquids play a significant role, like catalysis and energy. In particular, two positional isomers of a diimidazolium cation have been examined with a wide range of anions for their ability to form gel phases. In particular, di-, tri-, and tetravalent anions bearing aliphatic or aromatic spacers were paired with the divalent cations. The properties of the organo- and ionogels formed have been analyzed by means of several different techniques, including calorimetry, rheology, resonance light scattering, UV/Vis absorption, polarizing optical microscopy, and powder X-ray diffraction measurements. The investigations performed enabled us to obtain a wide range of conductive materials characterized by a high thermal stability and a low corrosiveness of the gelator (organogels) or of both gelator and solvent (ionogels). The information gained should be useful in the broader quest to identify and promote their applications.

The catalytic ability of some functionalised diimidazolium ionic liquids was tested using the Michael addition of malononitrile to t-chalcone as probe reaction. Diimidazolium salts characterized by the presence of 1-(1-imidazolylmethyl)-3,5-di-[1-(3-octylimidazolylmethyl)]benzene cation and differing in the anion structure were used. Both mono- and dianions were employed and among these some chiral anions generally used as organocatalysts were taken into account. Data collected were analysed both as function of ionic liquids structure and basicity, evaluated using the Hammett basicity function. Although the use of chiral anions did not allow performing a stereochemical control of the reaction, data collected demonstrate the high catalytic ability of the functionalised salts. Indeed, high conversions and yields were obtained under mild conditions and in significantly shorter reaction times with respect to the ones so far reported for this reaction.

Diimidazolium-based organic salts, bearing peptides or amino acids as anions have been synthesised and tested for their gelling ability in biocompatible solvents. These low molecular weight salts were successfully used as gelators in phosphate buffered saline (PBS) solution and ionic liquids. Then, the properties of the obtained soft materials were analysed in terms of melting temperature and gel strength as accounted for by rheological investigations. The gel-phase formation was studied by using UV/Vis and resonance light scattering measurements, whereas the morphology of the soft materials was analysed by using polarised optical microscopy and scanning electron microscopy. To get information about the organisation of the gelator in the gelatinous matrix, X-ray diffraction measurements were performed both on the neat gelators and their gels. The results collected show that the properties of the gel phases, like the thermal stability, the self-repairing ability, the resistance to flow as well as the morphology, are dependent on the nature of the anion. Furthermore, bioassays revealed that the obtained diimidazolium organic salts possessed antimicrobial activity, against gram-negative and gram-positive tester strains. In particular and noteworthy, the diimidazolium organic salts exert a bactericidal capability, which was retained even if they are included in the gel phase. Thus, a novel kind of bioactive soft material was obtained that could be fruitfully employed as a non-covalent coating exerting antibacterial capability.

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 DFT calculations. Data collected show that the complex stability is heavily affected by solvent nature. Furthermore, solvent being the same, it increases with the decrease of the alkyl chain length and the anion coordination ability. The joint information obtained from 1H NMR and DFT calculations allows drawing a picture of the complex geometry. On the other hand, fluorescence investigation on the solid state evidences the occurrence of an aggregation enhanced emission process for these systems.

Diimidazolium and dipyrrolidinium organic salts were tested for their ability to gel both organic solvents and ionic liquids. Organic salts containing 1-(1-imidazolylmethyl)-3,5-di-(3'-octylimidazolylmethyl)-benzene and 1-(N-pyrrolidylmethyl)-3,5-di-(N,N-octylpyrrolidylmethyl)-benzene cations were used. In addition to the simple bromide anion, also dianions having a naphthalene core such as 1,5- and 2,6-naphthalenedisulfonate and 2,6-naphthalenedicarboxylate were taken into account. Gelation tests demonstrated that organic salts used were able to harden ionic liquids. The materials obtained were investigated for their thermal stability and also for electric conductivity properties using micro-DSC and dielectric spectroscopy. Furthermore, the opacity of some gel phases was monitored using UV-vis measurements. To obtain information about the gelation mechanism, gel phase formation was studied as a function of time by means of resonance light scattering investigation. Finally, the ability of materials to respond to external stimuli such as magnetic stirring or ultrasound irradiation was also analyzed. Data collected show that different relationships exist among the gelator and the ionic liquid structure, determining the properties of materials and their possible applications.

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. Furthermore, to have information about the effect deriving from the spacer rigidity also dianions such as 1,4-butanedicarboxylate and 1,6-hexanedicarboxylate were used. The basic strength of dicationic ionic liquids was determined using the Hammett indicator method. Data collected gave evidence that the outcome of the target reaction was affected by the nature of interactions operating between cation and anion of the ionic liquid used. Quite interestingly, solvent systems used had a good recyclability. Indeed, in some cases, they were reused for four cycles without significant loss in yield.

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 ]). Carbohydrate conversion in [bmim][BF 4 ]/[bmim][Cl] binary mixtures, has been studied under both magnetic stirring and ultrasound (US) activation. The catalytic system used led to the formation of 5-hydroxymethylfurfural in good yield under mild conditions. A significant influence of IL binary mixture composition on the outcome of the target processes was evidenced. Improvements in both reaction time and temperature have been observed, under US activation.

In order to reveal the possible formation of free N-heterocyclic carbene (NHC) in DMF-azolium and acetate solutions, the proton exchange equilibrium between azolium cations and CH3COO− was investigated (by cyclic voltammetry) by adding CH3COOH or tetrabutylammonium acetate to DMF solutions of imidazolium or thiazolium salts of different acidity.The voltammetric analysis confirms that the deprotonation of the azolium cation by CH3COO− (with the formation of free NHC) is significant in the case of the more acidic thiazolium cations, while it is not effective with the less acidic imidazolium ones.Accordingly, the NHC-catalyzed benzoin condensation was carried out in DMF solutions of azolium salts, tetrabutylammonium acetate, and benzaldehyde. Benzoin was isolated only starting from the more acidic thiazolium salts. Keywords: Cyclic voltammetry, NHC, Azolium salts, Tetrabutylammonium acetate, Acetic acid, Benzoin condensation

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 significant reduction in energy consumption as compared to the reaction conducted under magnetic stirring.

Background Paroxetine is the most potent inhibitor of the reuptake of serotonin of all selective serotonin reuptake inhibitors (SSRIs) and has been studied in many randomised controlled trials (RCTs). However, these comparative studies provided contrasting findings and systematic reviews of RCTs have always considered the SSRIs as a group, and evidence applicable to this group of drugs might not be applicable to paroxetine alone. The present systematic review assessed the efficacy and tolerability profile of paroxetine in comparison with tricyclics (TCAs), SSRIs and newer or non-conventional agents. Objectives 1. To determine the efficacy of paroxetine in comparison with other anti-depressive agents in alleviating the acute symptoms of Major Depressive Disorder. 2. To review acceptability of treatment with paroxetine in comparison with other anti-depressive agents. 3. To investigate the adverse effects of paroxetine in comparison with other anti-depressive agents. Search methods We searched the Cochrane Depression, Anxiety and Neurosis Review Group's Specialized Register (CCDANCTR, to 30 September 2012), which includes relevant randomised controlled trials from the following bibliographic databases: The Cochrane Library (all years), EMBASE (1974 to date), MEDLINE (1950 to date) and PsycINFO (1967 to date). Reference lists of relevant papers and previous systematic reviews were handsearched. Pharmaceutical companies marketing paroxetine and experts in this field were contacted for supplemental data. Selection criteria All randomised controlled trials allocating participants with major depression to paroxetine versus any other antidepressants (ADs), both conventional (such as TCAs, SSRIs) and newer or non-conventional (such as hypericum). For trials which had a cross-over design, only results from the first randomisation period were considered. Data collection and analysis Two review authors independently checked eligibility and extracted data using a standard form. Data were then entered in RevMan 5.2 with a double-entry procedure. Information extracted included study and participant characteristics, intervention details, settings and efficacy, acceptability and tolerability measures. Main results A total of 115 randomised controlled trials (26,134 participants) were included. In 54 studies paroxetine was compared with older ADs, in 21 studies with another SSRI, and in 40 studies with a newer or non-conventional antidepressant other than SSRIs. For the primary outcome (patients who responded to treatment), paroxetine was more effective than reboxetine at increasing patients who responded early to treatment (Odds Ratio (OR): 0.66, 95% Confidence Interval (CI) 0.50 to 0.87, number needed to treat to provide benefit (NNTb) = 16, 95% CI 10 to 50, at one to four weeks, 3 RCTs, 1375 participants, moderate quality of evidence), and less effective than mirtazapine (OR: 2.39, 95% CI 1.42 to 4.02, NNTb = 8, 95% CI 5 to 14, at one to four weeks, 3 RCTs, 726 participants, moderate quality of evidence). Paroxetine was less effective than citalopram in improving response to treatment (OR: 1.54, 95% CI 1.04 to 2.28, NNTb = 9, 95% CI 5 to 102, at six to 12 weeks, 1 RCT, 406 participants, moderate quality of evidence). We found no clear evidence that paroxetine was more or less effective compared with other antidepressants at increasing response to treatment at acute (six to 12 weeks), early (one to four weeks), or longer term follow-up (four to six months). Paroxetine was associated with a lower rate of adverse events than amitriptyline, imipramine and older ADs as a class, but was less well tolerated than agomelatine and hypericum. Included studies were generally at unclear or high risk of bias due to poor reporting of allocation concealment and blinding of outcome assessment, and incomplete reporting of outcomes. Authors' conclusions Some possibly clinically meaningful differences between paroxetine and other ADs exist, but no definitive conclusions can be drawn from these findings. In terms of response, there was a moderate quality of evidence that citalopram was better than paroxetine in the acute phase (six to 12 weeks), although only one study contributed data. In terms of early response to treatment (one to four weeks) there was moderate quality of evidence that mirtazapine was better than paroxetine and that paroxetine was better than reboxetine. However there was no clear evidence that paroxetine was better or worse compared with other antidepressants at increasing response to treatment at any time point. Even if some differences were identified, the findings from this review are better thought as hypothesis forming rather than hypothesis testing and it would be reassuring to see the conclusions replicated in future trials. Finally, most of included studies were at unclear or high risk of bias, and were sponsored by the drug industry. The potential for overestimation of treatment effect due to sponsorship bias should be borne in mind.

A new class of functionalised dicationic ionic liquids, containing a central cationic unit capped by a basic functionality (imidazole), has been synthesised. These salts have been characterised in isotropic solution using proton and 2D-NMR spectroscopy, and their thermal stability has been studied by DSC and TGA. All these novel salts contain the 1-(1-imidazolylmethyl)-3,5-di{1-(3'-octylimidazolylmethyl)}-benzene cation as a defining structural motif. Salts of both singly and doubly charged anions were prepared and, in particular, the selected monoanions (Br(-), [BF4](-), or [NTf2](-)) differ in size, shape and hydrogen-bonding ability, whereas the dianions differ in the nature of the spacer, such as 1,4-benzenedicarboxylate, 2,6-naphthalenedicarboxylate, 1,5- and 2,6-naphthalenedisulfonate, 1,4-butanedicarboxylate, and 1,6-hexanedicarboxylate. These ionic liquids exhibit the presence of different conformers in solution, whose distribution is affected by the nature of the anion. The nature of the anion also affects their thermal stability.