Search

Organic scintillators are praised for their abundant element reserves, facile preparation procedures, and rich structures. However, the weak X‐ray attenuation ability and low exciton utilization efficiency result in unsatisfactory scintillation performance. Herein, a new family of highly efficient organic phosphonium halide salts with thermally activated delayed fluorescence (TADF) are designed by innovatively adopting quaternary phosphonium as the electron acceptor, while dimethylamine group and halide anions (I−) serve as the electron donor. The prepared butyl(2‐[2‐(dimethylamino)phenyl]phenyl)diphenylphosphonium iodide (C4‐I) exhibits bright blue emission and an ultra‐high photoluminescence quantum yield (PLQY) of 100 %. Efficient charge transfer is realized through the unique n‐π and anion‐π stacking in solid‐state C4‐I. Photophysical studies of C4‐I suggest that the incorporation of I accounts for high intersystem crossing rate (kISC) and reverse intersystem crossing rate (kRISC), suppressing the intrinsic prompt fluorescence and enabling near‐pure TADF emission at room temperature. Benefitting from the large Stokes shift, high PLQY, efficient exciton utilization, and remarkable X‐ray attenuation ability endowed by I, C4‐I delivers an outstanding light yield of 80721 photons/MeV and a low limit of detection (LoD) of 22.79 nGy ⋅ s−1. This work would provide a rational design concept and open up an appealing road for developing efficient organic scintillators with tunable emission, strong X‐ray attenuation ability, and excellent scintillator performance. [ABSTRACT FROM AUTHOR]

Using triterpenoid betulin as an example, a convenient method for the synthesis of 5,6-dihydropyran derivatives containing a nor-triterpenoid fragment at position 4 was proposed. The method involves the reaction of lupane triterpenoids with paraformaldehyde in dioxane in the presence of sulfuric acid. Approaches to the synthesis of triterpene derivatives of 5,6-dihydropyran-2-one and penta-2,4-dienoic acid were developed based on the obtained 4-(3,28-diacetoxy-20,29,30-tri-nor-lupan-19-yl)-5,6-dihydropyran. Triterpene-substituted penta-2,4-dienoic acid heated with triphenylphosphonium triflate formed a quaternary phosphonium salt, which showed cytotoxicity against human cancer cells MCF-7 (breast cancer) and HCT116 (colon cancer) with IC50 4–19 µmol L−1, with its activity against these cell lines being superior to the activity of the comparison drug camptothecin. [ABSTRACT FROM AUTHOR]

A novel metal-free synthesis of 3-substituted isocoumarins through a sequential O-acylation/Wittig reaction has been established. The readily accessible (2-carboxybenzyl)-triphenylphosphonium bromide and diverse chlorides produced various 1H-isochromen-1-one in the presence of triethylamine, employing sequential O-acylation and an intramolecular Wittig reaction of acid anhydride. Reactions using these facile conditions have exhibited high functional group tolerance and excellent yields (up to 90%). Moreover, the fluorescence properties of isocoumarin derivatives were evaluated at the theoretical and experimental levels to determine their potential application in fluorescent materials. These derivatives have good photoluminescence in THF with a large Stokes shift and an absolute fluorescence quantum yield of up to 14%. [ABSTRACT FROM AUTHOR]

Heteroarylphosphonium salts are easily accessible, versatile intermediates in functionalization of N‐heterocycles. Direct C−C bond formation by net substitution of the phosphine has so far required transition metal catalysts, the use of strongly basic reagents or redox catalysis. Here we describe a C−C bond formation in direct reactions of benzothiazol‐2‐yl‐phosphonium and pyridin‐4‐yl‐phosphonium salts and nitrile anions which, together with the direct synthesis of phosphonium salts from benzothiazoles and pyridines, constitutes an efficient and simple two‐step protocol for C−H functionalization of these heterocycles under mild conditions. [ABSTRACT FROM AUTHOR]

The effective chemical valorization of CO2 by means of its conversion into valuable products is now more than ever a topic of considerable interest. It is on that basis that herein we have chosen the conversion of CO2 and epoxides to cyclic carbonates as a convenient route to achieve this goal. A new bifunctional (Lewis acid/nucleophile) heterogeneous material, TSP‐AlCl‐PhospBr, was designed in order to guarantee a close proximity between the two active sites that can cooperate to the activation and opening of the epoxide ring. The prepared copolymer has been extensively characterized using various spectroscopic and analytical techniques. As a heterogeneous catalyst, it enables efficient chemical conversion of CO2 and epoxides, even at low temperatures, down to 30 °C, without the use of solvents. In particular, the catalyst demonstrates high turnover numbers (TON) and frequency values (TOF). Recyclability studies on TSP‐AlCl‐PhospBr have shown its stability and reusability for consecutive cycles without the need of reactivation procedures. [ABSTRACT FROM AUTHOR]

The reaction of (ortho-acetalaryl)arylmethanols with various phosphines PR1R2R3 (R1 = R2 = R3 = Ph; R1 = R2 = Ph, R3 = Me and R1 = R2 = Me, R3 = Ph) under acidic conditions (e.g., HCl, HBF4, TsOH) unexpectedly led to the formation of (10-hydroxy-9,10-dihydroanthr-9-yl)phosphonium salts instead of the corresponding anthryl phosphonium salts. The cyclization occurred according to the Friedel–Crafts mechanism but without the usually observed Bradsher dehydration, giving cyclic products in the form of cis/trans isomers and their conformers. In case of electron-rich and less-hindered dimethylphenylphosphine, all four stereoisomers were recorded in 31P{1H} NMR spectra, while for the other phosphines, only the two most stable cis/trans stereoisomers were detected. This study was supported by DFT and NCI calculations in combination with FT-IR analysis. [ABSTRACT FROM AUTHOR]

Photocatalytic C−H bond phosphonioethylation of aldehydes with vinylphosphonium bromide has been developed. Various β‐phosphonioalkylketones are synthesized from readily available aldehydes under neutral conditions. Mechanistic studies suggest that C−H activation of aldehydes occurs through hydrogen‐atom transfer by a bromine radical and that an alcoholic additive, which showed marked effects in increasing the efficiency of the reaction, is involved in the reaction as a proton source. [ABSTRACT FROM AUTHOR]

(2-Methyl-3-oxoisoindolin-1-yl)triphenylphosphonium tetrafluoroborate has been successfully synthesized from Ph3PHBF4 and 3-hydroxy-2-methylisoindolin-1-one. It undergoes smoothly Wittig olefination with a variety of aldehydes when using DBU or t-BuOK as a base to furnish 3-(alkylidene)-2-methyisoindolin-1-ones in 35–93% yields with the stereoselectivity being mostly favorable to (E)-isomer. [ABSTRACT FROM AUTHOR]

Crystalline diphosphonium iodides [MeR2P‐spacer‐R2Me]I with phenylene (1, 2), naphthalene (3, 4), biphenyl (5) and anthracene (6) as aromatic spacers, are photoemissive under ambient conditions. The emission colors (λem values from 550 to 880 nm) and intensities (Φem reaching 0.75) are defined by the composition and substitution geometry of the central conjugated chromophore motif, and the anion‐π interactions. Time‐resolved and variable‐temperature luminescence studies suggest phosphorescence for all the titled compounds, which demonstrate observed lifetimes of 0.46–92.23 μs at 297 K. Radiative rate constants kr as high as 2.8×105 s−1 deduced for salts 1–3 were assigned to strong spin‐orbit coupling enhanced by an external heavy atom effect arising from the anion‐π charge‐transfer character of the triplet excited state. These rates of anomalously fast metal‐free phosphorescence are comparable to those of transition metal complexes and organic luminophores that utilize triplet excitons via a thermally activated delayed fluorescence mechanism, making such ionic luminophores a new paradigm for the design of photofunctional and responsive molecular materials. [ABSTRACT FROM AUTHOR]

A novel metal-free synthesis of 3-substituted isocoumarins through a sequential O-acylation/Wittig reaction has been established. The readily accessible (2-carboxybenzyl)-triphenylphosphonium bromide and diverse chlorides produced various 1H-isochromen-1-one in the presence of triethylamine, employing sequential O-acylation and an intramolecular Wittig reaction of acid anhydride. Reactions using these facile conditions have exhibited high functional group tolerance and excellent yields (up to 90%). Moreover, the fluorescence properties of isocoumarin derivatives were evaluated at the theoretical and experimental levels to determine their potential application in fluorescent materials. These derivatives have good photoluminescence in THF with a large Stokes shift and an absolute fluorescence quantum yield of up to 14%.

Phosphonium‐based compounds gain attention as promising photofunctional materials. As a contribution to the emerging field, we present a series of donor‐acceptor ionic dyes, which were constructed by tailoring phosphonium (A) and extended π‐NR2 (D) fragments to an anthracene framework. The alteration of the π‐spacer of electron‐donating substituents in species with terminal −+PPh2Me groups exhibits a long absorption wavelength up to λabs=527 nm in dichloromethane and shifted the emission to the near‐infrared (NIR) region (λ=805 nm for thienyl aniline donor), although at low quantum yield (Φ<0.01). In turn, the introduction of a P‐heterocyclic acceptor substantially narrowed the optical bandgap and improved the efficiency of fluorescence. In particular, the phospha‐spiro moiety allowed to attain NIR emission (797 nm in dichloromethane) with fluorescence efficiency as high as Φ=0.12. The electron‐accepting property of the phospha‐spiro constituent outperformed that of the monocyclic and terminal phosphonium counterparts, illustrating a promising direction in the design of novel charge‐transfer chromophores. [ABSTRACT FROM AUTHOR]

A novel representative of sodium 3,4,5-triaryl-1,2-diphosphacyclopentadienide containing a chloro substituent in the meta-position of the aryl groups was obtained with a high yield based on the reaction of tributyl(1,2,3-triarylcyclopropenyl)phosphonium bromide and sodium polyphosphides. Further reaction of sodium 3,4,5-tris(3-chlorophenyl)-1,2-diphosphacyclopentadienide with [FeCp(η6-C6H5CH3)][PF6] complex gives a new 3,4,5-tris(3-chlorophenyl)-1,2-diphosphaferrocene. The electrochemical properties of 3,4,5-tris(3-chlorophenyl)-1,2-diphosphaferrocene were studied and compared to 3,4,5-tris(4-chlorophenyl)-1,2-diphosphaferrocene. It was found that the position of the chlorine atom on the aryl fragment has an influence on the reduction potential of 1,2-diphosphaferrocenes, while the oxidation potentials do not change.

The synthesis of new phosphonium salts derived from Michael acceptors via a one-pot reaction process and the study of their NMR characteristics is described. The simple and rapid 1,4 addition of triphenylphosphine to the Michael acceptors in the presence of HBr (48%) (5 equivalents) was carried out at room temperature to give the corresponding phosphonium salts with excellent yields. [ABSTRACT FROM AUTHOR]

This comprehensive review, covering the years 1968–2022, is not only a retrospective investigation of a certain group of linearly fused aromatics, called acenes, but also a presentation of the current state of the knowledge on the synthesis, reactions, and applications of these compounds. Their characteristic feature is substitution of the aromatic system by one, two, or three organophosphorus groups, which determine their properties and applications. The (PIII, PIV, PV) phosphorus atom in organophosphorus groups is linked to the acene directly by a P-Csp2 bond or indirectly through an oxygen atom by a P-O-Csp2 bond. [ABSTRACT FROM AUTHOR]

Functional porous organic polymers (POPs) have been widely developed as heterogeneous catalysts for carbon dioxide (CO 2 ) conversion. However, the integration of multifunctional active sites into POPs remains a major challenge. Herein, a facile postsynthesis modification strategy was explored to fabricate metalloporphyrin- and phosphonium-bifunctionalized POPs (TAPPM-PTBAR) as the heterogeneous catalysts for CO 2 conversion. The as-developed catalysts were characterized in detail using various techniques. The results illustrated that the novel POP catalysts featured abundant Lewis acid metal centers, nucleophilic active sites, and phosphonium cation. These features enabled the catalyst to immobilize CO 2 under mild and solvent-free conditions. The synergistic effect of cobalt as a Lewis acid site and halide anion as a bifunctional nucleophile site enhances the catalysis performance of TAPPM-PTBAR. Combining the experimental results and density functional theory calculation, a plausible reaction mechanism involving hydrogen bonding and Co 3+ center for epoxides was proposed. Considering its good reusability and substrate expansibility, the developed TAPPCo 3+ -PTBANH 2 demonstrated great potential as a robust heterogeneous catalyst for the efficient utilization of C1 resources.

Phosphonium salts and their corresponding phosphabetaines—ω-phosphonioalkanoates—with a large number of methylene units were obtained on the basis of the reaction of triphenylphosphine and ω-bromoalkanecarboxylic acids. Structure and composition of the reaction products was proved using IR and NMR spectroscopy, X-ray diffraction analysis, and elemental analysis data. For a number of compounds, antimicrobial activity and thermal stability were studied. [ABSTRACT FROM AUTHOR]

An efficient method for the phosphine-catalyzed bisaddition of P(O)H compounds and cyclic imides to divinyl sulfone has been developed. The reaction proceeds under mild conditions and leads to the formation of the corresponding target products in high yield. The mono- and bisphosphonium salts have been obtained in high yield on the basis of divinyl sulfone. [ABSTRACT FROM AUTHOR]

The direct transformation of Morita–Baylis–Hillman (MBH) adducts into molecules of interest is a crucial process wherein allylic hydroxy-protected or halogenated MBH adducts are commonly preferred. Herein, we report an azidophosphonium salt (AzPS)-catalysed straight forward protocol for synthesising structurally demanding (E)/(Z)-cinnamyl-1H-1,2,3-triazoles and halomethylcoumarins from MBH adducts. The novel methodology, efficient catalyst, and direct utilization of MBH adducts under mild reaction conditions qualify the reported procedures as powerful synthetic tools.

This comprehensive review, covering the years 1968–2022, is not only a retrospective investigation of a certain group of linearly fused aromatics, called acenes, but also a presentation of the current state of the knowledge on the synthesis, reactions, and applications of these compounds. Their characteristic feature is substitution of the aromatic system by one, two, or three organophosphorus groups, which determine their properties and applications. The (PIII, PIV, PV) phosphorus atom in organophosphorus groups is linked to the acene directly by a P-Csp2 bond or indirectly through an oxygen atom by a P-O-Csp2 bond.

Liquid–liquid equilibrium data on butyric acid (BA) extraction by new ionic liquid (IL) tetradecyl(trihexyl)phosphonium neodecanoate ([C14C6C6C6P][NDec]) are presented and correlated using a model developed earlier. Extraction performance of the new IL is comparable with that of previously tested phosphonium ILs with decanoate and phosphinate anions. High loading of IL with BA of more than 12 BA molecules per one IL ion pair was achieved at aqueous BA concentration of 1.2 mol dm−3. The overall extraction mechanism includes competitive extraction of BA and water, and coextraction of BA with water. Both these sub-mechanisms act simultaneously, the first one dominates below IL loading by acid of 2 and the second one above this value. Dynamic viscosity of water saturated [C14C6C6C6P][NDec] is slightly higher compared to a similar IL with decanoate anion [C14C6C6C6P][Dec] (104 and 96 mPa s). However, at 298 K dried [C14C6C6C6P][Dec] is solid, while [C14C6C6C6P][NDec] is liquid even below 253 K which is a great advantage. Viscosity of equilibrium organic phases shows a maximum at IL loading by BA of about 1.6 which corresponds to the minimal solute (BA + water) content and maximal molar fraction of IL due to water release from the solvent. [ABSTRACT FROM AUTHOR]

The nucleophilic addition reactions of tertiary phosphines and unsaturated carboxylic acids have led to the formation of mono- and dicarboxylate phosphabetaines containing an asymmetric carbon atom. The data of 1D and 2D NMR spectroscopy have revealed the presence of diastereotopic geminal protons of the CH2 group adjacent to the chiral center in the obtained compounds. The values of spin-spin coupling constants of the vicinal hydrogen atoms have coincided with the dihedral angles values (X-ray diffraction analysis data). [ABSTRACT FROM AUTHOR]

• POPs functionalized by Azo and phosphonium units were fabricated for organic dyes removal. • Azo-POP exhibits extraordinary adsorption capacity towards anion dyes. • The removal efficiency of Congo Red (CR) could reach 100 % in 30 s. • The adsorption capacity of Azo-POP is photo-tunable. Adsorption has been recognized as a highly economical and feasible technique for the removal of organic pollutants from water. Thus, the search for novel and efficient porous adsorbents for water purification is a crucial and pressing task. Here, a new family of azobenzene- and phosphonium-functionalized porous organic polymers (Azo-POPs) were fabricated via a post-synthesis approach. By taking advantage of the photo-tunable transformation of Azo units, the adsorption behaviors of two isomers of Azo-POP, trans- Azo-POP and cis- Azo-POP, were examined. The results demonstrated that both of Azo-POPs exhibited extraordinary adsorption capacity and adsorption rate towards anionic dyes due to their porous structure, cation-charged and hydrophilic skeleton. However cis- Azo-POP afforded much more efficient adsorption performances. The removal efficiency of Congo red (CR) could reach 100 % in 30 s, and the maximum adsorption capacity was as high as 1376.8 mg g−1, surpassing most previously reported adsorbents. The pseudo-second-order rate constant of cis- Azo-POP was 16.9153 g mg−1min−1. Additionally, Azo-POP adsorbents could be easily regenerated and reused over five cycles without any loss of adsorption capability. Therefore, the study suggests a universal platform for the fabrication of functional POP materials, which will find great potential in the fields of industrial wastewater treatment and catalysis. [ABSTRACT FROM AUTHOR]

New silver nanocomposites based on polysulfones of 2,2-diallyl-1,1,3,3-tetraethylguanidiniumchloride [poly(AGC–SO2)], tris(diethylamino)diallylaminophosphonium tetrafluoroborate [poly(DAAP–BF4–SO2)] and chloride [poly(DAAP–Cl–SO2)] have been developed. UV-spectroscopy, SEM and XRD techniques were used to characterize the formation of silver nanoparticles in copolymers. Antibacterial action of new silver nanocomposites on S. epidermidis 33 and Escherichia coli (planktonic cells and biofilms) was studied. The silver nanocomposites strongly inhibited biofilms formation of S. epidermidis 33 and Escherichia coli. The silver nanocomposites based on phosphonium polysulfones have a significant cytotoxic activity against RD and MS line cells. [ABSTRACT FROM AUTHOR]

Quaternary phosphonium salts have been extensively used in organic synthesis as Lewis acid organocatalysts. This review covers recent applications of phosphonium salts as Lewis acidic catalysts for Mannich, Strecker, and Friedel‐Crafts reactions for the formation of C−C bonds, annulation reactions, etc., allowing the construction of structurally diverse and synthetically useful architectures. [ABSTRACT FROM AUTHOR]

The adduct of acetylenedicarboxylic acid and the water-soluble 1,3,5-triaza-7-phosphaadamantane (PTA, 1) in 1:2 molar ratio, was synthesized both in aqueous solution and under anhydrous conditions in a planetary ball mill (pbm). The resulting double phosphabetaine (2) was characterized by 1H-, 13C-, and 31P-NMR spectroscopy, ESI-mass spectroscopy, and elemental analysis, furthermore, its solid-state structure was determined by single crystal X-ray diffraction. SXRD also revealed that in aqueous solution 2 reacted with AgSO3CF3 to yield a 2 D polymer. [ABSTRACT FROM AUTHOR]

This paper has been supported by the Kazan Federal University Strategic Academic Leadership Program ('PRIORITY-2030'). HRMS data were obtained in the CSF-SAC FRC KSC RAS by support of the State Assignment of the Federal Research Center "Kazan Scientific Center", Russian Academy of Sciences. A.D.V, conducted studies of anticancer activity with financial support form the government assignment for FRC Kazan Scientific Center of RAS., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

New carboxylate phosphabetaines were synthesized from 3-(diphenylphosphino)propionic acid and unsaturated amides. Alkylation of the synthesized carboxylate phosphabetaines with haloalkyles was studied. In vitro biological activity of the synthesized phosphonium salts was evaluated. [ABSTRACT FROM AUTHOR]

It has been shown for a wide range of epoxy compounds that their interaction with triphenylphosphonium triflate occurs with a high chemoselectivity and leads to the formation of (2-hydroxypropyl)triphenylphosphonium triflates 3 substituted in the 3-position with an alkoxy, alkylcarboxyl group, or halogen, which were isolated in a high yield. Using the methodology for the disclosure of epichlorohydrin with alcohols in the presence of boron trifluoride etherate, followed by the substitution of iodine for chlorine and treatment with triphenylphosphine, 2-hydroxypropyltriphenylphosphonium iodides 4 were also obtained. The molecular and supramolecular structure of the obtained phosphonium salts was established, and their high antitumor activity was revealed in relation to duodenal adenocarcinoma. The formation of liposomal systems based on phosphonium salt 3 and L-α-phosphatidylcholine (PC) was employed for improving the bioavailability and reducing the toxicity. They were produced by the thin film rehydration method and exhibited cytotoxic properties. This rational design of phosphonium salts 3 and 4 has promising potential of new vectors for targeted delivery into mitochondria of tumor cells.

It was shown that the direction of the reaction of 2-methyl-1,4-naphthoquinone with H-phosphonium salts obtained from diphenylphosphine and trifluoromethanesulfonic or trifluoroacetic acids depends on the nature of the anion. Structure of the obtained mono- and diphosphinates, as well as the quasi-phosphonium salt, was established by NMR spectroscopy and single crystal X-ray diffraction methods. [ABSTRACT FROM AUTHOR]

In this work, a phosphonate‐functionalized ionic liquid, 4‐(diethoxyphosphoryl)butyl triphenylphosphonium hexafluorophosphate (PFIL) has been synthesized and characterized by FTIR, NMR and HRMS spectra. The viscosities (η) and conductivities (κ) of three binary mixtures of PFIL with acetonitrile (ACN), N,N‐dimethylformamide (DMF), and dimethyl sulfoxide (DMSO), respectively, were investigated in the temperature range from 293.15 to 343.15 K at atmospheric pressure. Solid PFIL dissolves in all these polar solvents within the concentrations studied (mole fraction of PFIL from 0.01 to 0.14). The experimental studies indicate that the viscosities of the three binary mixtures decrease in the following order: [PFIL(1) + DMSO(2)] > [PFIL(1) + DMF(2)] > [PFIL(1) + ACN(2)], while as expected, the conductivities increase in the following order: [PFIL(1) + ACN(2)]>[PFIL(1) + DMF(2)]>[PFIL(1) + DMSO(2)]. The conductivities as a function of temperature have been well correlated by Vogel‐Fulcher‐Tammann (VFT) and Arrhenius equations, while viscosities can be better fitted by using VFT equation. The dependence of conductivity on concentration for the studied systems is well represented by Casteel‐Amis equation. Phosphonate‐functionalized phosphonium ionic liquid was synthesized. Viscosities and conductivities of three binary mixtures of ionic liquid with acetonitrile, N,N‐dimethylformamide, and dimethyl sulfoxide were investigated. Temperature dependence of conductivities and viscosities can be described by Vogel‐Fulcher‐Tammann (VFT) and Arrhenius equations. The dependence of conductivity on concentration is well represented by Casteel–Amis equation. [ABSTRACT FROM AUTHOR]

• The application of a new phosphonium-carbon-based phase-transfer catalyst (PTC) synthetized by mechanochemical approach is studied. • The new heterogeneous PTC is fully characterized and used for S N 2 type reaction of NaSCN with variously substituted benzyl bromides. • Using 5mol% catalyst in water can result in over 99% conversion of the reaction. • Being heterogeneous, the phosphonium-carbon-based PTC catalyst can be easily recovered in an aqueous solution and recycled without any loss in efficiency even after five runs. The use of phosphonium-carbon-based PTC as a catalyst in water solution is here described and its performances are discussed. The synthesis is realized via a mechanochemical process in solvent-free conditions respecting most of the green metrics for a sustainable procedure. The heterogeneous phase-transfer catalyst is fully characterized and used for S N 2-type reaction of NaSCN with variously substituted benzyl bromides. The reaction proceeds with high efficiency in the presence of 5mol% of catalyst in water up to >99% of conversion. The catalyst can be easily recycled without losing productivity providing a green procedure. [Display omitted] [ABSTRACT FROM AUTHOR]

In their Research Article (e202305108), Andreas Steffen, Andrey Belyaev, Pi-Tai Chou, Igor O. Koshevoy et al. show that the anion- interactions in crystalline diphosphonium iodides induce unusually fast room temperature triplet emission, which is associated with the external heavy atom effect and anion- charge-transfer character of the excited states. Anion- Interactions, Charge Transfer, Crystal Engineering, Phosphonium Salt, Phosphorescence Keywords: Anion- Interactions; Charge Transfer; Crystal Engineering; Phosphonium Salt; Phosphorescence EN Anion- Interactions Charge Transfer Crystal Engineering Phosphonium Salt Phosphorescence 1 1 1 09/01/23 20230904 NES 230904 B Harvesting organic phosphorescence b is essential for many fields in energy and materials sciences related to light generation. [Extracted from the article]

Anion- Interactions, Charge Transfer, Crystal Engineering, Phosphonium Salt, Phosphorescence In their Research Article (e202305108), Andreas Steffen, Andrey Belyaev, Pi-Tai Chou, Igor O. Koshevoy et al. show that the anion- interactions in crystalline diphosphonium iodides induce unusually fast room temperature triplet emission, which is associated with the external heavy atom effect and anion- charge-transfer character of the excited states. Keywords: Anion- Interactions; Charge Transfer; Crystal Engineering; Phosphonium Salt; Phosphorescence EN Anion- Interactions Charge Transfer Crystal Engineering Phosphonium Salt Phosphorescence 1 1 1 08/31/23 20230904 NES 230904 B Harvesting organic phosphorescence b is essential for many fields in energy and materials sciences related to light generation. [Extracted from the article]

The title hydrated salt, C26H32O3P+·Cl−·H2O, contains four different substituents (H, alkyl, aryl, and biaryl) on the P atom. The P—H hydrogen atom of the phosphonium ion was located in a difference Fourier map and refined without imposing additional restraints. In the crystal, the Cl− ions and water molecules are linked by pairs of Owater—H...Cl− hydrogen bonds and further linked to the phosphonium cation by P—H+...Cl− and CAr/OMe—H...Owater hydrogen bonds to form an infinite one-dimensional chain along the [010] direction.

We have described earlier that in aqueous solutions, the reaction of 1,3,5-triaza-7-phosphaadamantane (PTA) with maleic acid yielded a phosphonium-alkanoate zwitterion. The same reaction with 2-methylmaleic acid (citraconic acid) proceeded much slower. It is reported here, that in the case of glutaconic and itaconic acids (constitutional isomers of citraconic acid), formation of the corresponding phosphabetaines requires significantly shorter reaction times. The new phosphabetaines were isolated and characterized by elemental analysis, multinuclear NMR spectroscopy and ESI-MS spectrometry. Furthermore, their molecular structures in the solid state were determined by single crystal X-ray diffraction (SC-XRD). Synthesis of the phosphabetaines from PTA and unsaturated dicarboxylic acids was also carried out mechanochemically with the use of a planetary ball mill, and the characteristics of the syntheses in solvent and under solvent-free conditions were compared. In aqueous solutions, the reaction of the new phosphabetaines with Ag(CF3SO3) yielded Ag(I)-based coordination polymers. According to the SC-XRD results, in these polymers the Ag(I)-ion coordinates to the N and O donor atoms of the ligands; however, Ag(I)-Ag(I) interactions were also identified. The Ag(I)-based coordination polymer (CP1.2) formed with the glutaconyl derivative of PTA (1) showed considerable antimicrobial activity against both Gram-negative and Gram-positive bacteria and yeast strains

The integration of synergic hydrogen bond donors and nucleophilic anions that facilitates the ring-opening of epoxide is an effective way to develop an active catalyst for the cycloaddition of CO2 with epoxides. In this work, a new heterogeneous catalyst for the cycloaddition of epoxides and CO2 into cyclic carbonates based on dual hydroxyls-functionalized polymeric phosphonium bromide (PQPBr-2OH) was presented. Physicochemical characterizations suggested that PQPBr-2OH possessed large surface area, hierarchical pore structure, functional hydroxyl groups, and high density of active sites. Consequently, it behaved as an efficient, recyclable, and metal-free catalyst for the additive and solvent free cycloaddition of epoxides with CO2. Comparing the activity of PQPBr-2OH with that of the reference catalysts based on mono and non-hydroxyl functionalized polymeric phosphonium bromides suggested that hydroxyl functionalities in PQPBr-2OH showed a critical promotion effect on its catalytic activity for CO2 conversion. Moreover, PQPBr-2OH proved to be quite robust and recyclable. It could be reused at least ten times with only a slight decrease of its initial activity.

The structure of tetraphenylphosphonium tetrakis(trimethylsilanolato)ferrate(III), [(C6H5)4P][Fe(OSi(CH3)3)4], has tetragonal (I-4) symmetry, and was refined as an inversion twin. It is an ionic compound consisting of a tetraphenylphosphonium cation and a tetrakis(trimethylsilanolato)ferrate(III) anion. The crystal structure comprises the two ionic species each centered on a -4 symmetry element and contributing a fourth of its structure to the asymmetric unit. Each is surrounded by counter-ions on all sides. The cation contains a central phosphorous atom bound to four phenyl groups in a tetrahedral arrangement, while the anion contains a central iron(III) atom tetrahedrally coordinated by four trimethylsilanolato ligands.