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Biopolymer electrolytes based on iota-carrageenan (I-carrageenan) with sodium trifluoromethanesulfonate (NaTf) were prepared by way of the conventional solution-casting technique. The biopolymer I-carrageenan was fixed as 1 g, and the concentration of NaTf was varied from 0.1 to 0.5 wt% in steps of 0.1 wt%. Distilled water was used as a solvent. Alternating current (AC) impedance measurements were carried out in the frequency window of 42 Hz–1 MHz. The same measurements were also carried out at different temperatures for all the prepared biopolymer samples. A maximum ionic conductivity of 2.6771 × 10−5 S/cm was obtained for the 0.3 wt% NaTf-added I-carrageenan system at room temperature. The temperature-dependent conductivity plot of the polymer electrolyte seemed to obey the Arrhenius relation. A low activation energy of 0.021 eV was observed for the sample with the highest ionic conductivity. From AC impedance data, dielectric parameters were obtained. The magnitude of the dielectric constant was found to increase with the increase in temperature. A low relaxation time was observed for the sample that possesses the maximum ionic conductivity.

Highly chemo- and regio-selective C-H bond functionalization of unactivated arenes with propargyl α-aryl-α-diazoacetates has been developed using scandium catalysis. A variety of unactivated, mildly deactivated, and electronically activated arenes have been functionalized using this protocol. The synergistic combination of scandium triflate as a catalyst and propargyl α-aryl-α-diazoacetate as a reagent played a pivotal role in the effective C-H bond functionalization of arenes without the assistance of any directing group or ligand. The practicality of the protocol has been demonstrated by the gram-scale synthesis of very useful α,α-diarylacetates including antispasmodic drug-adiphenine. Based on the experimental observations, labeling experiment, and density functional theory calculations, a plausible reaction mechanism has been outlined.

The main advantages of the use of ionic liquids in enhanced oil recovery are their tunability and stability in harsh environmental conditions. In this work, a comprehensive review of ionic liquids proposed to improve current chemical oil recovery methods has been presented, focusing on core flooding experiments. With an almost infinite number of possible ionic liquids, the amount of experiments carried out up to now has been very limited. However, results are promising, with additional recovery after secondary flooding of up to 32% of the original oil in place. Most formulations with ionic liquids have been proposed for sandstone reservoirs, the number of studies with carbonate cores being very scarce. The possibilities of a new room temperature surface active ionic liquid, 1-decyl-3-methylimidazolium triflate, for this application were analyzed. It was shown that it is able to drastically reduce the water/oil interfacial tension. An optimized formulation was proposed for carbonate reservoirs. After secondary flooding with brine, an additional recovery of 10.5% of original oil in place was achieved at room conditions. A combination of the proposed method followed by a polymer flooding step with polyacrylamide led to a lesser but still significant recovery, reducing the costs associated to the ionic liquid.

The development of a conventional electrolyte, based on commercially available magnesium (Mg) salts in organic solvents, remains one of the most challenging quests for rechargeable Mg batteries. Conventional electrolytes typically form a passivation layer on Mg metal anode, necessitating the extensive use of inorganic chloride additives such as MgCl2. Herein, for the first time, we introduce an organic chloride, tetrabutylammonium chloride (TBAC), as a multifunctional electrolyte additive for conventional magnesium triflate (Mg(OTf)2)-based electrolytes. TBAC was found to perform three major roles: (1) enhance Mg(OTf)2 dissociation in aprotic solvent, (2) inhibit the reduction of triflate anions through surface-adsorbed TBA+, and (3) act as a chloride source to form Mg complexes and stabilize the Mg anode-electrolyte interface. The novel electrolyte combination of TBAC and Mg(OTf)2 in 1,2-dimethoxyethane exhibits excellent Mg plating/stripping with Coulombic efficiency of 97.7% over 200 cycles at 0.5 mA cm−2 and 0.5 mAh cm-2. Post-mortem analysis unveils uniform Mg deposition and stable solid electrolyte interphase formation on Mg anode, which enables reversible cycling with Mo6S8 cathode. Together with our findings on another organic chloride additive, 1-ethyl-3-methylimidazolium chloride, and in combination with different electrolyte salts and solvents, we showcase the general promise of high-performance conventional electrolytes for rechargeable Mg batteries.

Background:: Dihydroquinazolinone derivatives are an important family of fused heterocyclic shows a wide range of biological, medicinal and pharmacological properties such as anti-tumor, anti-biotic, diuretic, analgesic, antihypertonic, anti-pyretic, anti-depressant, anti-histamine and vasodilation activities. Introduction:: So far some acid catalysts, e.g.; p-toluenesulfonic acid, silica sulfuric acid, zinc(II) perfluorooctanoate, gallium(III) triflate, ionic liquid, Al(H2PO4)3, I2, montmorillonite K-10, Amberlyst-15, Al/Al2O3 and Fe3O4 nanoparticles, have been reported to accomplish this three component reaction. Some of these methods have drawbacks such as toxic solvents and catalysts, long reaction time, the use of expensive catalysts and adverse yields. Method:: A mixture of benzaldehydes (1mmol), isatoic anhydride (1 mmol), Glycine (1 mmol) and OImDSA (2 mL) were stirred at room temperature for the required reaction times (1-2 h). The progress of the reaction was monitored by TLC (EtOAc: petroleum ether 1:2). After completion of reaction, as indicated by TLC, the ionic liquid was separated by extraction with 2×15 mL of water. The solid residue was separated by recrystallization from EtOH. The pure products were collected in 86-97% yields. Results:: Herein, in order to achieve a more efficient synthesis method, to deplete side effects, reduce reaction steps, increase efficiency and curtail reaction time, and also to continue our research on the synthesis of heterocyclic and pharmaceutical compounds. We wish to report the mild synthesis of some derivatives of 2-aryl-quinazolin-4(1H)-ones from isatoic anhydride and Glycine using OImDSA Conclusion:: In conclusion, we have developed a simple, green and efficient protocol for the synthesis of 2-aryl-quinazolin- 4(1H)-ones using OImDSA as an efficient and new procedure. Simplicity, easy practice, integrated with inexpensive, environmentally friendly and reusable ionic liquid are notable attributes of this new method. To the best of our knowledge, this is the first report for the synthesis of a new library of quinazolin-4(1H)-ones derived from Glycine as a natural substrate based on green chemistry conditions.

The green macroalga Ulva rigida represents a promising feedstock for biorefinary due to its fast growth and cosmopolitan distribution. The main component of the cell walls of U. rigida is a sulfated glucuronorhamnan polysaccharide known as ulvan. Herein it was found that due to the high (hydrogen)sulfate group content of ulvan, hydrothermal autohydrolysis at 130 °C renders a high percentage of rhamnose (78–79 % recovery from the initial content in the raw material), a rare sugar of high added value. In addition, acid catalysis by a triflate-based graphene oxide under oxygen-free conditions at 180 °C affords moderate amounts of tartaric acid (24–26 %). The same triflate-based graphene oxide catalyst under oxygen pressure yields remarkably high percentages of succinic acid (65 %). The catalyst preserves its activity for at least five consecutive reuses., Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa SEV2016-0683, RTI2018-890237-CO2-R1) and Generalitat Valenciana (Prometeo 2017−083) is gratefully acknowledged. Vasile I. Parvulescu kindly acknowledges UEFISCDI for financial support (project PN-III-P4-ID-PCE-2016-0146, Nr. 121/2017).

The catalytic, extremely effective enantioselective conjugate-addition strategy was approved by via 4 mol% of bis(oxazoline)-Mg(OTf)2 along with amine complex as co-catalyst. The magnicium triflate based catalysis afford 88% selectivity in the molecule and provide less dependence on the tartrate salt for enantioselectivity, which was previously prepared for attaining chiral purity for the synthesis of the endothelin-A antagonist ABT-546. Along with enantioselective conjugate-addition the new strategy involves green solvents in the final steps of ABT-546 drug preparation. The use of green solvent owes its own advantage of minimizing the residues remaining in the API synthesized. The article includes the case study of the ABT-546 to discuss the green chemistry objectives fulfilled by pharma industry.

The installation of (benzo)thiophene-containing biaryls via coupling reactions has become a staple in designing photoelectric materials. Undeniably, C-H/C-H cross-coupling reactions between two (hetero)aromatics would be a shortcut toward these structural fragments. While more reliable cross-coupling technologies are well-established to provide C2-arylated (benzo)thiophenes, efficient methods that arylate the C3-position remain underdeveloped. Herein we provide insight into the factors that determine regioselectivity switching for these cross-coupling reactions. X-ray crystallographic analysis gives solid evidence for the key roles of triflate in regioselective dearomatization and acetate in base-assisted anti-β-deprotonated rearomatization. The first isolation and X-ray characterization of a medium-sized dearomatized cyclometalated adduct involving both substrates provide extra insight into aerobic oxidative Ar-H/Ar-H cross-coupling reactions. The mechanistic breakthrough incubates the first example, enabling C-H/C-H-type C3-arylation of benzothiophenes. Finally, this chemistry is used to design blue-emitting thermally activated delayed fluorescence (TADF) materials with a helicene conformation that exhibit a high maximum external quantum efficiency of 25.4% in OLED.

While aqueous Zn-Na hybrid batteries have garnered widespread attention because of their low cost and high safety, it is still challenging to achieve long cycle-life and stable discharge-voltage due to sluggish reaction kinetics, zinc dendrite formation, and side reactions. Herein, we design a Zn2+/Na+ dual-salt battery, in which sodiation of the NVP cathode favors zinc intercalation under an energy threshold, leading to decoupled redox reactions on the cathode and anode. Systematic investigations of the electrolyte effects show that the ion intercalation mechanism and the kinetics in the mixture of triflate- and acetate-based electrolytes are superior to those in the common acetate-only electrolytes. As a result, we have achieved fast discharging capability, suppressed zinc dendrites, a stable discharge voltage at 1.45 V with small polarization, and nearly 100% Columbic efficiency in the dual-salt mixture electrolyte with optimized concentration of 1 M Zn(OAc)2 + 1 M NaCF3SO3. This work demonstrates the importance of electrolyte regulation in aqueous dual-salt hybrid batteries for the energy storage.

Herein, we report the stabilization of nitrene reagents as the source of a nitrogen atom to synthesize nitrogen-incorporated R1 LSi-N←SiLR2 (1) [L=PhC(NtBu)2 ; R1 =NTMS2 , R2 =NTMS]. Compound 1 is synthesized by reacting LSi(I)-SiI L with 3.1 equivalents of Me3 SiN3 at low temperature to afford a triene-like structural framework. Whereas the reaction of the LSi(I)-SiI L with 2.1 equivalents of Me3 SiN3 at room temperature produced silaimine 2 with a central four-membered Si2 N2 ring which is accompanied by a silylene LSi and a cleaved silylene fragment. 1 further reacts with AgOTf at room temperature to yield compound 3 which shows coordination of nitrene to silver with the triflate salt. The compounds 1 and 2 were fully characterized by NMR, mass spectrometry, and X-ray crystallographic analysis. The quantum mechanical calculations reveal that compounds 1 and 2 have dicoordinated monovalent N atoms having two active lone pairs of electrons. These lone pairs are stabilized by hyperconjugative interactions.

The synthesis of 2-oxygenated dihydrobenzofurans involving the [3 + 2] coupling of quinone monoacetals with vinyl ethers has been realized by tetrabutylammonium triflate catalysis. The reaction involves a new activation method of the acetal moiety in quinone monoacetals under acid-free conditions affording the highly oxygenated dihydrobenzofurans. This new activation mode was achieved by using the triflate anion catalyst for stabilization of the highly reactive cationic intermediate.

A cyclometalated NHC-coordinated hydrido tantalum alkoxide was found to selectively react with CO2 to afford the genuine tantalum formate (NHC)(HCOO)Ta(ORF)3 with ORF = OC(CF3)2CH3. In the solid state, the presence of a κ2-O,O-formate moiety was established by single-crystal X-ray diffraction and ATR-IR spectroscopy, while NMR experiments and DFT modeling studies suggest that the κ1-O-coordination mode is preferred in solution. Despite the accessibility of the latter κ1-O-formate in solution, no over-reduction to a dinuclear methylene diolate was observed. Upon treatment with MeOTf, the κ1-O-formate was methylated selectively, which led to the formation of a tantalum triflate complex along with methyl formate. This is a rare example in which a value-added oxygen-containing organic product (here HCOOMe) is released from an oxophilic early transition metal (here TaV).

A variety of 4-trifluoromethylquinolines bearing an aryl (or cyclopropyl, tert-butyl, trimethylsilyl) group at C-2 and a nitro group at ring position 6, 7 or 8 have been prepared in good to high yields from 3-substituted 1-(trifluoromethyl)prop-2-yne 1-iminium triflate salts and o-, m- or p-nitroaniline. These reactions include an aza-Michael reaction at room temperature followed by an intramolecular electrophilic aromatic substitution step, which requires additional thermal activation in most cases. In contrast, the conjugate addition of 2,4-dinitroanilines at the acetylenic iminium ions proceeds much more slowly and some of the adducts can be converted thermally into 2-(2,4-dinitrophenyl)-5-trifluoromethylpyrroles. Analogously, 2-(4-pyridyl)-5-trifluoromethylpyrroles were obtained from 3-aryl-1-(trifluoromethyl)propyn­iminium salts and 4-aminopyridinium triflate. A novel variation of the Truce–Smiles rearrangement is probably involved in the formation of these pyrroles.

The development of low-cost and eco-friendly aqueous electrolytes with a wide voltage window is the key to achieving safe high energy density supercapacitors (SCs). In this work, a molecular crowding electrolyte is prepared by simulating the crowded environment in living cells. Ion transport in the molecular crowding electrolyte can be effectively improved via reducing the molecular weight of the crowding agent, polyethylene glycol (PEG). The results show that PEG with a molecular weight of 200 (PEG200) can significantly improve ionic conductivity while maintaining a wide voltage window. These advantages enable commercial activated carbon-based SCs to work at 2.5 V with high energy density, outstanding rate performance and good stability for more than 10, 000 cycles. On this basis, three series of molecular crowding electrolytes using sodium perchlorate, lithium perchlorate, and sodium trifluoromethanesulfonate as salts are developed, demonstrating the versatility of PEG200 for wide-voltage aqueous electrolytes.

1,3-Bis(trifluoromethyl)prop-2-ene 1-iminium triflate salts were prepared for the first time and some synthetic applications as 1,3-biselectrophilic building blocks were established. They were found to react with dimethoxybenzenes or methylene-1,2-dioxybenzenes to furnish vinylogous trifluoroacetylation products (4-aryl-1,1,1,5,5,5-hexafluoropent-3-en-2-ones) and 1-dialkylamino-1,3-bis(trifluoromethyl)-1H-indenes. With aniline and ring-substituted anilines, 2,4-bis(trifluoromethyl)quinolines were formed. An unusual 4H-pyran, formally a condensation product of the N,N-dimethyl-1,3-bis(trifluoromethyl)prop-2-en-1-iminium ion and its enaminone precursor, is also reported.

High-valent iron halide corroles were examined to determine their reactivity with carbon radicals and their ability to undergo radical rebound-like processes. Beginning with Fe(Cl)(ttppc) (1) (ttppc = 5,10,15-tris(2,4,6-triphenylphenyl)corrolato(3−)), the new iron corroles Fe(OTf)(ttppc) (2), Fe(OTf)(ttppc)(AgOTf) (3), and Fe(F)(ttppc) (4) were synthesized. Complexes 3 and 4 are the first iron triflate and iron fluoride corroles to be structurally characterized by single crystal X-ray diffraction. The structure of 3 reveals an Ag(I)─pyrrole (η(1) − π) interaction. The Fe(Cl)(ttppc) and Fe(F)(ttppc) complexes undergo halogen transfer to triarylmethyl radicals, and kinetic analysis of the reaction between (p-OMe-C(6)H(4))(3)C• and 1 gave k = 1345 ± 34 M(−1) s(−1) at 23 °C and 2.18 ± 0.17 M(−1) s(−1) at −60 °C, and ΔH(⧧) = +9.77 ± 0.29 kcal mol(−1); ΔS(⧧) = −14.39 ± 1.29 cal mol(−1) K(−1) through an Eyring analysis. Complex 4 is significantly more reactive, giving k = 1.158 x 10(5) ± 0.064 M(−1) s(−1) at 23 °C. The data point to a concerted mechanism, and show the trend X = F(−) > Cl(−) > OH(−) for Fe(X)(ttppc). This study provides mechanistic insights into halogen rebound for an iron porphyrinoid complex.

A new series of nanocomposite polymer electrolytes (NCPEs) was prepared using poly(vinylidene fluoride–co–hexafluoro propylene) P(VdF-HFP) as polymer, magnesium triflate (MgTr) as salt and nano-sized barium titanate (BaTiO3) (3 was revealed through X-ray diffraction (XRD) analysis. From AC impedance spectroscopy, maximum conductivity of 4.11 × 10−4 Scm−1 was attained for the addition of 6 wt% of nano BaTiO3 to the P(VdF-HFP)/MgTr matrix. Dielectric studies were found to be in accordance with the ionic conductivity studies. For the most highly conducting sample, a greater number of mountain valley pattern was observed from Atomic Force Microscopy (AFM) analysis. Thermal stability of the sample, P(VdF-HFP)/MgTr/BaTiO3 (6 wt%) (which possessed maximum ionic conductivity) was observed through TG/differential thermal analysis studies. All these results suggested that these materials are favorable and find application in practical electrochemical devices.

International audience; Catalytic transformation of oxygenated compounds is challenging in f-element chemistry due to the high oxophilicity of the f-block metals. We report here the first Meerwein–Ponndorf–Verley (MPV) reduction of carbonyl substrates with uranium-based catalysts, in particular from a series of uranyl(VI) compounds where [UO2(OTf)2] (1) displays the greatest efficiency (OTf = trifluoromethanesulfonate). [UO2(OTf)2] reduces a series of aromatic and aliphatic aldehydes and ketones into their corresponding alcohols with moderate to excellent yields, using iPrOH as a solvent and a reductant. The reaction proceeds under mild conditions (80 °C) with an optimized catalytic charge of 2.3 mol % and KOiPr as a cocatalyst. The reduction of aldehydes (1–10 h) is faster than that of ketones (>15 h). NMR investigations clearly evidence the formation of hemiacetal intermediates with aldehydes, while they are not formed with ketones.

The knowledge of water solubility in ionic liquids (ILs) is an important property with an impact on the design of many physical and chemical processes, like the purification of organic compounds or the establishment of decontamination procedures. The development of methods to predict or establish solubility trends in ILs is, therefore, extremely relevant, as it may avoid expensive and time-consuming experimental procedures. In this work, we compare results of water solubility in ILs predicted by a quantitative structure-property relationship (QSPR) model with trends found using aggregation studies in molecular dynamics (MD) simulation results. This study was performed for ILs combining the cations 1-butyl-1-methylpyrrolidinium and 1-butyl-1-methylmorpholinium, with the anions bis(pentafluoroethylsulfonyl)imide (BETI-), trifluoromethanesulfonate (TF-), and tetrafluoroborate (BF4-). Both methods indicated that, at 298.15 K, the water solubility in ILs was almost independent of the investigated cations. However, if the IL is composed of a hydrophobic anion, a slight increase in the mixability of the IL with water may be observed if the cation can form H-bonds. The QSPR model indicated that the hydrophobic BETI- anion leads to solubilities (xH2O ∼ 0.33), approximately half of those predicted when the cations are combined with TF- and BF4- anions (xH2O ∼ 0.60). The MD results suggested that this difference is essentially related to the ability of the water molecules to interact with the anion. This interaction involves the formation of networks of molecules, where H2O is completely solvated by anions. These structures make the formation of interactions between water molecules difficult, which are responsible for their segregation from solution and, therefore, to liquid-liquid phase separation. For the investigated ILs, the MD data also suggest that the solubility trends are inversely proportional to the number of "isolated" anions relative to ···AN-H2O-AN-H2O··· networks.

In this paper, performance enhancement of magnesium ion conducting solid polymer electrolyte has been investigated with the incorporation of urea in it. The standard solution casting technique has been adopted to fabricate solid polymer electrolyte consisting of poly(ethylene oxide) (PEO) polymer, magnesium triflate (MgTf2) salt and urea. Measurement on conductivity, dielectric and modulus is carried out on the electrolyte films as a function of frequency at various temperatures. On the introduction of urea in PEO/MgTf2 matrix, the ionic conductivity improves by an order of magnitude and the relaxation time decreases from 0.45 to 0.16 µs. The highest conductivity of 6.3 × 10–5 S cm−1 has been recorded for PEO/MgTf2/Urea polymer electrolyte system. The ionic conductivity versus temperature plots suggests the Arrhenius behavior within the electrolyte compositions. The number density of the free ions increases by an order of magnitude from 1020 to 1021 on the addition of urea in PEO/MgTf2 matrix without any significant change in mobility values. The conductivity, dielectrics, surface morphology and X-ray diffraction studies reveal that urea is not only improving the porous structure but also interacting with the PEO/MgTf2 matrix to improve the ion dynamics. This approach toward improved ion-transport behavior may be utilized in fabricating high-performance electrolytes, especially for magnesium batteries.

In an effort to probe the impacts of speciation on spin-state switching, the synthesis and unique solution-phase magnetic properties of [((TIPSC≡C)3tren)Fe(OTf)2] (1) are described. Analysis of the single-crystal X-ray diffraction data shows that the tris(iminoalkyne) ligand coordinates to the iron(II) center through all four nitrogen atoms, while the other two coordination sites are filled by the oxygen atoms from triflate anions. Solid-state variable-temperature (VT) magnetic studies show that 1 remains high-spin (HS) at all temperatures. In the presence of moderately strong coordinating solvents, solvent replaces the two bound triflate counteranions, as observed by 19F NMR spectroscopy and supported by conductivity measurements. VT solution measurements show 1 to be in the HS state when this solvent is oxygen-donating but low-spin (LS) with a nitrogen-donating solvent. In the noncoordinating solvent dichloromethane, both triflates are bound to the iron(II) center at room temperature, but upon cooling, 1 undergoes a coordination change, resulting in the loss of one triflate, as shown by 19F NMR. With the moderately coordinating solvent acetone, triflate dissociation upon cooling results in a spin-switching species with a T1/2 value of 171 K, characterized via 19F NMR, Evans' method, and solution magnetometry measurements. Solution magnetic measurements collected in structurally similar cyclopentanone suggest that the spin-state switching event is exclusive to the acetone environment, suggesting the influence of both the local coordination environment and aggregation. Additionally, a comparison of the solvodoynamic diameters via dynamic light scattering suggests that aggregation of 1 is significantly different in (CH3)2CO and (CD3)2CO, leading to the observation of spin-switching behavior in the former and fully HS behavior in the latter. This study highlights the sensitivity of solution magnetic properties to solvent choice.

Tandem catalytic reactions improve atom- and step-economy over traditional synthesis but are limited by the incompatibility of the required catalysts. Herein, we report the design of bifunctional metal-organic layers (MOLs), HfOTf-Fe and HfOTf-Mn, consisting of triflate (OTf)-capped Hf6 secondary building units (SBUs) as strong Lewis acidic centers and metalated TPY ligands as metal active sites for tandem catalytic transformations using O2 and CO2 as coreactants. HfOTf-Fe effectively transforms hydrocarbons into cyanohydrins via tandem oxidation with O2 and silylcyanation whereas HfOTf-Mn converts styrenes into styrene carbonates via tandem epoxidation and CO2 insertion. Density functional theory calculations revealed the involvement of a high-spin FeIV (S = 2) center in the challenging oxidation of the sp3 C-H bond. This work highlights the potential of MOLs as a tunable platform to incorporate multiple catalysts for tandem transformations.

The trifluoromethyl group is a prominent motif in biologically active compounds and therefore of great interest for the labeling with the positron emitter fluorine-18 for positron emission tomography (PET) imaging. Multiple labeling strategies have been explored in the past; however, most of them suffer from low molar activity due to precursor degradation. In this study, the potential of 1-(difluoromethyl)-3-methyl-4-phenyl-1H-1,2,3-triazol-3-ium triflate as precursor for the synthesis of the [18 F]trifluoromethylation building block [18 F]fluoroform with high molar activity was investigated. The triazolium precursor was reacted under various conditions with [18 F]fluoride, providing [18 F]fluoroform with radiochemical yields (RCY) and molar activities (Am ) comparable and even superior with already existing methods. Highest molar activities (Am = 153 ± 14 GBq/μmol, dc, EOS) were observed for the automated procedure on the Neptis® perform module. Due to its easy handling and good RCY and Am in the [18 F]fluoroform synthesis, the triazolium precursor is a valuable alternative to already known precursors.

N,N-Diacetylimido protection of 2-aminoglycosides is an elegant strategy but has had limited applications due to unexpected side reactions in glycosylation. We found that high acid concentrations could diminish the side reactions. We observed intermolecular hydrogen bonding among alcohols and acids could disrupt. Assuming that intermolecular hydrogen bonding accelerates the formation of 1,2-orthoamides and disrupting intermolecular hydrogen bonds could turn to the desired glycosylation, we successfully employed sulfenyl triflate pre-activation in the glycosylation of a broad scope of alcohol acceptors, as well as in a one-pot synthesis of a protected human milk oligosaccharide, lacto-N-neotetraose.

The synthesis, structure, and spectroscopic characterization of a pincer-type compound; N,N′-di(pyridine-4-yl)-pyridine-3,5-dicarboxamide is described. The tricationic pro-ligand (C20H22N5O2)3+ bearing two pendant alkylated 4-pyridyl arms at the 3,5-positions of the central pyridyl group features three triflate anions (CF3SO3−) in the asymmetric unit. Two of the triflate ligands in the structure are connected to the pincer cation by strong N–H⋯O hydrogen bonds. The central N-methyl moiety is planar to a r.m.s deviation of 0.01, and the two adjacent N-methylpyridine moieties are out of the plane with dihedral angles of 33.62° (3) and 86.08° (3). The molecular packing structure of the compound shows an 18-molecule aggregate in a 3-dimensional supramolecular synthon stabilized by intermolecular N–H⋯O and C–H⋯O contacts. The Hirshfeld surface analysis and fingerprint plots show that the OH/HO contacts resulting from C–H⋯O intermolecular interactions contributed significantly to the overall surface interaction with a total percentage contribution of 35.4%. The pairwise interaction energy calculations were implemented with a Gaussian plugin in Crystal Explorer 17 at the B3LYP/6-31G(d,p) level of theory. Energy profile diagrams and interaction energy values indicate that the crystal structure was stabilized by a combination of electrostatic and dispersion forces in the crystal lattice. The crystal structure of a tricationic pro-ligand N,N′-di(pyridine-4-yl)-pyridine-3,5-dicarboxamide is described. The structures features three triflate anions in the asymmetric unit with two of the triflate ligands in the structure connected to the pincer pro-ligand by strong N–H⋯O hydrogen bonds. Hirshfeld surface interaction and pairwise interaction energies are explored.

The temperature glass behavior of epoxy deproteinized natural rubber/polymethylmethacrylate/lithium trifluoromethanesulfonate (EDPNR/PMMA/LiCF3SO3) and the conductivity behavior of EDPNR in the ternary blends were studied by DSC and multichannel potentiostat. The DSC result revealed the temperature glass of the EDPNR was shifted to the right with the increase of lithium salt amount in these binary blends composition. However, in the ternary blends of EDPNR/PMMA/LiCF3SO3 the temperature glass revealed the miscibility of these ternary blends. Two different temperature glass values were obtained when the ratio of EDPNR in EDPNR/PMMA was less than 80 wt.%. The ionic conductivity of EDPNR could be improved by increasing the amount of lithium salt up to 35 wt.%, after this amount the ionic conductivity of EDPNR was significantly decreased. While in the ternary blends, the highest ionic conductivity value was found at the ratio 80/20 of EDPNR/PMMA. Furthermore, the factors influencing the temperature glass and conductivity behavior of EDPNR were systematically studied in this work. The results demonstrated an intimate correlation between temperature glass and conductivity behavior of EDPNR.

Tandem [4+2]/[4+2] cycloaddition between bis-dienes containing two furan rings and dehydrobenzene as a dienophile was studied. It was shown that dehydrobenzene generated in situ from 2-(trimethylsilyl)phenyl trifluoromethanesulfonate is capable of a facile intermolecular [4+2] cycloaddition to a furan moiety of a diene at room temperature. The next step, that involves intramolecular Diels–Alder reaction (the IMDAF reaction) with the second furan ring, requires elevated temperature up to 80°С. It has been shown that even under optimal conditions the yields of the target annulated 1,4:5,8-diepoxynaphthalenes do not exceed 50%. The main byproducts are double cycloaddition adducts formed during the interaction of two aryne subunits with both furan rings of the initial bis-diene.

Gel polymer electrolyte based on poly (vinyl alcohol)(PVA)–magnesium triflate (MgTf) incorporating with different weight percentage (wt.%) of ethylene carbonate (EC) as plasticizer has been prepared by using solution casting method. The ionic conductivity of PVA–MgTf–EC gel polymer electrolyte has been determined by using Electrochemical Impedance Spectroscopy (EIS) and has achieved an optimum value at 1.26 x 10-4 S.cm-1 when 50 wt.% of EC is added into the system. Fourier Transform Infrared Spectroscopy (FTIR) has been performed to study the molecular interaction between components in PVA-MgTf-EC gel polymer electrolyte. The complexations between the materials used in the electrolyte system are observed based on the shifting of bands and changes in the intensity of peaks in FTIR spectra. The morphological behaviour of electrolytes has been studied by using Field Emission Scanning Electron Spectroscopy (FESEM) to observe the changes of PVA-based gel polymer electrolytes when EC is added to the system. The amorphous peak of PVA-based electrolyte is observed to become broaden with the addition of plasticizer, results in increment in the amorphousness nature of the electrolyte which is determined by X-ray Diffractometer (XRD).

We have studied the adsorption, wetting, growth, and thermal evolution of the protic IL diethylmethylammonium trifluoromethanesulfonate ([dema][TfO]) on Au(111) and Ag(111). Ultrathin films were deposited at room temperature (RT) and at 90 K, and were characterized in situ by angle-resolved X-ray photoelectron spectroscopy. For both surfaces, we observe that independent of temperature, initially, a closed 2D wetting layer forms. While the film thickness does not increase past this wetting layer at RT, at 200 K and below, "moderate" 3D island growth occurs on top of the wetting layer. Upon heating, on Au(111), the [dema][TfO] multilayers desorb at 292 K, leaving an intact [dema][TfO] wetting layer, which desorbs intact at 348 K. The behavior on Ag(111) is much more complex. Upon heating [dema][TfO] deposited at 90 K, the [dema]+ cations deprotonate in two steps at 185 and 305 K, yielding H[TfO] and volatile [dema]0. At 355 K, the formed H[TfO] wetting layer partly desorbs (∼50%) and partly decomposes to form an F-containing surface species, which is stable up to 570 K.

A series of zinc complexes of 2,7-bis(2-pyridyl)-1,8-naphthyridine (BPNP) has been synthesised and characterised by single crystal X-ray diffraction and solution state NMR spectroscopic studies. Reactions of BPNP with zinc acetate and zinc chloride were found to give mononuclear complexes of the form [Zn(BPNP)X2] (X = OAc, Cl), whereas reactions with zinc triflate led to a mixture of products. Several of these were identified crystallographically as [Zn(BPNP-H)(H2O)4](OTf)3 and [Zn(BPNP-H)(NCMe)(OTf)2]OTf, in which protonation of one pyridyl group occurred, and the dimeric species [Zn2(BPNP)4(μ-H2O)2](OTf)4. A trimetallic complex [Zn3(μ2-BPNP)(μ2-OAc)3(OAc)2(μ3-OH)] was also isolated from reactions involving zinc acetate, and demonstrates the ability of BPNP to coordinate two zinc atoms in the adjacent binding pockets.

Herein, we report a hydrodefluorination reaction of polyfluoroarenes catalyzed by bismuthinidenes, Phebox-Bi(I) and OMe-Phebox-Bi(I). Mechanistic studies on the elementary steps support a Bi(I)/Bi(III) redox cycle that comprises C(sp2)–F oxidative addition, F/H ligand metathesis, and C(sp2)–H reductive elimination. Isolation and characterization of a cationic Phebox-Bi(III)(4-tetrafluoropyridyl) triflate manifests the feasible oxidative addition of Phebox-Bi(I) into the C(sp2)–F bond. Spectroscopic evidence was provided for the formation of a transient Phebox-Bi(III)(4-tetrafluoropyridyl) hydride during catalysis, which decomposes at low temperature to afford the corresponding C(sp2)–H bond while regenerating the propagating Phebox-Bi(I). This protocol represents a distinct catalytic example where a main-group center performs three elementary organometallic steps in a low-valent redox manifold.

Directly accessible 8-substituted tetrahydroquinolines undergo 1,5-hydride-shift-triggered cyclization to provide difficult to access julolidine derivatives in yields of 21–98% under scandium(III) triflate catalysis. Additionally, the scope of the reaction, several follow-up transformations and a remarkable side process discovered during optimization of the conditions are highlighted.

The synthesis of 2,9‐diaza‐1,3,8,10‐tetratriflato‐dibenzoperylene (DDP 3 a) and corresponding 2,9‐dimethyl‐1,3,8,10‐tetratriflato‐dibenzoperylene (DBP 3 b) has been developed at multigram scale via reduction of one of the industrially most important high‐performance dyes, perylene‐3,4,9,10‐tetracarboxylic diimide (PTCDI), and of the corresponding dihydroxy peropyrenequinone precursor. The focus of this paper is on the reactivity pattern of 3 a as key intermediate towards highly functionalized 2,9‐diazadibenzopyrelenes (DDPs) obtained via catalytic substitution of four triflate by aryl, heteroaryl, alkynyl, aminyl, and O‐phosphanyl substituents. The influence of electron‐donating substituents (OSiMe3, OPt‐Bu2, N‐piperidinyl), electron‐withdrawing (OTf, 3,5‐bis‐trifluoromethyl‐phenyl), and of electron‐rich π‐conjugated (2‐thienyl, 4‐tert‐butylphenyl, trimethylsilyl‐ethynyl) substituents on optoelectronic and structural properties of these functionalized DDPs has been investigated via XRD analyses, UV/Vis, PL spectroscopy, and by electroanalytical CV. These results were correlated to results of DFT and TD‐DFT calculations. Thus, functionalized DPPs with easily tunable HOMO and LUMO energies and gap became available via a new and reliable synthetic strategy starting from readily available PTCDI., A versatile approach towards 2,9‐diazadibenzoperylenes (DDPs) and related 2,9‐dimethyldibenzoperylenes (DBPs) with various C, O, and N substituents in 1,3,8,10‐positions is presented. It comprises reductive aromatization of PTCDI via O‐silylation and O‐trifylation steps. DDP‐tetratriflate is the strategic key to (hetero)aryl, alkynyl, aminyl or O‐phosphanyl DDPs characterized by UV/Vis/PL spectra, XRD and CV methods and (TD‐)DFT calculations.

Molecular cages with arylboronate ester caps at the vertices are described. The cages were obtained by metal-templated polycondensation reactions of a tris(2-formylpyridine oxime) ligand with arylboronic acids. Suited templates are triflate or triflimide salts of ZnII, FeII, CoII, or MnII. In the products, the metal ions are coordinated internally to the pyridyl and oximato N atoms adjacent to the boronate ester, resulting in an improved hydrolytic stability of the latter. It is possible to decorate the cages with cyano or aldehyde groups using functionalized arylboronic acids. The aldehyde groups allow for a postsynthetic modification of the cages via an imine bond formation.

A simple and environmentally friendly method to prepare S-heterocycles by cyclization of aromatic thiols and diols with H2O as a byproduct is described. The Sc(OTf)3-catalyzed dehydrative cyclizations of aromatic thiols and diols provided the corresponding thiopyran and thiophene derivatives. Control experiments were also performed to obtain insights into the reaction pathway

The increasing interest in developing safe and sustainable energy storage systems has led to the rapid rise in attention to superconcentrated electrolytes, commonly called water-in-salt (WiS). Several works indicate that the transport properties of these liquid electrolytes are related to the presence of nanodomains, but a detailed characterization of such structure is missing. Here, the structural nano-heterogeneity of lithium WiS electrolytes, comprising lithium trifluoromethanesulfonate (LiTf) and bis(trifluoromethanesulfonyl)imide (LiTFSI) solutions as a function of concentration and temperature, was assessed by resorting to the analysis of small-angle neutron scattering (SANS) patterns. Variations with the concentration of a correlation peak, rather temperature-independent, in a Q range around 3.5-5 nm-1 indicate that these electrolytes are composed of nanometric water-rich channels percolating a 3D dispersing anion-rich network, with differences between Tf and TFSI anions related to their distinct volumes and interactions. Furthermore, a common trend was found for both systems' morphology above a salt volume fraction of ∼0.5. These results imply that the determining factor in the formation of the nanostructure is the salt volume fraction (related to the anion size), rather than its molality. These findings may represent a paradigm shift for designing WiS electrolytes.

Herein we report binary acid Sc(OTf)3/TfOH-catalyzed alkenylation of arenes with alkynes. In this system, the high-energy vinyl carbocations with activated and weakly coordinating trifluoromethanesulfonate anions by Lewis acid Sc(III) can undergo facile Friedel-Crafts reactions with arenes to give the desired adducts in up to 90% yield and with high Z-selectivity.

Here we present the design of a new amphiphilic n-(4,4′-trimethyldipyridyl)-(1-dodecyl-1,4,7-triazacyclononane) copper (II) triflate, assigned as Multiplex 1, that self-organizes in water to form three-dimensional nanoscale toroidal structures with an intrinsic affinity to bind and condense DNA strands. Pressed micelles exhibited a standard particle size of about 26 nm, reported by dynamic light scattering. Using flow cytometry, it was showed that these micelles could transfect a reporter gene pEGFPN1 to HEK 293-T cells. Also, a non-hydrophobic structural equivalent, called 4,4′-trimethyldipyridyl-(1,4,7-triazacyclononane) copper (II) triflate (Multiplex 2) was synthesized and characterized by X-ray crystallography to report the chemical environment all over the copper (II) ion in Multiplex 1. We demonstrate that metal-ion coordination and lipid alkane interdigitation mediate the molecules´ self-assembly and that intracellular conditions reverse this type of supramolecular organization. This work proposes that transition metal-mediated compounds that self-assembly can form cheap complex nanoparticles possessing gene transfection properties.

Summary Covalent organic frameworks (COFs) have emerged as a new class of molecularly precise, porous functional materials characterized by broad structural and chemical versatility, with a diverse range of applications. Despite their increasing popularity, fundamental aspects of COF formation are poorly understood, lacking profound experimental insights into their assembly. Here, we use a combination of in situ X-ray powder diffraction and Raman spectroscopy to elucidate the reaction mechanism of mechanochemical synthesis of imine COFs, leading to the observation of key reaction intermediates that offer direct experimental evidence of framework templating through liquid additives. Moreover, the solid-state catalyst scandium triflate is instrumental in directing the reaction kinetics and mechanism, yielding COFs with crystallinity and porosity on par with solvothermal products. This work provides the first experimental evidence of solvent-based COF templating and is a significant advancement in mechanistic understanding of mechanochemistry as a green route for COF synthesis.