Triphenylphosphine Oxide Research Articles

Thermal and Luminescent Properties of Multi-Ligand Complexes of Europium(III) with Pyrazine-2-carboxylic Acid

Eu(III) compounds with pyrazine-2-carboxylic acid and nitrogen- and phosphorus-containing neutral ligands were synthesized. Using the methods of chemical elemental and thermal analysis and IR spectroscopy, the composition of the complexes and the method of coordination of carboxylate ions were established. The most thermally stable compounds have been identified. The luminescent characteristics of complex compounds have been studied. It was found that the maximum luminescence intensity is characteristic of europium(III) pyrazinate with triphenylphosphine oxide. The morphological structure and dispersion of the complexes were determined.

Accumulation patterns and chronic toxic effects of triphenyl phosphine in Mytilus coruscus

Triphenylphosphine oxide (TPPO) as a new organophosphorus flame retardant is extensively used in the industrial and pharmaceutical fields due to its chemical stability and abundance. In marine environments, TPPO accumulates as a result of natural ecological processes. This study aimed to evaluate the accumulation process and toxicological effects of TPPO utilizing mussels (Mytilus coruscus), a species traditionally employed in marine monitoring and commonly cultivated in offshore aquaculture. GC–MS/MS was employed to quantify the accumulation of TPPO in the gill, gonad, muscle, and digestive gland tissues of mussels exposed to three sublethal concentrations (20.0, 100.0, and 500.0 μg/L) over durations of 3, 7, 14, and 28 days, as well as the examining of the chemical and molecular parameters. Results showed that the accumulation of TPPO (100.0 and 500.0 μg/L) increased throughout the 28 d of exposure, and the peak accumulation of 20.0 μg/L TPPO was detected on 14 d. Short-term TPPO exposure did not cause oxidative stress in mussels. Chronic exposure for 28 days resulted in significant oxidative damage and oxidative stress in mussels, as evidenced by elevated expression and activity of SOD, increased levels of glutathione and malondialdehyde, and upregulation of HSP70 and HSP90, metallothionein, and CYP4Y1, alongside the initiation of apoptotic cell death. TPPO exposure activated natural immune genes and disrupted lipid metabolism in mussels. This study demonstrated the persistent accumulation of TPPO in mussels, highlighting its ecotoxicological hazards and underscoring the necessity to predict the risks associated with widespread environmental exposure to TPPO.

Inside Cover: Triphenylphosphine Oxide: A Versatile Covalent Functionality for Carbon Nanotubes (Angew. Chem. Int. Ed. 46/2024)

Inside Cover: Triphenylphosphine Oxide: A Versatile Covalent Functionality for Carbon Nanotubes (Angew. Chem. Int. Ed. 46/2024)

Synthesis and Characterization of Monomeric Triarylbismuthine Oxide.

The synthesis and isolation of a bismuth-based analogue of the venerable triphenylphosphine oxide (Ph3PO) has remained a chimera to synthetic chemists for many years, due to its predicted high reactivity and instability. Through the hydrolysis of a cationic fluorotriarylbismuthonium(V) salt, we report here the isolation of unique hydroxytriarylbismuth(V) complexes, which served as precursor for the formation of the elusive monomeric triarylbismuthine oxide Dipp3Bi═O. Combined spectroscopic, crystallographic and computational studies provided insight into the bonding situation of the first monomeric triorganobismuth oxide complex. The Dipp3Bi═O and Mes3BiO·LiBArF complex exhibits O-atom transfer reactivity, an uncommon reactivity feature for Ar3Pn=O.

Synthesis and Characterization of Monomeric Triarylbismuthine Oxide

The synthesis and isolation of a bismuth‐based analogue of the venerable triphenylphosphine oxide (Ph3PO) has remained a chimera to synthetic chemists for many years, due to its predicted high reactivity and instability. Through the hydrolysis of a cationic fluorotriarylbismuthonium(V) salt, we report here the isolation of unique hydroxytriarylbismuth(V) complexes, which served as precursor for the formation of the elusive monomeric triarylbismuthine oxide Dipp3Bi═O. Combined spectroscopic, crystallographic and computational studies provided insight into the bonding situation of the first monomeric triorganobismuth oxide complex. The Dipp3Bi═O and Mes3BiO·LiBArF complex exhibits O‐atom transfer reactivity, an uncommon reactivity feature for Ar3Pn=O.

Full Picture of Energy Transfer in a Trivalent Europium Complex with Bidentate β-Diketonate Ligand.

Trivalent europium (Eu(III)) complexes emit narrow-band luminescence as a result of energy transfer following the photoexcitation of antenna ligands. Bidentate β-diketonates are typically used as antenna ligands; however, their entire energy transfer mechanism to Eu(III) remains unknown. We used time-resolved photoluminescence spectroscopy and femtosecond transient absorption spectroscopy to map the complete intramolecular energy transfer process in the [Eu(hfa)3(TPPO)2] (hfa = hexafluoroacetylacetonate, TPPO = triphenylphosphine oxide) complex; hfa is a β-diketonate antenna ligand. Our analysis provides a "full picture" of energy transfer, tracing each step from initial photoexcitation to final relaxation: intersystem crossing in the ligands, energy transfer from the ligands to the metal center, and multiple internal conversion of Eu(III). We demonstrated that the direct bonds of the bidentate ligands enabled a quick and near-unity-efficiency energy transfer from the triplet state of the ligand to the 5D2 state of Eu(III). We also revealed that the loss of the ligand-centered intersystem crossing process reduces the overall sensitization efficiency. Our findings provide a foundation for the rational design of advanced luminescent materials, paving the way for advances in lanthanide-based luminescence research.

Precision across temperatures: Eu/Tb luminescent thermometer with exceptionally high and stable sensitivity from 180 to 320 K

Luminescence thermometry, leveraging the temperature-dependent luminescent properties of coordination compounds, offers precise and remote temperature measurement. However, many existing luminescent thermometers exhibit a narrow peak in temperature sensitivity, restricting their effective operating range. In this study, we synthesized new complexes [LnL2(NO3)(TPPO)2], where Ln = Eu (1), Tb (2), Gd (3), Tb0.94Eu0.06 (4), (HL - 4,4,4-trifluoro-1-(furan-2-yl) butan-1,3-dione, TPPO - triphenylphosphine oxide, which demonstrate an exceptionally wide and stable range of maximum temperature sensitivity of 3 %×K−1, spanning from 180 to 320 K. Furthermore, the temperature uncertainty remained low and stable across the same temperature region, ensuring reliable measurements. An unusual behavior was observed in the ion-to-ion energy transfer process rate constant, which exhibited an additional peak between 120 and 180 K. This phenomenon warrants further investigation to fully understand the underlying mechanisms. The obtained results allow for creation of new highly efficient luminescent thermometers tailored for specific complex applications, including cryobiology and microfluidics.

Triphenylphosphine Oxide: A Versatile Covalent Functionality for Carbon Nanotubes.

Broadening the scope of functionalities that can be covalently bound to single-walled carbon nanotubes (SWCNTs) is crucial for enhancing the versatility of this promising nanomaterial class in applied settings. Here we report the covalent linkage of triphenylphosphine oxide [Ph3P(O)] to SWCNTs, a hitherto overlooked surface functionality. We detail the synthesis and structural characterization of a new family of phosphine oxide-functionalized diaryliodonium salts that can facilitate direct Ph3P(O) transfer and afford novel SWCNTs with tunable Ph3P(O) content (SWCNT-P). The molecularly-distributed and robust nature of the covalent Ph3P(O) attachment in SWCNT-P was supported by a combination of characterization methods including Raman, infrared, UV/Vis-NIR and X-ray photoelectron spectroscopies coupled with thermogravimetric analysis. Electron microscopy further revealed the effectiveness of the Ph3P(O) moiety for de-bundling SWCNTs to yield SWCNT-P with superior dispersibility and processability. Finally, electrochemical studies established that SWCNT-P is sensitive to the presence of Li+, Na+ and K+ wherein the Gutmann-Beckett Lewis acidity parameters of the ions were quantitatively transduced by Ph3P(O) to electrochemical responses. This work hence presents a synthetic, structural, spectroscopic and electrochemical foundation for a new phosphorus-enriched responsive nanomaterial platform featuring the Ph3P(O) functionality.

Triphenylphosphine Oxide: A Versatile Covalent Functionality for Carbon Nanotubes

AbstractBroadening the scope of functionalities that can be covalently bound to single‐walled carbon nanotubes (SWCNTs) is crucial for enhancing the versatility of this promising nanomaterial class in applied settings. Here we report the covalent linkage of triphenylphosphine oxide [Ph3P(O)] to SWCNTs, a hitherto overlooked surface functionality. We detail the synthesis and structural characterization of a new family of phosphine oxide‐functionalized diaryliodonium salts that can facilitate direct Ph3P(O) transfer and afford novel SWCNTs with tunable Ph3P(O) content (SWCNT‐P). The molecularly‐distributed and robust nature of the covalent Ph3P(O) attachment in SWCNT‐P was supported by a combination of characterization methods including Raman, infrared, UV/Vis‐NIR and X‐ray photoelectron spectroscopies coupled with thermogravimetric analysis. Electron microscopy further revealed the effectiveness of the Ph3P(O) moiety for de‐bundling SWCNTs to yield SWCNT‐P with superior dispersibility and processability. Finally, electrochemical studies established that SWCNT‐P is sensitive to the presence of Li+, Na+ and K+ wherein the Gutmann‐Beckett Lewis acidity parameters of the ions were quantitatively transduced by Ph3P(O) to electrochemical responses. This work hence presents a synthetic, structural, spectroscopic and electrochemical foundation for a new phosphorus‐enriched responsive nanomaterial platform featuring the Ph3P(O) functionality.

Spectroscopic characterization of black N- and P-doped zeolite templated carbons

The incorporation of heteroatoms (X) into the zeolite-templated carbon (ZTC) structure is a widely used technique to tailor its properties for specific applications such as gas adsorption, methane and hydrogen storage, and catalysis. However, the literature lacks sufficient data on Fourier-transform infrared spectroscopy (FTIR) analysis of ZTCs due to the challenge in obtaining high-quality FTIR spectra required for accurate assignment of the C–X bands, primarily caused by the black mass effect. In this work we prepared nitrogen (N) and phosphorus (P) doped ZTC samples using FAU type zeolite as a template and furfuryl alcohol as a carbon precursor. The Raman results confirmed the presence of medium-sized aromatic structures and also showed that doping these structures with N and P leads to some defects, although the overall conformation remains structurally intact. The FTIR spectra of the ZTC materials were obtained by controlling the preparation procedure and humidity, enabling clear analysis of the black samples. A Density Functional Theory (DFT) model based on the dimeric buckybowl structure was developed and complemented by experimental results obtained from X-ray photoelectron spectroscopy (XPS), nuclear magnetic resonance (NMR), and FTIR. The proposed DFT model was then used for deconvolution and precise band assignment of the experimental FTIR spectra. The FTIR deconvolution study also supported the incorporation of N and P into the ZTC as well as the presence of primarily two types of nitrogen species, amide (primary and secondary) and pyridine-like, while P was mainly incorporated as triphenylphosphine oxide and phosphonic acid.

Fabrication of POE/POE‐g‐PHEMA/EuFT light conversion films for photovoltaic modules

AbstractIn this paper, the rare earth europium complex Eu(FTFA)3TPPO2 (EuFT) was synthesized by using europium as the central ion, 4‐trifluoro‐1‐(2‐furanyl)‐1,3‐butanedione (FTFA) as the first ligand, and triphenylphosphine oxide (TPPO) as the second ligand. The structure was characterized by Fourier transform infrared spectroscopy (FTIR), and the photoluminescence process was investigated by UV and fluorescence spectra. The luminescent film was prepared by adding EuFT and the compatibilizer POE‐g‐PHEMA into the POE matrix, which can convert the UV light to the red light, and improve the photovoltaic conversion efficiency while reducing the effect of UV aging on the cell. Experimental results show that the complex can absorb UV light (200–400 nm) and emit red light (612 nm), the luminescent film also maintains good luminescence performance. The peel strength of POE/POE‐g‐PHEMA/EuFT film achieves 23.9 N cm−1，while that of POE film is 12.8 N cm−1. The silicon cell prepared by POE/POE‐g‐PHEMA/EuFT film also showed higher EQE in UV region, and its current density–voltage (J–V) curve revealed that Jsc increased from 33.05 to 34.25 mA/cm2, the conversion efficiency increased from 12.99% to 13.39%, and the relative efficiency increased by 3.08%. The rare earth europium complex effectively improved the photoelectric conversion efficiency of solar cells.

Investigation of the Optimal Phosphine for Improved Electrochemical Peptide Synthesis

Peptides have been expected to be medicines with higher specificity and fewer side effects than conventional medicines. However, a longstanding problem that the huge amount of waste is produced in synthetic process is not resolved. One of the causes is use of coupling reagents. Although they facilitate efficient peptide bond formation, byproducts lead to accumulation of waste. To address the issue, we developed electrochemical peptide synthesis using triphenylphosphine (Ph3P) as a coupling reagent. Anodic oxidation of Ph3P generates radical cation to activate carboxylic acids and promote peptide bond formation, producing triphenylphosphine oxide (Ph3PO). Since the reduction of Ph3PO to Ph3P is achieved in various ways, Ph3P have a potential to be a recyclable coupling reagent, which would be one of the solutions. Actually, we succeeded in development of an electrochemical peptide synthesis applicable to all of canonical amino acids and recovering method of Ph3PO. Nevertheless, we found that this method is difficult to use for highly sterically hindered amino acids. To improve the reaction efficiency, we examined various phosphine derivatives instead of Ph3P. We will present our recent improvement of the electrochemical peptide synthesis and nature of phosphine radical cations in detail.

Anthracene derivatives with electron-transport units for non-doped blue fluorescent organic light-emitting diodes

Blue organic light-emitting diodes with non-doped emissive layer (EML) structures have been garnered increasing interest due to their convenience of manufacturing process. For this purpose, we designed and synthesized two novel anthracene derivatives, PO2PhAnTz and PO2PhAnBI. Both derivatives exhibited bright blue electroluminescence emission and a relatively low operating voltage with a simple bilayer device structure. The PO2PhAnBI with triphenyl-phosphine oxide moiety as host, anthracene core as dopant and benzimidazole as electron transport group, realized a balanced bipolar transport and attained a maximum external quantum efficiency of 5.74 %. The findings shed light on the molecule design role toward high-efficiency non-doped blue OLEDs.

MgCl2 and Wet Milling Efficiently Removes Triphenylphosphine Oxide

MgCl2 and Wet Milling Efficiently Removes Triphenylphosphine Oxide

One-Pot Synthesis of 4-Chloroquinolines via Bis(trichloromethyl) Carbonate and Triphenylphosphine Oxide-Mediated Cascade Reactions of N-Aryl Enaminones.

A novel method for synthesizing substituted 4-chloroquinolines has been devised, utilizing a cascade reaction of N-aryl enaminones promoted by bis(trichloromethyl) carbonate (BTC) and triphenylphosphine oxide (TPPO). This approach features accessible starting materials, a broad substrate range, extensive functional group compatibility, gentle reaction conditions, and straightforward operation. Its versatility is evidenced by its facile scalability and suitability for late-stage derivatization. A plausible mechanism involving α-carbonylation, 6π-azaelectrocyclization, and dehydroxychlorination sequence is proposed.

Spatial heterogeneity, sediment-water exchange, and diffusion mechanisms of organophosphate esters from river to coastal aquatic system in a typical economic circle of northern China

Organophosphate esters (OPEs) have proven to be pervasive in aquatic environments globally. However, understanding their partitioning behavior and mechanisms at the sediment-water interface remains limited. This study elucidated the spatial heterogeneity, interfacial exchange, and diffusion mechanisms of 14 OPEs (∑14OPEs) from river to coastal aquatic system. The transport tendencies of OPEs at the sediment-water interface were quantitatively assessed using fugacity methods. The total ∑14OPEs concentrations in water and sediments ranged from 154 ng/L to 528 ng/L and 2.41 ng/g dry weight (dw) to 230 ng/g dw, respectively. This result indicated a descending spatial tendency with moderate variability. OPE distribution was primarily influenced by temperature, pH, and dissolved oxygen levels. As the carbon atom number increased, alkyl and chlorinated OPEs transitioned from diffusion towards the aqueous phase to equilibrium. In contrast, aryl OPEs and triphenylphosphine oxide, which had equivalent carbon atom counts, maintained equilibrium throughout. Diffusion trends of individual OPE congener at the sediment-water interface varied at the same total organic carbon contents (foc). As the foc increased, the fugacity fraction values for all OPE homologs showed a declining trend. The distinct molecular structure of each OPE monomer might lead to unique diffusive behaviors at the sediment-water interface. Higher soot carbon content had a more pronounced effect on the distribution patterns of OPEs. The sediment-water distribution of OPEs was primarily influenced by total organic carbon, sediment particle size, dry density, and moisture content. OPEs displayed the highest sensitivity to fluctuations in ammonium and dissolved organic carbon. This study holds significant scientific and theoretical implications for elucidating the interfacial transport and driving forces of OPEs and comprehending their fate and endogenous release in aquatic ecosystems.

Improving the triphenylphosphine/triphenylphosphine oxide (TPP/TPPO)‐based method for the absolute and accurate quantification by FTIR‐ATR of hydroperoxides in oils or lipid extracts

AbstractResearch on natural sources of polyunsaturated fatty acids (PUFAs) for both food and nutraceutical prospects has significantly grown in recent years. Some plant oils and lipid extracts contain carotenoids, xanthophylls, sterols, and/or phenolic compounds that can provoke a lipid hydroperoxides (LOOHs) overestimation when quantifying them using nonselective colorimetric assays. Herein, we have optimized a mid‐infrared method using Fourier‐transform infrared spectroscopy coupled with attenuated total reflectance (ATR) to quantify LOOHs in oils or lipid extracts. This method is based on the conversion of triphenylphosphine (TPP) to triphenylphosphine oxide (TPPO) in the presence of hydroperoxides, with a direct assessment of TPPO levels following the formation of an oil film on the ATR crystal's surface, allowing for a low detection limit of 0.5 mmol of LOOH kg−1. The concentration of oil and TPP, as well as the reaction time, were optimized. It was demonstrated that the presence of pigments, unsaponifiable compounds, phenolics, and/or PUFAs on oils, do not disrupt the analysis. Furthermore, the stoichiometry of the TPP/LOOH reaction was examined, confirming the reliability of the method in detecting various forms of hydroperoxides. An accelerated oxidation study was carried out and the hydroperoxide contents measured using TPP/TPPO were found to be comparable to those obtained using the ferric thiocyanate method. Our method offers a fast, simple, robust, and sensitive approach to accurately quantify hydroperoxides, regardless of the chemical composition of oil or lipid extracts.Practical Application: The hydroperoxide assay method outlined in this study allows for the rapid and straightforward detection of hydroperoxides in pure oil matrices. The method's elevated sensitivity facilitates the early identification of oxidation indicators in oils, especially those with significant carotenoid or xanthophyll contents since these compounds may affect the results when using methods based on colorimetric quantification of hydroperoxides. This accurate, precise, and reproducible approach requires only small quantities of test samples and chemical products, making it well suited to routine application in laboratories and industrial environments.

Community-level risk assessments on organophosphate esters in the sediments from the Bohai Sea of China based on multimodal species sensitivity distributions coupled with the equilibrium partitioning method

Organophosphate esters (OPEs), increasingly used as alternatives to brominated flame retardants, are ubiquitous in the global aquatic environment. Despite their potential toxicological impact on ecosystems, community-level risk assessments for OPEs in sediments remain scarce. This study investigated OPE occurrences and composition characteristics in the Bohai Sea's sediments and appraised both individual and joint ecological risks posed by characteristic OPE homologs using ten commonly used species sensitivity distribution (SSD) models, integrating acute-to-chronic conversion and phase equilibrium partitioning. OPEs were detected across all sediment samples, with total concentrations ranging from 0.213 ng/g dry weight (dw) to 91.1 ng/g dw. The predominant congeners included tri-n-butyl phosphate (TnBP), triisobutyl phosphate (TiBP), tri(2-ethylhexyl) phosphate, tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCPP), tris(1, 3-dichloro-2-propyl) phosphate (TDCIPP), and triphenylphosphine oxide. Best-fit SSD models varied among TnBP, TiBP, TCEP, TCPP, and TDCIPP, demonstrating Sigmoid, Burr III, Sigmoid, Burr III, and Burr III, respectively. The same parametric model demonstrated variability in the fitting process for different OPE congeners, which also happened to the fitting results of ten parametric models for the same specific characteristic congener, underscoring the necessity of employing multiple models for precise community-level risk assessments. Hazard concentrations for a 5% cumulative probability were 0.116 mg/L, 2.88 mg/L, 1.30 mg/L, 1.44 mg/L, and 1.85 mg/L for each respective congener. The resulting risk quotients (RQ) and overall hazard index (HI) were selected as criteria to assess the individual and joint ecological risks of OPEs in sediments from the Bohai Sea, respectively. RQ and HI were both below 0.1, indicating a low risk to the local ecosystems. Multi-model SSD analysis could provide refined data for community-level risk evaluation, offering valuable insights for the development of evidence-based environmental standards and pollution control strategies.

Degradation of organophosphate esters by UV/persulfate: Kinetic, mechanistic and toxicity evaluation

With the ban of brominated flame retardants, organophosphate esters (OPEs) have been widely used. The ultraviolet combined sodium persulfate (UV/PS) process is a promising advanced oxidation process (AOPs), which effectively removes organic micropollutants by generating various reactive substances such as hydroxyl radical (•OH) and sulfate radical (SO• 4−). The degradation kinetics, influencing factors, degradation path, and toxicity of three organic phosphates, trimethyl phosphate (TMP), tris (2-chloroethyl) phosphate (TCEP) and triphenyl phosphine oxide (TPPO) were studied. The results showed that UV/PS could degrade OPEs efficiently, and 254 nm UV light was more conducive to the degradation of OPEs than 365 nm UV light, and the degradation of OPEs accelerated with the increase of PS concentration. Under acidic and neutral conditions, UV/PS was more conducive to the degradation of OPEs, and the concentration of NOM was inversely proportional to the degradation rate of OPEs, Cl− and SO42− had almost no effect on the degradation of OPEs, while HCO3− has an inhibitory effect on the degradation of OPEs. UV/PS also has a good effect on the degradation of OPEs in actual water. •OH and SO• 4−, as the main reactive radicals, participate in the degradation of OPEs. Hydroxylation, debenzene ring, demethylation, and ring opening reactions are the main reactions occurring in the process of OPEs degradation. The theoretical toxicity value of most intermediates is lower than that of the initial OPEs. This study reveals the transformation of OPEs in the UV/PS system and provides a new idea for wastewater treatment of OPEs.

Migration characteristics and risk assessment of chemical hazardous substances in infant teether toys

Teether is a special toy used for infants oral contact. In this paper, a residual and migration detection method was developed using gas chromatography–tandem mass spectrometry for 20 screened hazardous substances in teethers. Fifteen substances were detected in 59 samples, with residual amounts and detection rates ranging from 0.01 mg⋅kg−1 to 106.15 mg⋅kg−1 and from 3.39 % to 84.7 % respectively. Then, 12 substances were detected in simulated saliva at migration levels ranging from 0.0143 mg⋅kg−1 to 20.03 mg⋅kg−1, with detection rates ranging from 1.69 % to 76.3 %. Statistically, the average migration rate of each substance ranged from 8.18 % to 53.28 % depending on the properties of the substance and the sample. The exposure risk of infants to teethers was evaluated separately for two age groups. The hazard quotient (HQ) and hazard index (HI) values for the analytes were higher in the 3–12-month age group than in the 12–24-month age group. The HQ values of triphenylphosphine oxide, benzocaine, and N-methylformanilide were relatively high, with averages of 1.2 × 10−2, 2.5 × 10−3, and 1.6 × 10−3, respectively, and the max HI of the 12 substances was 0.04. The HI and HQ values of the analytes were all below 1, indicating that the non-carcinogenic risks of analytes in teethers are at an acceptable level.