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Two requirements of a porous filler for Mixed Matrix Membranes [MMMs] are a good adhesion to the polymer and the openness of its pores. The surface of SAPO-34 has been grafted with moieties containing amino groups, aromatic rings, and fluorinated chains, for a good adhesion to glassy polyimides, aromatic polymers and perfluoropolymers. The controlled excess of the modification agent – preferably trichlorosilanes – in hydrophobic solvents and the strict control of moisture in the reaction environment prevent the growth of thick layers of grafts around the crystals. XPS confirms the success of the derivatizations and indicates a homogeneous and thin coverage of the surface. The negligible reduction of the surface area suggests that the modification of the surface does not plug the micropores. The counter-intuitive faster adsorption of n-heptane in silicalite-1 after modification with bulky fluorinated grafts indicates the openness of the pores even for large molecules, and the reduction of the resistance to the transport of mass across the surface of the molecular sieves, thanks to the reduced amount of water adsorbed on the hydrophobic outer surface of the crystals.

A series of ketonitrones derived from isatin and indanone (INs) were synthesized and evaluated for their antiproliferative activities against several human cancer cell lines. Then, the antioxidant properties of these substrates were measured by the DPPH test to report their biological activity in terms of their spin trapping action. In particular, one substrate has showed very high biological and scavenging activity, probably due to the strong correlation between its spin trapping activity and structure.

A simple procedure to obtain 1,5-disubstituted 1,2,3-triazoles, using the Er(OTf)3/[mpy]OTf/H2O catalytic system is described. The reaction proceeds through an eliminative azide–olefin cycloaddition (EAOC) offering a highly regioselective approach and good yields (81–94%). The advantages of this method include simple operations of work-up and the ability of the catalytic system to be re-used five times without an evident loss in yield. The role of IL and water were speculated, invoking also a probable ionic self-assembly (ISA) effect.

Stoichiometric triethylamine in methanol produces sub-micron ZIF-90 in 98% yield with the largest gas uptakes ever measured. Micropore volume and surface area are compatible with an empty pore network and with crystallographic data, but the occurrence of crystal defects, such as missing ligands or Zn2+ ions, although improbable, can not be ruled out.

A simple procedure to obtain 1,5-disubstituted 1,2,3-triazoles, using the catalytic system erbium(III) trifluoromethanesulfonate, 1-methyl pyridinium trifluoromethanesulfonate and water is described. The reaction proceeds through an eliminative azide–olefin cycloaddition (EAOC) offering a highly regioselective approach and good yields (81–94%). The advantages of this method include simple operations of work-up and the ability of the catalytic system to be re-used five times without an evident loss in yield.

The good affinity of TiO2 surface for hydrogen sorption has prompted in the past the synthesis of high specific surface area, Ti-doped mesoporous silicas. Since most TiO2 is buried in the pore walls of the silicas, such materials did not express their full potential H2 uptake. In order to overcome this limitation, different amounts of titania were deposited on the pore surface of a pre-formed SBA-15 of 704 m2/g, and the resulting oxides were calcined at 300 or 500 °C. The hydrogen sorption–desorption isotherms of the materials prepared in this study, at 77.4 K and up to 100 kPa, reveal that a small amount of titania doubles the hydrogen storage capacity of SBA-15, provided that the materials are calcined at least at 300 °C. Reproducible H2 uptakes up to 1.4 wt.% at 77.4 K and 100 kPa have been measured. The optimal amount of TiO2 is 4.5% in moles, leading to a uniform dispersion in the mesopores. A higher loading (7.3%) brings about the formation of large titania particles that tend to block the lumen of the mesopores, with no gain in the H2 sorption capacity.

Under a Creative Commons license., A library of C-alkyl and C-aryl nitrones has been obtained by direct condensation of primary N-substituted hydroxylamine hydrochlorides with various aldehydes and ketones without catalysts or base. The synthetic procedure, performed under MW irradiation in the absence of solvent, does not require the presence of a base, is fast, clean, high-yielding and characterized by simple work-up.

Efficient one-pot three component reaction of aniline derivatives with cyanoamide and triethyl orthoformate at reflux in toluene affords N′-aryl-N-cyanoformamidines in high yields just by the distillation of the azeotrope toluene/ethyl alcohol. Labelled d9-Amitraz is prepared by the application of this procedure in the synthesis of formamidine pesticides family.

An efficient, eco-compatible, and very cheap method for the construction of triazoles via eliminative azide&ndash, olefin cycloaddition (EAOC) reaction has been developed by a catalytic system, IL/FeCl3, offering a highly regioselective approach to structurally diverse 1,5-disubstituted 1,2,3-triazoles in up to 95% yield. This strategy features the reuse of a catalytic system through simple operations. Mechanistic studies indicated that an asynchronous concerted dipolar cycloaddition&ndash, elimination process might be involved.

Nucleobase-containing isoxazolidines spiro-bonded to an indane core have been synthesized in very good yields by regio- and diastereoselective 1,3-dipolar cycloaddition starting from indanyl nitrones and N-vinylnucleobases by using environmentally benign microwave technology. The contemporary presence of various structural groups that are individually active scaffolds of different typology of drugs, has directed us to speculate that these compounds may act as inhibitors of MDM2-p53 interaction. Therefore, both computational calculations and antiproliferative screening against A549 human lung adenocarcinoma cells and human SH-SY5Y neuroblastoma cells were carried out to support this hypothesis., We thank the Italian Ministry of University and Scientific Research (MIUR) for a doctoral grant and the University of Calabria for financial support. We also acknowledge the MINECO and FEDER Program (Madrid, Spain, project CTQ2016-76155-R) and the Gobierno de Aragon (Zaragoza, Spain. Biological & Computational Chemistry Group. E34_R17).

The efficiency of Er(OTf) 3 in promoting the Diels–Alder reactions between different dienes and dienophiles in ionic liquids has been investigated. Compared with the analogous cycloadditions performed in conventional solvents shorter reaction times are required to obtain good/excellent yields. In most cases an enhancement of regio- and endo:exo selectivity was observed. The role of the ionic liquid, as a function of the cationic part, i.e. the imidazolium based or the pyridinium based, is discussed well. The ILs containing the catalyst can be readily separated from the reaction products and recovered in very high purity for direct reuse, up to six cycles.

1,3-Dipolar cycloadditions of nitrones with alkenes afforded the corresponding isoxazolidines in ionic liquids in the presence of Er(OTf)3. The ionic liquid and the catalyst are recycled up to five times without any specific treatment or loss of activity. Extension of the procedure to the synthesis of isoxazolidinyl nucleosides has been investigated.

This work was supported by the Ministerio de Ciencia e Innovacion (MICINN) and FEDER Program (Madrid, Spain, project CTQ2013-44367-C2-1-P) and the Gobierno de Aragon (Zaragoza, Spain. D.R.-L. thanks the Spanish Ministry of Education (MEC) for a pre-doctoral grant (FPU program). We thank the Italian Ministry of University and Scientific Research (MIUR) for a doctoral grant and the University of Calabria for financial support.

The synthesis, characterization and evaluation of a new highly efficient organocatalyst, namely (5S)-2,2,3-trimethyl-5-thiobenzylmethyl-4-imidazolidinone hydrochloride has been achieved. The catalyst possesses important structural features that should increase the catalytic efficiency and solubility in polar media. The application of ionic liquid-supported imidazolidinone catalyst in enantioselective Diels–Alder reactions was investigated. The Diels–Alder reactions of several dienes and dienophiles proceeded efficiently in the presence of the catalyst to provide the desired products in a range from moderate to good yields and from good to excellent enantioselectivities. The conformational study confirms that in the transition state the Re face is completely shielded by phenyl ring preferring approach on less hindered Si face. Particularly remarkable is the fact that the entire system IL/HCl 0.01 M/Catalyst can be recovered and reused for up to six runs without appreciable loss of catalytic activity., This work was supported by the Ministerio de Ciencia e Innovación (MICINN) and FEDER Program (Madrid, Spain, project CTQ2013-44367-C2-1-P) and the Gobierno de Aragón (Zaragoza, Spain. D.R.-L. thanks the Spanish Ministry of Education (MEC) for a pre-doctoral grant (FPU program). We thank the Italian Ministry of University and Scientific Research (MIUR) for a doctoral grant and the University of Calabria for financial support.

Er(OTf)3 was found to be an effective Lewis acid catalyst for the conversion of aldehydes into acylals. Unlike most of the other known catalysts, it is able to give acylals from acetic anhydride as well as other anhydrides. Moreover, it can react with cyclic ketones to give unstable acylals, which can be isolated as enol esters. Other advantages are the very low loading of catalyst, excellent chemoselectivity, and solvent-free and mild conditions.

Erbium triflate is able to afford vic-diacetates in better yields, lower catalyst amounts and shorter times than most of the reported methods. Therefore, the present procedure represents a valuable, general and environmentally benign procedure to prepare these compounds.

Er(OTf) 3 is a useful catalyst for the Ferrier rearrangement furnishing high yields of products, cleaner reaction profiles, short reaction times, mild reaction conditions, high stereoselectivity and recoverability of the catalyst which is also commercially available.

Aldimines, ketimines, and enaminones can be obtained under erbium(III) triflate catalysis. The reaction mechanism is that typical of imine synthesis. The role of the catalyst is demonstrated for the synthesis of aromatic imines. In contrast to CeCl 3 /NaI addition to unsaturated aldehydes, which results in Michael addition, no Michael adduct was observed under erbium(III) triflate catalysis.

Epoxides dissolved in acetone can be converted almost quantitatively in acetonides in the presence of catalytic amounts of erbium(III) triflate. The procedure can be usefully applied to other substrates and can be extended to other ketones.

Erbium(III) triflate is a powerful catalyst for the acylation of alcohols and phenols. The reaction works well for a large variety of simple and functionalized substrates by using different kinds of acidic anhydrides {Ac2O, (EtCO)2O, [(CH3)3CO]2O, Bz2O, and (CF3CO)2O} without isomerisation of chiral centres. Moreover, the catalyst can be easily recycled and reused without significant loss of activity.

Several bisphosphonate esters (III) bearing a substituted isoxazolidine moiety are synthesized in the absence of any solvent in good yields and short reaction times.

The MacMillan iminium catalyst was investigated for asymmetric Diels–Alder cycloadditions in ionic liquid/H2O homogeneous phase. Superior selectivity, product yield, and shorter reaction times were observed in comparison with classical organic solvents. Additional advantages are the easy synthetic procedure, the excellent recovery of products, and the recyclability of the whole system.

The MacMillan iminium catalyst was investigated for asymmetric Diels–Alder cycloadditions in ionic liquid/H2O homogeneous phase. Superior selectivity, product yield, and shorter reaction times were observed in comparison with classical organic solvents. Additional advantages are the easy synthetic procedure, the excellent recovery of products, and the recyclability of the whole system.

Oxidation of nitro-derivatives in ionic liquids using basic hydrogen peroxide or sodium perborate provides a mild and efficient alternative to the traditional Nef reaction.

Basic hydrogen peroxide and sodium perborate were found to be cheap and efficient alternatives for the conversion of primary and secondary nitro to carbonyl compounds (Nef reaction) in ionic liquids.

1,3-Dipolar cycloadditions of nitrones with alkenes afforded the corresponding isoxazolidines in ionic liquids in the presence of Er(OTf)3. The ionic liquid and the catalyst are recycled up to five times without any specific treatment or loss of activity. Extension of the procedure to the synthesis of isoxazolidinyl nucleosides has been investigated.

Er(OTf)3 is a useful catalyst for the Ferrier rearrangement furnishing high yields of O- and S-glycosides. The transformation has wide applicability, cleaner reaction profiles, mild reaction conditions, and high stereoselectivity and the catalyst, which is also commercially available, can be recovered and reused.

Er(OTf) 3 is a useful catalyst for the Ferrier rearrangement furnishing 2',3'-dideoxy pyranosyl nucleosides easily by means of cleaner reaction profiles, short reaction times, mild reaction conditions, good stereoselectivity, and good recoverability of the commercially available catalyst.

Er(OTf) 3 is a useful catalyst for the Ferrier rearrangement furnishing high yields of products, cleaner reaction profiles, short reaction times, mild reaction conditions, high stereoselectivity and recoverability of the catalyst which is also commercially available.

A preliminary library of modified N,O-nucleosides was prepared and tested on a selected number of human cancer lines that include SKOV3, SW480, and K562. Thymine, N-benzyl substituents, and aromatic rings contribute to an increase of the biological activity, up to 10–25 μM, that appeared also reliant on the calculated lipophilicity of the nucleosides, expressed as cLogP, where P represents the partition coefficient of a solute between n-octanol and water.

Erbium(iii) chloride is a powerful catalyst for the acylation of alcohols and phenols. The reaction works well for a large variety of simple and functionalized substrates by using different kinds of acidic anhydrides (Ac2O, (EtCO)2O, (PriCO)2O, (ButCO)2O, and (CF3CO)2), without isomerization of chiral centres. Moreover, the catalyst can be easily recycled and reused without significant loss of activity.