Pyridinium Trifluoromethanesulfonate Research Articles

Enhancing Organic–Inorganic Perovskite Thin Film Crystallization via Vapor–Solid Reaction by Modifying PbI2 Precursors Films with Pyridinium Trifluoromethanesulfonate

The vapor–solid reaction technique holds potential for producing large‐scale organic–inorganic perovskite films, using a two‐step deposition process. The sucess of perovskite formation heavily relies on the crystallization of lead iodide (PbI2) precursor films. However, the high crystallinity of PbI2 can hinder organic vapors' diffusion and negatively affecting the solar cells by increasing charge recombination and accelerating degradation. To address this, pyridinium trifluoromethanesulfonate (PTFS) is introduced into the PbI2 precursor solution to control the nucleation and growth of PbI2 films. PTFS has been found to effectively suppresses PbI2 crystallization and enhance the integration of formamidinium ion (FA+) through hydrogen bonding, facilitating the full transformation of PbI2 into perovskite. It also minimizes defect formation by interacting with uncoordinated Pb2+ and FA+ ions. These modifications have significantly enhanced power conversion efficiency (PCE), reaching up to 21.19%, and the devices have maintained 93% of their initial performance after 1580 h of exposure to air.

Well-defined core-shell nanostructural block copolymer supported recyclable Bronsted acidic ionic liquid catalyst for the synthesis of biodiesel

A series of Bronsted acidic ionic liquid catalysts was synthesized by anchoring 1-(3-sulfopropyl)pyridinium trifluoromethanesulfonate onto the stable core-shell micelles, which were formed by cross-linking various chain length ratios PS-b-P4VP in toluene with 1,4-dibromobutane. These catalysts display excellent catalytic activity in the esterification or transesterification of palmitic acid or glycerol tripalmitate with methanol or ethanol to synthesize the biodiesel (yield > 99%) in the presence of 4 mol% catalyst loading. Furthermore, the biodiesel yield was maintained about 90% even with a water content of 10 wt% corresponding to the total weight of reaction system. More importantly, these supported catalysts with core-shell structure could be recycled for 5–6 times (5 cycles: yield 89.3%, 6 cycles: yield 84%) only by simple centrifugation without appreciating activity decrease.

Biodegradation and toxicity of emerging contaminants: Isolation of an exopolysaccharide-producing Sphingomonas sp. for ionic liquids bioremediation.

Ionic liquids (ILs) have been characterized as contaminants of emerging concern (CEC) that often resist biodegradation and impose toxicity upon environmental release. Sphingomonas sp. MKIV has been isolated as an extreme microorganism capable for biodegradation of major classes of ILs. Six imidazolium-, pyridinium- and ammonium-based ILs (pyridinium trifluoromethanesulfonate [Py][CF3SO3], 1-(4-pyridyl)pyridinium chloride [1-4PPy][Cl], 1-butyl-3-methylimidazolium bromide [BMIM][Br], 1-butyl-3-methylimidazolium methanesulfonate [BMIM][MeSO4], tetrabutylammonium iodide [n-Bu4N][I] and tetrabutylammonium hexafluorophosphate [n-Bu4N][PF6]) were used for microbial growth. The strain achieved 91% and 87% removal efficiency for cultures supplemented with 100 mg L-1 of [BMIM][MeSO4] and [n-Bu4N][I] respectively. The metabolic activity of MKIV was inhibited following preliminary stages of cultures conducted using [BMIM][MeSO4], [BMIM][Br], [Py][CF3SO3] and [n-Bu4N][PF6], indicating potential accumulation of inhibitory metabolites. Thus, a comprehensive toxicological study of the six ILs on Aliivibrio fischeri, Daphnia magna and Raphidocelis subcapitata was conducted demonstrating that the compounds impose moderate and low toxicity. The end-products from [BMIM][MeSO4] and [n-Bu4N][I] biodegradation were assessed using Aliivibrio fischeri, exhibiting increased environmental impact of the latter following biotreatment. MKIV produced 19.29 g L-1 of biopolymer, comprising mainly glucose and galacturonic acid, from 25 g L-1 of glucose indicating high industrial significance for bioremediation and exopolysaccharide production.

Rh(III)-Catalyzed Oxidative Annulation Leading to Substituted Indolizines by Cleavage of C(sp(2))-H/C(sp(3))-H Bonds.

Rhodium(III)-catalyzed oxidative annulation reactions of pyridinium trifluoromethanesulfonate salts with alkynes leading to substituted indolizines by cleavage of C(sp(2))-H/C(sp(3))-H bonds are developed. The starting materials are readily available, and the reactions have a broad substrate scope. This reaction overcomes some drawbacks of the previous indolizine synthetic methods and provides a new efficient route to indolizine derivatives.

Phase transitions in non-centrosymmetric pyridinium trifluoromethanesulfonate crystal: Vibrational studies

Infrared spectroscopy (4000–400cm−1) in the wide temperature range, from 11 to 473K, has been used to investigate the non-centrosymmetric pyridinium trifluoromethanesulfonate crystal, exhibiting several phase transitions. The assignments of the bands observed in the studied spectra have been proposed. The temperature dependence of the wavenumbers and the full width at half maximum (FWHM) of the bands arising from some internal vibrations of the pyridinium cation and the triflate anion have been analyzed in order to achieve a knowledge of whether these both ions are involved in the phase transitions and what is the role of these both ions in these phase transitions. The infrared measurements showed that the both ions, pyridinium cation and triflate anion are involved in the high temperature phase transitions of the order–disorder type, previously reported at 305.1 and 396.7K. They also revealed that these transitions are governed by a rotational mobility (changes in dynamical states) of both the pyridinium and triflate ions. Our results show that the multiple structures of the νNH and νND bands observed in the studied infrared spectra is due to the Fermi resonance interaction between the stretching vibration of the N–H⋯O hydrogen bond and the overtones and combinations of the internal vibrations of the pyridinium cation.

The crystal structure and the phase transitions of pyridinium trifluoromethanesulfonate

The calorimetric and optical studies and the structural properties of pyridinium trifluoromethanesulfonate (abbreviated as PyHOTf) are reported. A sequence of four fully reversible solid–solid phase transitions, at 223.0, 309.0, 359.9 and 394.3 K, has been discovered. The phase transition sequence was confirmed by x-ray diffraction data. The crystal structures of three phases (V, IV and III) have been determined from the single crystal x-ray diffraction data. Structural properties of the high temperature phases are characterized using powder x-ray diffraction data measured in the 290–425 K temperature range. The structural changes triggered by the temperature change are discussed in relation to the phase transitions. Two low temperature phases (V and IV) belong to the P43212 space group of the tetragonal system. The intermediate phases (III and II) are monoclinic and the prototype high temperature phase (I) is a pseudo-cubic (tetragonal) one. The low temperature phases (V and IV) are well ordered. The crystal structure of intermediate (III and II) and prototype (I) phases are characterized by high disorder of the pyridinium cations and triflate anions.

Synthesis of 5‐Heteroaryl‐ and 5,7‐Bis(heteroaryl)azulenes by Electrophilic Substitution of 1,3‐Di‐tert‐Butylazulene with Triflates of N‐Containing Heterocycles

AbstractAn efficient synthesis of 5‐heteroaryl‐ and 5,7‐bis(heteroaryl)azulene derivatives was established for first time. The reaction proceeded through electrophilic substitution of 1,3‐di‐tert‐butylazulene (1) with the triflates of N‐containing heterocycles, in the presence of excess heterocycles, in good yields. The presumed intermediates, 5‐(dihydroheteroaryl)azulene derivatives were also available by the reaction with several N‐containing heterocycles in the presence of Tf2O under milder reaction conditions. Treatment of the 5‐(dihydroheteroaryl)azulene derivatives with KOH readily gave the desired 5‐(heteroaryl)azulene derivatives. Unexpectedly, N‐(5‐azulenyl)pyridinium triflate 17 was also obtained by the reaction of 1 with (trifluoromethylsulfonyl)pyridinium trifluoromethanesulfonate (TPT). 5‐Heteroaryl‐ and 5,7‐bis(heteroaryl)azulene derivatives exhibited a significant color change in acetic acid compared to those in dichloromethane due to the development of intramolecular charge‐transfer (CT) absorption bands. The redox behavior of these new azulene derivatives was examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV).

Electrophilic ipso‐Substitution and Some Unique Reaction Behavior of 1,3,6‐Tri‐tert‐butylazulene

AbstractElectrophilic ipso‐substitution reactions between 1,3,6‐tri‐tert‐butylazulene (2) and several electrophilic reagents were examined. Friedel–Crafts and Vilsmeier reactions of 2 gave the corresponding ipso‐substitution products in moderate to excellent yields. One of the ipso‐substitution products, 1,6‐di‐tert‐butyl‐3‐formylazulene (5), was converted in high yield into the synthetically more useful azulene derivative 1,6‐di‐tert‐butylazulene (1) by decarbonylation on treatment with pyrrole in acetic acid. Treatment of 2 with N‐[(trifluoromethyl)sulfonyl]pyridinium trifluoromethanesulfonate (TPT) unexpectedly afforded 1‐trifluoromethylthioazulene 10 and 1(8H)‐azulenone 11. Compound 2 also reacted with tetracyanoethylene (TCNE) to give an excellent yield of cycloaddition product 13, rather than the ipso‐substitution reaction product.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Synthesis, homopolymerization, and block copolymerization ofN-ethyl-2-ethynyl-pyridinium trifluoromethanesulfonate with styrene and butadiene

A novel acetylenic monomer 2-N-ethyl pyridinium trifluoromethane sulfonate (2EPyEtTf) was synthesized and polymerized. Diblock copolymers of 2EPyEtTf with styrene and with butadiene were prepared. Initiation of the polymerization by living anionic polystyryl - -Li + and polybutadienyl - -Li + (Scheme 1) resulted in polystyrene-block-poly(N-ethyl-2-ethynylpyridinium trifluoromethanesulfonate) (PS 57 PA 8 ), and polybutadiene-block-poly(N-ethyl-2-ethynylpyridinium trifluoromethanesulfonate)(PB 30 PA 8 ). These amphiphilic block molecules contain rigid, conjugated, and strongly hydrophilic polyacetylene chain fragments attached to hydrophobic polystyrene or flexible polybutadiene chain fragments. The structure of these copolymers was studied by FTIR, UV-visible, and NMR spectroscopy. GPC and viscometry were also used to obtain information on the molecular mass and the molecular mass distribution. Thermal behavior was investigated by means of TGA and DSC. Both block copolymers were shown to form stable monolayers at the air-water interface. The positively charged rigid polyacetylene portion of the copolymer is believed to be partially submerged, while the more flexible hydrophobic chains are forced out of the water. Multilayers of PB 30 PA 8 deposited using the Langmuir-Blodgett technique were found to be less uniform than in the case of the previously reported polystyrene-block-poly(2E-PyMeTf)(PS 12 PA 4 ) copolymer (Balogh et al., Macromolecules, 29, 1996). Polycation-polyanion self-assembly deposition was also investigated, using polystyrenesulfonate (PSS) as polyanion. While PS 57 PA 8 /ASS layer-by-layer deposition was not uniform, it was found that PB 30 PA 8 /ASS gave homogenous and stable films on hydrophilic glass substrates.

ChemInform Abstract: Total Synthesis of Cyclostellettamine C, a Bispyridinium Macrocyclic Alkaloid Having Muscarinic Acetylcholine Receptor Antagonistic Activity.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Total synthesis of cyclostellettamine C, a bispyridinium macrocyclic alkaloid having muscarinic acetylcholine receptor antagonistic activity

Cyclostellettamine C (1), a bispyridinium macrocyclic compound having muscarinic acetylcholine receptor antagonistic activity, was synthesized by the stepwise ring closure method via 3-(13-hydroxytridecyl)-1-[13-(3-pyridyl)tridecyl]pyridinium trifluoromethanesulfonate (21). Through this study, the structure of naturally originating 1 was synthetically and biologically confirmed.

Synthesis of Novel Electron Acceptor, 2,5-Bis[4′-(dimethylamino)pyridinio]-3,6-difluoro-7,7,8,8-tetracyanoquinodimethane Bis(trifluoromethanesulfonate), in the Form of Charge-Transfer Complex

Abstract 2,5-Bis[4′-(dimethylamino)pyridinio]-3,6-difluoro-7,7,8,8-tetracyanoquinodimethane bis(trifluoromethanesulfonate) was obtained as a 1:1 charge-transfer complex with 4-(dimethylamino)pyridine in the reaction of 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (TCNQF4) with N-trimethylsilyl-4-(dimethylamino)pyridinium trifluoromethanesulfonate. Its first reduction potential was measured in cyclic voltammetry to be as high as 0.96 V (vs. Ag/AgCl), exceeding that of 2,5,7,7,8,8-hexacyanoquinodimethane (TCNQ(CN)2) by 0.29 V.

N-(1,1-Dihydroperfluorooctyl)Pyridinium Trifluoromethanesulfonate, a New Quaternary Ammonium Antiseptic

The synthesis and biological evaluation of N-(1,1-dihydroperfluorooctyl)pyridinium trifluoromethanesulfonate (MBR 3092-42), a highly fluorinated quaternary ammonium antiseptic, are described. The material is structurally related to cetylpyridinium chloride. It shows approximately equivalent bacteriostatic activity to cetylpyridinium chloride but somewhat less fungistatic activity. The bactericidal activity of MBR 3092-42 is slightly less than that of cetylpyridinium chloride in equal concentration in distilled water of in 10% blood serum, but is slightly greater in 80% human blood. MBR 3092-42 is also antibacterially equivalent to cetylpyridinium chloride on the resident bacterial flora of human skin. Although this new compound slowly decomposes in water at pH 7 and above, it is stable in weakly acidic aqueous or hydroalcoholic solutions. Solutions of MBR 3092-42 yield much lower surface tension values than equivalent concentrations of cetylpyridinium chloride.