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The synthesis of the complex containing manganese(II), bipyridine (bipy) as a ligand, and an anionic trifluoromethane sulfonate (triflate) is reported. The corresponding metal content, conductance, and DTG-TGA of the complex lead to the formula of [Mn(bipy)3](triflate)2·5.5H2O. The fully high-spin magnetic moment is observed, corresponding to five unpaired electrons in the metal ion. The electronic spectral bands suggest the three possible spin-forbidden transitions of the sextet to quartet states. The mode of vibrations of the IR spectrum supports the typical ring of bipy, and the triflate. The images of SEM-EDX indicate the presence of the corresponding elemental content and reflect the relatively high crystallinity, as it is evidenced in the profile of the corresponding powdered diffractogram. The refinement of powdered XRD following the Le Bail program suggests being structurally triclinic symmetry of P21/c. This complex shows inhibition of bacterial activity against S. aureus and E. coli.

We report the discovery of a straightforward protocol to convert phenols into the corresponding aryl triflates using 1‐methyl‐3‐((trifluoromethyl)sulfonyl)‐1,3‐dihydro‐2H‐benzo[d]imidazol‐2‐one in the presence of a fluoride source. This novel reagent can be handled without any precautions to exclude air or moisture making this method highly convenient. The reactions generally show very clean conversions within only a few minutes at room temperature. The mild conditions allow the so far unprecedented O‐triflation of tyrosine in peptides bearing challenging side chains present for example in arginine and histidine including the late‐stage triflation of complex bioactive peptides. We show how aryl triflates – an interesting but so far underutilized group – can be used to optimize physicochemical and in vitro properties of compound series in medicinal chemistry. We believe that this method is highly attractive for applications in peptide functionalization as well as automated and medicinal chemistry. [ABSTRACT FROM AUTHOR]

The autoreduction of ammonium pertechnetate in solutions of trifluoromethanesulfonic acid (triflic acid, TfOH) and trifluoromethanesulfonic anhydride (triflic anhydride, TfOTf) results, in the presence of sodium ions, in the formation of the complex Na2[(TcVO)(OTf)5] · 2(TfOH). Its structure has been determined by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

Treatment of N‐methyl‐S,S‐diaryl sulfoximines with methyl trifluoromethanesulfonate provides bench‐stable sulfoxinium salts in excellent yields. Applying them in Sonogashira‐, Heck‐ and Suzuki‐type cross‐coupling reactions leads to the corresponding products by sequential C−S bond cleavage and C−C bond formation. Electronic factors induced by substituents on the S‐aryl groups govern the coupling efficiency. [ABSTRACT FROM AUTHOR]

This study investigates the nucleation and growth of micro-/nanodroplets of triflate-based ionic liquids (ILs) fabricated by vapor deposition on different surfaces: indium tin oxide (ITO); silver (Ag); gold (Au). The ILs studied are constituted by the alkylimidazolium cation and the triflate anion—[CnC1im][OTF] series. One of the key issues that determine the potential applications of ILs is the wettability of surfaces. Herein, the wetting behavior was evaluated by changing the cation alkyl chain length (C2 to C10). A reproducible control of the deposition rate was conducted employing Knudsen cells, and the thin-film morphology was evaluated by high-resolution scanning electron microscopy (SEM). The study reported here for the [CnC1im][OTF] series agrees with recent data for the [CnC1im][NTf2] congeners, highlighting the higher wettability of the solid substrates to long-chain alkylimidazolium cations. Compared to [NTf2], the [OTF] series evidenced an even more pronounced wetting ability on Au and coalescence processes of droplets highly intense on ITO. Higher homogeneity and film cohesion were found for cationic groups associated with larger alkyl side chains. An island growth was observed on both Ag and ITO substrates independently of the cation alkyl chain length. The Ag surface promoted the formation of smaller-size droplets. A quantitative analysis of the number of microdroplets formed on Ag and ITO revealed a trend shift around [C6C1im][OTF], emphasizing the effect of the nanostructuration intensification due to the formation of nonpolar continuous domains. [ABSTRACT FROM AUTHOR]

The constitutional challenge of an electrostatically directed meta borylation of sterically biased and unbiased substrates is summarized in the present work. The borylation follows an electrostatic interaction between the partially positive and negative charges of the ligand and substrate, respectively. Using our developed strategy, it has been demonstrated that a wide range of challenging substrates, especially 4-substituted substrates can be borylated at the meta position with excellent selectivity. Moreover, unsubstituted substrates are also displayed excellent meta selectivity. The reaction employs bench-stable ligand, proceeds at moderate reaction temperature (40–80 °C), precluding the need to synthesize bulky and sophisticated ligand/template. [ABSTRACT FROM AUTHOR]

Teraryl‐based α‐helix mimetics have proven to be useful compounds for the inhibition of protein‐protein interactions (PPI). We have developed a modular and flexible approach for the synthesis of teraryl‐based α‐helix mimetics using a benzene core unit featuring two leaving groups of differentiated reactivity in the Pd‐catalyzed cross‐coupling used for teraryl assembly. In previous publications we have introduced the methodology of 4‐iodophenyltriflates decorated with the side chains of some of the proteinogenic amino acids. We herein report the core fragments corresponding to the previously missing amino acids Arg, Asn, Asp, Met, Trp and Tyr. Therefore, our set now encompasses all relevant amino acid analogues with the exception of His. In order to be compatible with the triflate moiety, some of the nucleophilic side chains had to be provided in a protected form to serve as stable building blocks. Additionally, cross‐coupling procedures for the assembly of teraryls were investigated. [ABSTRACT FROM AUTHOR]

This study investigates the nucleation and growth of micro-/nanodroplets of triflate-based ionic liquids (ILs) fabricated by vapor deposition on different surfaces: indium tin oxide (ITO); silver (Ag); gold (Au). The ILs studied are constituted by the alkylimidazolium cation and the triflate anion—[CnC1im][OTF] series. One of the key issues that determine the potential applications of ILs is the wettability of surfaces. Herein, the wetting behavior was evaluated by changing the cation alkyl chain length (C2 to C10). A reproducible control of the deposition rate was conducted employing Knudsen cells, and the thin-film morphology was evaluated by high-resolution scanning electron microscopy (SEM). The study reported here for the [CnC1im][OTF] series agrees with recent data for the [CnC1im][NTf2] congeners, highlighting the higher wettability of the solid substrates to long-chain alkylimidazolium cations. Compared to [NTf2], the [OTF] series evidenced an even more pronounced wetting ability on Au and coalescence processes of droplets highly intense on ITO. Higher homogeneity and film cohesion were found for cationic groups associated with larger alkyl side chains. An island growth was observed on both Ag and ITO substrates independently of the cation alkyl chain length. The Ag surface promoted the formation of smaller-size droplets. A quantitative analysis of the number of microdroplets formed on Ag and ITO revealed a trend shift around [C6C1im][OTF], emphasizing the effect of the nanostructuration intensification due to the formation of nonpolar continuous domains.

Beryllium and BeCl2 were treated with trifluoromethanesulfonic acid and trimethylsilyltriflate, respectively to form beryllium triflates BeL2(OTf)2 (L=H2O, THF, nBu2O). The Be–O atomic distances (1.605–1.635 Å) between Be2+ and the triflate anions in solid state are the shortest known distances of this kind in a metal triflate yet. Attempts to remove the solvate molecules led to the decomposition of the obtained compounds. [ABSTRACT FROM AUTHOR]

Herein, the synthesis and characterization of dicationic dichalcogenide compounds [(SIPr)E]2(OTf)2 (3a‐E) (E = S, Se, Te) based on a saturated N‐heterocyclic carbene (NHC), SIPr [SIPr = C{N(Dipp)CH2}2, Dipp = 2,6‐iPr2C6H3] are reported. Treatment of SIPr (1a) with elemental chalcogens affords the heavier ketone derivatives (SIPr)E (2a‐E), which readily undergo oxidative E–E coupling reactions with triflic anhydride to yield the corresponding products 3a‐E. Compounds 3a‐E are air‐stable crystalline solids and were characterized by NMR and UV/Vis spectroscopy as well as by X‐ray diffraction methods. [ABSTRACT FROM AUTHOR]

A new levofloxacin derivative using silver triflate with antibacterial activity was synthesized and characterized. The new compound has been physicochemically characterized through elemental analysis, spectroscopic and thermal methods. All correlated experimental data suggested that the levofloxacin triflate was obtained. The antibacterial activity of the new compound was tested against six Gram-positive and Gram-negative bacteria. In vitro, the new compound had similar activity to levofloxacin against Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae and very closed to the minimum inhibitory concentration values of levofloxacin against Staphylococcus aureus MRSA, Enterococcus faecalis, and Pseudomonas aeruginosa. [ABSTRACT FROM AUTHOR]

The mononuclear title complex, [Fe(CF3O3S)(C5H7O2)2(C4H8O)] or [Fe(acac)2(OTf)(THF)] (acac = acetylacetonate; OTf = trifluoromethanesulfonate; THF = tetrahydrofuran), (I), consists of one six-coordinate Fe3+ atom in a slightly distorted octahedral environment [Fe—O bond-length range = 1.9517 (11)–2.0781 (11) Å]. The triflate ligand was found to be disordered over two sets of sites, with a site-occupancy ratio of 0.622 (16):0.378 (16). Weak intermolecular C—H...O and C—H...F hydrogen-bonding interactions generate a two-dimensional supramolecular structure lying parallel to (100). This is only the second crystal structure reported of a mononuclear bis(acetylacetonato)iron(III) complex.

Iron (III) phthalocyanine complexes were employed for the first time as a mild and efficient Lewis acid catalyst in the selective oxidation of cyclohexene to cyclohexane-1,2-diol. It was found that the catalyst FePcOTf shown excellent conversion and moderate selectivity relative to other iron (III) phthalocyanine complexes. The optimum conditions of the oxidation reaction catalyzed by FePcOTf/H2O2 have been researched in this paper. Iron (III) phthalocyanine triflate (1 mol %) as catalyst, hydrogen peroxide as oxidant, methanol as solvent, and a mole ratio of substrate and oxidant (H2O2) of 1:1 were used for achieving moderate yields of 1,2-diols under reflux conditions after eight hours.

Graphical abstract Highlights • Coordination of bis (pyrazol-3-yl)pyridine pincer ligand to Cr(II) and Cr(III) • CV and DFT calculations conclude that methylated pincer ligand is redox-active. • Nitrate is shown to be a stronger ligand than triflate. • Cr(II) complexes here show Jahn-Teller distortion. Abstract The consequences of installing two versions of a potentially redox active pincer ligand on Cr(III) and Cr(II) are described, and reveal influence of the Jahn-Teller effect. The ligand involves two pyrazole rings attached by pyrazole carbons to the ortho positions of pyridine, thus creating two 1,4-diazabutadiene moieties. In one version, each pyrazole carries an NH proton (H 2 L), while a comparison version (LMe) involves methyl in place of the two weakly acidic protons, to identify the impact of hydrogen bonding. Complexes synthesized include (H 2 L)CrX 3 , where X Cl, triflate and nitrate, (LMe)CrCl 3 and (LMe)Cr(OTf) 3 , together with the divalent metal complexes (H 2 L)CrCl 2 , (LMe)CrCl 2 and (LMe)Cr(OTf) 2. Cyclic voltammetry establishes the relationship between the tri- and divalent triflate complexes of LMe, and DFT calculations indicate further reduction of the latter occurs at the LMe ligand. Nitrate is shown to be a stronger ligand than triflate to Cr(III) here. NaBArF 24 in THF removes only one chloride from (H 2 L)CrCl 2 , to give square pyramidal [(H 2 L)CrCl(THF)]+. [ABSTRACT FROM AUTHOR]

In this study, substituted 1H-pyrazolo[1,2-b]phthalazine-5,10-diones which are considered that may possess biological activity have been obtained via one-pot multi-component cyclocondensation reaction of phthalhydrazide, aromatic aldehydes and malononitrile catalyzed in the presence of Cu(OTf)2 in very good yields and short times. The structures of all these synthesized compounds (4a-f) have been determined and characterized by infrared, nuclear magnetic resonance, mass spectral data, and elemental analysis. [ABSTRACT FROM AUTHOR]

New triptycene derivatives have been synthesised based on the cycloaddition between 1,8‐bis[(trifluoromethanesulfonyl)‐oxy]anthracene as well as 1,8‐bis[(trimethylsilyl)ethynyl]anthracene and p‐benzoquinone. The resulting triptycenequinones were the key compounds for further functionalisation of the triptycene backbone, which were completely characterised by multinuclear NMR spectroscopy, mass spectrometry and X‐ray diffraction experiments. The aim was to substitute the triptycene backbone in positions 1, 8, 13 and 16 to avoid the formation of mixtures of syn‐ and anti‐isomers of trisubstituted triptycenes. Based on the ditriflate‐substituted triptycenequinone triptycene 1,8,13,16‐tetratriflate was synthesised and reacted with alkynyl compounds in cross‐coupling reactions. In further experiments the alkynyl‐substituted triptycene to quinone was directly reacted with lithiated trimethylsilylacetylene or was initially reduced, consequently functionalised with triflate groups and reacted in Sonogashira cross‐coupling reactions. It was found that both reaction pathways generate the anti‐substituted product in position 16 as main product. Triptycenes, with three or four acetylene functions that provide possibilities for further functionalization, are the focus of several preparative approaches starting from di‐functionalised anthracenes and p‐benzoquinone. [ABSTRACT FROM AUTHOR]

Fisetin and 2′,4′,6′-trihydroxydihyrochalcone 4′-O-β-neohesperidoside were synthesized from commercially available quercetin and naringin in five steps. The key steps are site-selective deacetylation and subsequent deoxygenation. The target molecules were obtained in 37% and 23% yields from the starting materials, respectively. [ABSTRACT FROM AUTHOR]

While ionic liquids (ILs) based on a trifluoromethanesulfonate ([OTF] − ) anion and their mixtures with other compounds have been relatively well explored, the information about structurally similar 1,1,2,2-tetrafluoroethanesulfonate-based ([TFES] − ) ILs is either very scarce or, as in the case of their mixtures with water, totally lacking. We herein thus present a broad thermodynamic characterization of aqueous solutions of [EMIM][TFES] and [EMIM][OTF], with the study of aqueous solutions of the latter serving as a benchmark. First, the peculiar solid-liquid phase transition behavior of the neat [EMIM][TFES] was examined and its density was determined over a temperature range encompassing both the subcooled and the stable liquid. For the aqueous solutions of the two ILs, we performed extensive measurements at several temperatures in the range from (288.15 to 318.15) K of water activity ( a w ) across the entire composition range, mixing enthalpy and density specifically in the highly dilute IL region, and the solution freezing temperatures at water mole fractions greater than 0.6. The ample a w data were fitted ( i ) by a two-step procedure and ( ii ) simultaneously with the excess enthalpy data using an extended NRTL-type model. Although both treatments provide adequate representations of the data and prove to yield reasonable estimates of derivative thermal properties, the latter approach to the global description of energetics of the systems is preferred for its handiness in practical calculations. We duly proved its reliability in extrapolation and/or prediction against experimental data on various properties, among others, SLE. The analysis of volumetric data by the Redlich-Meyer equation allowed us to obtain accurate values of infinite dilution partial molar volumes of the ILs and revealed the nature of their hydration as rather hydrophobic. The solution behavior of the systems studied was found to be essentially non-ideal: their small S-shaped excess Gibbs energy ( G E ) actually results from the compensation of their large positive excess enthalpy ( H E ) and entropy ( S E ). Thus, despite being completely miscible with water, the two ILs are not typically hydrophilic, but intermediate on an imaginary (hydrophobicity/hydrophilicity) scale. The structural variation in the anion, though influencing H E and S E considerably, is only subtly reflected in G E and activity coefficients. Due to their somewhat lower values and a weaker decrease of apparent molar volume with increasing molality observed for [EMIM][TFES], [TFES] − is identified to be slightly more hydrophilic than [OTF] − . [ABSTRACT FROM AUTHOR]

The reaction of a series of compounds, Ar3 Ge-MR3, 1–4 (Ar=Ph, p-Tol, M=Si, Ge, R=Ph, Me, tBu), with one equivalent of trifluoromethanesulfonic acid (HOTf) was investigated. The corresponding triflates were isolated in several cases. The molecular structure of Ph3 Ge-GePh2 OTf (5) in solid state was investigated by X-ray analysis. The triflates were converted to the corresponding chlorides under the action of ammonium chloride.

A novel trifunctional initiator with one alkyne and two trifluoromethanesulfonate moieties was synthesized from a protected alcohol 5-hydroxyl-2-phenyl-1, 3-dioxane. The alkyne functionalized intermediate with two protected alcohol groups was synthesized by reacting with propargyl bromide. The alcohol groups were cleaved using a mixture of tetrahydrofuran and hydrochloric acid aqueous solution. In the last step the initiator was synthesized using triflic anhydride in carbon tetrachloride. The initiator was characterized by ¹H NMR and used for the polymerization of 2-ethyl-2-oxazoline which gives polymers with narrow distribution. For comparison a similar initiator with two tosylates was prepared and used for the polymerization of the monomer 2-ethyl-2-oxazoline, the resulting product has a wide molecular weight distribution and most of the initiator remains unreacted after 24 h which may be due to the steric hindrance between the two tosylate groups. To further explore the steric hindrance phenomenon, a linear tosylate initiator was synthesized, but still some of the initiator remains unreacted, illustrating that both steric hindrance and electrophilic balance affect the efficiency of the cationic ring-opening polymerization. All of the polymers were characterized in detail by using ¹H NMR, matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy, and size exclusion chromatography to confirm the purity and distribution of the polymers. [ABSTRACT FROM AUTHOR]

The reaction of [ P,N -{(C 6 H 5 ) 2 (C 5 H 4 N)P}Re(CO) 3 Br] ( RePNBr ) with silver triflate leads to the complex [ P,N -{(C 6 H 5 ) 2 (C 5 H 4 N)P}Re(CO) 3 ( O -CF 3 SO 3 )] ( RePNTfO ) with moderate yield. This new P,N -Re I triflate compound contains the anion directly coordinated to the metal, completing an octahedral environment. RePNTfO displays in dichloromethane (DCM) solution an irreversible oxidation about +1.35 V and three irreversible reduction processes at −1.38 V, −2.03 V and −2.30 V. Oxidation has been attributed to the Re I /Re II couple, while the reduction corresponds to PN -ligand processes, which is consistent with those computed by means of DFT. The absorption spectrum of RePNTfO in DCM displays a maximum at 295 nm ( ε = 7.1 × 10 3 M −1 cm −1 ) and a shoulder around 350 nm ( ε = 1.8 × 10 3 M −1 cm −1 ), which have been assigned to intraligand (π → π ∗ ) and metal to ligand charge transfer (MLCT, dπ → π ∗ ) transitions with the help of DFT/TDDFT. Excitation of RePNTfO in DCM at 350 nm leads to an emission spectrum centered at 535 nm. The analysis of the variation of the absorption and emission spectra in coordinating solvents compared to non-coordinating DCM, DFT/TDDFT calculations modeling and ELF analysis suggests for coordinating solvents that triflate ligand is replaced in the coordination sphere of Re I in solution. Kinetics of the exchange of triflate by bromide measured in DCM at different temperatures allowed to estimate the Eyring parameters: Δ H ≠ , Δ S ≠ and Δ G ≠ , 50.8 kJ mol −1 , −109.6 J K −1 mol −1 and 83.5 kJ mol −1 respectively. The high negative entropy is indicative of a compact transition state, compatible with an associative mechanism, I a , for the exchange. [ABSTRACT FROM AUTHOR]

Pentaphosphaferrocenes [CpRFe(η5-P5)] ( 1) and CuI halides are excellent building blocks for the formation of discrete supramolecules. Herein, we demonstrate the potential of Cu(CF3SO3) for the construction of the novel 2D polymer [{Cp*Fe(μ4,η5:1:1:1-P5)}{Cu(CF3SO3)}]n ( 2) and the unprecedented nanosphere (CH2Cl2)1.4@[{CpBnFe(η5-P5)}12{Cu(CF3SO3)}19.6] ( 3). The supramolecule 3 has a unique scaffold beyond the fullerene topology, with 20 copper atoms statistically distributed over the 30 vertices of an icosidodecahedron. Combinatorics was used to interpret the average disordered structure of the supramolecules. In this case, only two pairs of enantiomers with D5 and D2 symmetry are possible for bidentate bridging coordination of the triflate ligands. DFT calculations showed that differences in the energies of the isomers are negligible. The benzyl ligands enhance the solubility of 3, enabling NMR-spectroscopic and mass-spectrometric investigations. [ABSTRACT FROM AUTHOR]

In the cation of the title salt, C9H20NO+·CF3O3S−, the six-membered heterocyclic ring displays a chair conformation. In the crystal, centrosymmetric pairs of cations and anions are linked by N—H...O and O—H...O hydrogen bonds to form rings with a R44(14) graph-set motif.

A series of solid acid catalysts were prepared by functionalization of graphene-oxide (GO) and MWCNT-oxide (MWCNTO) with triflic and sulfonic acids affording a triflate-functionalized graphene oxide (GO@SO 3 CF 3 ), and a sulfonated MWCNT (μ-CNT-SO 3 H). To facilitate the separation of the catalysts from the reaction mixture MWCNTs were modified by incorporating magnetic nanoparticles. For comparison, the composites of MWCNTO with magnetic nanoparticles were further modified by deposition of niobia in two loadings, e.g. 30 and 60 wt.%. Depending of the functionality the catalysts exposed preponderantly either Brønsted (μ-CNT-SO 3 H) or Lewis (GO@SO 3 CF 3 ) acid sites. Deposition of niobia also led to catalysts with acid properties, but as a function of the precursor nature and loading, they exposed niobia phases with either Brønsted ( e.g. , Nb-O units) or Lewis acid sites ( e.g. , −Nb = O units) in excess. Catalytic performances, in terms of the yields in one of the platform molecule ( ie , levulinic acid versus lactic acid) were directly correlated with the nature of these acid sites. Interestingly enough, the catalysts showing high efficiency for lactic acid led also to high efficiency for the synthesis of succinic acid under pressure of molecular oxygen. [ABSTRACT FROM AUTHOR]

The synthesis, recrystallization, and X‐ray deterimination of N,N,N‐trimethyl‐5‐[(2,3,5,6‐tetrafluorophenoxy)carbonyl]pyridin‐2‐aminium trifluoromethanesulfonate (PyTFP‐precursor), C15H13F4N2O2+·CF3SO3−, is described. This triflate salt precursor is required for the synthesis of 2,3,5,6‐tetrafluorophenyl 6‐[18F]‐fluoronicotinate ([18F]FPyTFP), a prosthetic group used to radiolabel peptides for positron emission tomography (PET), as peptides are increasingly being used as PET‐imaging probes in nuclear medicine. Radiolabeling of peptides is typically done using a `prosthetic group', a small synthon to which the radioisotope is attached in the first step, followed by attachment to the peptide in the second step. During the synthesis of the PyTFP‐precursor, displacement of a Cl atom with trimethylamine gas and anion replacement with a triflate counter‐ion is critical, as incomplete replacement would hinder radioisotopic incorporation of nucleophilic fluorine‐18 and result in diminished radiochemical yields. The structural determination of the PyTFP‐precursor by X‐ray crystallography helped confirm the anion exchange of chloride with triflate. [ABSTRACT FROM AUTHOR]

The crystal structure of the previously known title compound, Ph3SnO3SCF3, was determined by single-crystal X-ray diffraction; it comprises a one-dimensional polymeric structure and pentacoordinated Sn atoms.

In the title compound, C18H13Te2+·CF3O3S−, the TeII atom of the cation and one O atom of the trifluoromethanesulfonate counter-ion form a close-to-linear Te—Te—O system, with a Te—Te—O angle of 172.3 (1)° and a Te—O distance of 2.816 (5) Å, which may suggest the presence of a three-centre–four-electron (3c–4e) bond. Secondary Te...O interactions [3.003 (4) and 3.016 (4) Å], involving the second TeII atom of the binuclear molecule, are also noted, resulting in a supramolecular layer in the bc plane.

The first effective and simple method for the direct one-pot transformation of 2-, 3-, and 4-aminopyridines, 2,6-diaminopyridines, and 2-aminoquinoline into the corresponding pyridinyl and quinolinyl trifluoromethanesulfonates and tosylates in solvents was developed. The procedure involves diazotization of the heterocyclic amines with sodium nitrite in mixed hexane-DMSO or hexane-DMF solutions in the presence of trifluoromethanesulfonic acid or p-toluenesulfonic acid. [ABSTRACT FROM AUTHOR]

Theoretical studies on the lanthanide and actinide triflate complexes M(OTf) where M = La, Ce, Gd, Yb, Lu, Th, U, Np, Pu, Am, Cm, Bk, and No; n = 3 and 4, are carried out using functional density theory (DFT). The study of An(OTf) complexes showed that the three OTf groups are bidentate, generating a trigonal prism (TP). Two limiting structures of TP are observed; the most distorted is the thorium triflate Th(OTf) and the ideal one is U(OTf). The highest population contribution of 5 d orbital compared to 5 f orbital in Th-O bond of Th(OTf) explains the distortion. The intramolecular rearrangement of the OTf ligands in Ln(OTf) generates two conformers. In Yb(OTf), the pseudo-eclipsed and the staggered conformations are stable and can be isolated. [ABSTRACT FROM AUTHOR]

Convenient access to a variety of 2-arylated pyrazolo[1,5-a]pyridine via pyrazolo[1,5-a]pyridine-2-yl triflate using the Suzuki- Miyaura cross-coupling reaction is described. Fifteen 2-arylpyrazolo[ 1,5-a]pyridine derivatives were synthesized in 52-95% yields. [ABSTRACT FROM AUTHOR]

A catalytically active aluminum-based system for Diels-Alder transformations is reported. The system was generated by mixing a β-diketiminate-stabilized aluminum bistriflate compound with Na[BArCl4] (ArCl=3,5-Cl2C6H3). Solid-state analysis of the catalytic system reveals a unique structure incorporating a two-dimensional coordination polymer. According to the experimental results obtained from several Diels-Alder transformations, the aluminum-based system appears to be a more practical and more robust alternative to the recently reported compounds based on carbon and silicon cations. [ABSTRACT FROM AUTHOR]

Iron (III) phthalocyanine complexes were employed for the first time as a mild and efficient Lewis acid catalyst in the selective oxidation of cyclohexene to cyclohexane-1,2-diol. It was found that the catalyst FePcOTf shown excellent conversion and moderate selectivity relative to other iron (III) phthalocyanine complexes. The optimum conditions of the oxidation reaction catalyzed by FePcOTf/H2O2 have been researched in this paper. Iron (III) phthalocyanine triflate (1 mol %) as catalyst, hydrogen peroxide as oxidant, methanol as solvent, and a mole ratio of substrate and oxidant (H2O2) of 1:1 were used for achieving moderate yields of 1,2-diols under reflux conditions after eight hours. [ABSTRACT FROM AUTHOR]

The use of aryl/alkyl sulfenyl triflates as glycosylation promoters is reviewed with a focus on the application of these reagents in glycosylations, in mechanistic studies, and in the syntheses of oligosaccharides. [ABSTRACT FROM AUTHOR]

Abstract: 1-(Phenylthio)-3-(pyridin-3-yl)-2-naphthol was obtained as an unexpected result of a nucleophilic aromatic substitution reaction of 3-(pyridine-3-yl)naphthalene-2-yl trifluoromethanesulfonate with thiophenol. This observation led to the discovery of an easy to handle method to synthesize 1-arylthio-2-naphthols. It has been revealed that electron withdrawing groups on the aryl thiol promoted the yields and heterocycle substituents at the 3-position of the naphthalene core are tolerable by the reaction. This reaction can thus serve as a corner stone in the structural diversification of 3-heterocycle substituted 1-arylthio-2-naphthols as potential inhibitors of cytochrome P450. [Copyright &y& Elsevier]

Recent solubility measurements of a variety of solid electrolytes in water and aqueous solutions in the author's laboratories are reviewed. The experimental challenge of performing such measurements with high accuracy is demonstrated using the solubility of solid sodium chloride in water at near-ambient temperatures as a paradigm. The special difficulties of measuring low solubilities are demonstrated using Pb(II) sulfate in various aqueous solutions and Pb(II) oxide in sodium hydroxide solutions, and the usefulness of such measurements for obtaining reliable information on homogeneous reactions in solution is briefly discussed. It is also shown, using the alkali metal triflate salts as examples, that determination of the solubilities of even highly soluble salts can be problematic. Lastly, data for the solubilities of a series of sodium carboxylate salts of industrial relevance are discussed and are used to illustrate why the theoretical prediction of solid electrolyte solubilities remains such a challenge. [ABSTRACT FROM AUTHOR]

Abstract: This review details the current methods used to prepare vinyl triflates derived from 1,3-dicarbonyl compounds and describes the reactivity of such functionalized vinyl triflates. α-Ketovinyl triflates can easily and stereoselectively be produced through three different ways. Enolization and triflation is the most common route, but direct triflation with triflic anhydride could also be used, each involving different mechanisms. Direct addition of triflic acid and related sulfonic acids to triple bond offers an alternative to the previous methods. With their peculiar set of functional groups, α-ketovinyl triflates can react in four different ways. The vinyl triflate part could be engaged in coupling reactions, while the carbonyl group as well as the enone motif could be subjected to nucleophilic additions. If a proton is available next to the triflate group, eliminations could occur under basic conditions. Upon addition, fragmentations could also be possible. [Copyright &y& Elsevier]

The synthesis of C2v-symmetric resorcin[4]arenes with four triflate substituents was investigated, and a number of examples were structurally characterised by X-ray crystallography. Starting from a readily prepared resorcin[4]arene octol, the reduction in the symmetry to C2v is achieved via the known regioselective tetra-substitution reaction with tosyl chloride. The remaining four hydroxyl groups can be either converted to triflates, or protected as methoxy groups allowing clean hydrolysis of the tosylates to a tetramethoxyresorcin[4]arene tetrol, ready for further functionalisation including triflate incorporation. Synthesis and structural characterisation of the first octa(triflate)resorcin[4]arene are also reported. Aryl triflates are known to be reactive in a number of cross-coupling reactions, and thus, the triflate-resorcin[4]arenes reported herein are promising precursors for functionalisation of the upper rim of these cavitand hosts. [ABSTRACT FROM PUBLISHER]

Abstract: This study demonstrates the utility of rare-earth metal triflate catalysts (i.e., Sc(OTf)3 and In(OTf)3) in the (trans)esterification of oleic acid as well as the lipids contained within carbonized algal biomass using ethanol in the presence of water. Both catalysts are highly active between 200 and 235°C with an ethanol:fatty acid (EtOH:FA) molar ratio of 10–20:1 and showed a high tolerance for moisture. Lipids within hydrochars produced by reacting Chlorella protothecoides paste (25% solids) in high temperature water (220–250°C) were successfully converted into fatty acid ethyl esters (FAEE). The highest FAEE yields (85–98%) were obtained when hydrochars were reacted for 60min at 215°C with about 11–13mol% Sc(OTf)3, a 17–19:1 EtOH:FA molar ratio, and without water. FAEE yields remained as high as 93% in the presence of 9wt.% water. Our preliminary results warrant further work to optimize triflate-catalyzed in situ (trans)esterification at low catalyst and ethanol loadings. [Copyright &y& Elsevier]

Abstract: Novel germanium containing triflates were prepared from the reactions of trifluoromethanesulfonic acid with tetraphenylgermane (1) and digermanes (Ph3GeGeMe3 (4), Ph3GeGePh3 (5)). The improved procedures for synthesis of known organogermanium compounds (Ph4Ge (1), Ph3GeCl (2), Ph3GeGeMe3 (4), Ph3GeGePh3 (5)) were also presented. The crystal structure of Ph3GeOTf (6) and Ph2Ge(OTf)Ge(OTf)Ph2 (7) was studied by X-ray analysis. In 7 each germanium atom is pentacoordinated due to intramolecular interaction with O atom of the neighboring triflate group. [Copyright &y& Elsevier]

Abstract: A new manganese complex of the formula [Mn(tptz)(OH2)3](CF3SO3)2·EtOH, (1, where tptz =(2,4,6-tris(2-pyridyl)-1,3,5-triazine) is presented, exhibiting an excellent catalytic activity and selectivity in oxidation of various sulfides to the corresponding sulfoxides with UHP (urea hydrogen peroxide) as oxidant under air at room temperature. A modified preparation procedure produces another new manganese complex of the formula [Mn(tptz)(CH3COO)(OH2)2](CF3SO3)·3H2O (2). X-ray structures of both Mn(II) complexes, properties (elemental analysis, electrochemistry, EPR, IR, Raman, and UV–Vis spectra), as well as DFT studies results are reported. [Copyright &y& Elsevier]

Abstract: An efficient method to prepare 2,3-diarylimidazo[1,2-a]pyridines is described. The procedure involves a Suzuki cross-coupling reaction followed by a direct arylation at position 3. Imidazo[1,2-a]pyridin-2-yl triflate was identified as a suitable coupling partner, permitting access to a variety of highly functionalized 2,3-diarylimidazo[1,2-a]pyridines. [Copyright &y& Elsevier]

Abstract: An understanding of the interaction of weakly coordinating ligands with zero-valent palladium complexes is of importance to understanding the potential catalytic mechanisms and properties of these complexes. We have used a combination of multi-nuclei NMR, microanalysis and single crystal X-ray diffraction to characterize a series of tripalladium ditropylium sandwich complexes that possess one or more triflate [CF3SO3]− ligands. The influence of the strong electronic effects on the triflate ligand cause a significant change in the internal bond lengths and angles of the complexes which are coupled to systematic shifts of the tropylium 1H and 13C resonances in the NMR spectra. The use of the Advanced Light Source (ALS) permitted crystallographic characterization of only the third example of a complex containing a Pd–FBF3 bond. [Copyright &y& Elsevier]

This review describes our recent studies toward the reactivity and selectivity of mannopyranosyl uronic acid donors, which have been found to be very powerful donors for the construction of β-mannosidic linkages. [ABSTRACT FROM PUBLISHER]