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Integration of lead‐halide perovskite quantum dots (PQDs) into full‐color microarrays presents numerous advantages for full‐color micro‐LED displays. There is an urgent requirement for a new design approach that simplifies the creation of durable PQD/polymer composites to produce stable PQD microarrays. Here, mono‐2‐(methacryloyloxy)ethyl succinate (MMeS) is utilized as a functional ligand to synthesize green MMeS‐modified CsPbBr3 PQDs (M‐CPB PQDs). The subsequent photopolymerization of M‐CPB PQDs with 1,6‐hexanediol diacrylate (HDDA) forms a CsPbBr3 PQD/polymer composite. This composite exhibits a solid‐state photoluminescence quantum yield of 73.1%, and the photoluminescence intensity retains 72% of its original value after 17 days of continuous immersion in water. Stable green PQD/polymer microarrays can be printed using an ink containing M‐CPB PQDs, HDDA, diphenyl (2,4,6‐trimethylbenzoyl) phosphine oxide, and n‐dodecane via electrohydrodynamic jet printing and in situ polymerization under UV light irradiation. Full‐color patterns can also be generated with MMeS‐modified red, green, and blue PQDs. These findings highlight the critical role of functionalizing the surface ligands of PQDs to improve their processability, thereby facilitating the development of stable PQD/polymer microarrays. [ABSTRACT FROM AUTHOR]

Despite the appeal of organic redox systems as next-generation energy-storage media, achieving high cell voltages with electrolytes based on main-group elements typically comes at the cost of reduced long-term stabilities. In this Synpacts article, we summarize our recent finding that the introduction of phosphine oxide functionalities can unlock the ability of terthiophenes to serve as robust two-electron acceptors at extreme potentials. These investigations uncovered a fundamentally new class of multielectron redox systems, capable of expanding the cell potential range achievable with organic electrolytes without compromising stability. [ABSTRACT FROM AUTHOR]

Positively charged phosphorus‐containing heterocycles are characteristic core skeletons for functional molecules. While various phosphonium‐containing five‐ or six‐membered‐ring compounds have been reported, the seven‐membered‐ring phosphepinium have not been fully studied yet. In this study, dithieno[3,2‐b; 2′,3′‐f]phosphepinium ions containing electron‐donating aminophenyl groups were synthesized. An X‐ray crystallographic analysis of the resulting donor–acceptor–donor dyes revealed a bent conformation of the central seven‐membered ring. These compounds exhibit fluorescence in the near‐infrared region with a bathochromic shift of ca. 70 nm compared to a phosphepine oxide congener and a large Stokes shift. High fluorescence quantum yields were obtained even in polar solvents due to the suppression of the nonradiative decay process. A theoretical study revealed that the phosphepinium skeleton is highly electron‐accepting owing to the orbital interaction between a px orbital of the phosphonium moiety and a π* orbital of the 1,3,5‐hexatriene moiety. Due to the lower‐lying px orbital in the phosphonium moiety compared to that of the phosphine oxide and the bent conformation of the seven‐membered ring, the phosphepinium ring permits effective px–π* conjugation. A large structural relaxation with a contribution of a quinoidal resonance structure is suggested in the excited state, which should be responsible for the bright emission with a large Stokes shift. [ABSTRACT FROM AUTHOR]

Phosphotungstic acid with a Keggin structure as an efficient, simple and green catalyst for the phosphinylation of secondary propargyl alcohols with phosphine oxides to afford γ-ketophosphine oxides with up to 88% isolated yield was developed using dimethyl carbonate as a green solvent. Diaryl- or alkylaryl-substituted propargyl alcohols, and diaryl or arylalkylphosphine oxides could tolerate the system, which reduced the catalyst dosage, and avoided the use of multi-components and toxic solvents. More interestingly, phosphotungstic acid exhibited the best activity when 0.58 moles of water were added per mole of HPWA, elevating the yield from 55% to 85%. An 18O labelled product was afforded using trace H218O instead of H2O, indicating the participation of water in the reaction. Besides, our work underscores the importance and effect of a small amount of water, acting to promote the transformation of secondary propargyl alcohols into enones, which should be the real intermediates of the reaction. A mechanism involving a carbocation, Meyer–Schuster rearrangement and Michael addition of enones was proposed. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) composed of a beta-diketone and phosphine oxides featuring different alkyl chain lengths were prepared and then employed as liquid-liquid extraction and dissolution media for the separation of iron, cobalt, neodymium, and dysprosium. In the dissolution the more sterically hindered DESs exhibited enhanced selectivity to neodymium, which was poorly separated using liquid-liquid extraction. The dissolution selectivity in less sterically hindered DESs could be controlled by the addition of organic acids with different alkyl chain lengths. [ABSTRACT FROM AUTHOR]

A visible‐light‐promoted chemodivergent phosphorylation‐peroxidation and oxyphosphorylation of alkenes with phosphine oxides and HOOtBu was realized under transition‐metal‐free conditions. Using the commercially available Eosin Y as a SET‐photocatalyst, the β‐peroxy‐phosphine oxides were selectively obtained with a catalytic amount of base, while the addition of acid led to the exclusive formation of β‐keto‐phosphine oxides control experiments showed that Eosin Y could also act as a HAT‐catalyst to induce the O−O bond cleavage of peroxides under acidic conditions. [ABSTRACT FROM AUTHOR]

Efficient organic blue materials are essential to develop highly efficient organic light-emitting diodes. However, there is a challenge to commercialize efficient blue compounds due to the fundamentally wide band gap and the lack of pure blue emitters. In this study, the new anthracene-based fluorescent emitter, (4-(10-(4-(9H-carbazol-9-yl)-2-methylphenyl)anthracen-9-yl)-3-methylphenyl)diphenylphosphine oxide (CZm-AN-mPO) was designed and synthesized. The thermal, photophysical and electrochemical properties of the CZm-AN-mPO were systematically investigated. The CZm-AN-mPO exhibits a deep-blue emission at 425 nm and AIE property with a relatively narrow full-width at half maximum of 34 nm. The CZm-AN-mPO based non-doped devices show pure blue emission. The optimized OLEDs indicated maximum external efficiencies of 4.3% and 4.2% at emission layer thickness of 20 nm and 40 nm, respectively. [ABSTRACT FROM AUTHOR]

A photooxidation approach to the conversion of phosphines into the corresponding phosphine oxides is reported. By taking advantage of O2 in the air as an oxidant and oxygen source, phosphine oxides were obtained efficiently in moderate to excellent yields. A four-coordinated organoboron compound was used as the photocatalyst to activate O2 to its singlet state. This photooxidation method features mild reaction conditions, broad functional-group tolerance, and a wide substrate scope. [ABSTRACT FROM AUTHOR]

New phosphorus-containing isatin-3-hydrazones were synthesized by the condensation reaction of 5-substituted isatins with 2-chloroethyl [4-(dimethylamino)phenyl](2-hydrazinyl-2-oxoethyl)phosphinate (KAPAKh). The resulting compounds were shown to have high antitumor activity against duodenal adenocarcinoma (HuTu80) and cervical epithelioid carcinoma (M-HeLa) cell lines with low toxicity towards erythrocytes and normal human liver cells. [ABSTRACT FROM AUTHOR]

An approach for the preparation and stabilization of primary phosphine oxides is presented complementing previous methods of in situ generation. Specifically, RP(O)H2 where R=benzyl (Bn), cyclohexyl (Cy), 2‐naphthyl (2‐Naph), phenyl (Ph), tert‐butyl (t‐Bu) was prepared by controlled oxidation of the corresponding primary phosphine in presence of ferrocene as stabilizing reagent. The primary phosphine oxides were characterized using NMR and MS and studied in twofold hydrophosphorylation of diketones. The domino‐phospha‐aldol reaction catalysed with 5 mol% of sodium methoxide yielded five‐, six‐ and seven‐membered heterocyclic tertiary phosphine oxides with a high degree of stereoselectivity, as confirmed by single X‐ray diffraction. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Solvent- and catalyst-free reaction of 3-R-1H-phospholane oxides with aldehydes at 20–22 °C for 30 min gave the mixtures of four diastereomers of the corresponding 3-substituted 1-hydroxymethyl-1H-phospholane oxides in 85–98% yields. [ABSTRACT FROM AUTHOR]

Isostructural binuclear complexes [Ln2L2(hfac)6] (Ln = Eu, Tb; hfac– = hexafluoroacetylacetonate ion) are synthesized by the interaction of [Ln(hfac)3(H2O)2] with 3,6-bis(diphenylphosphinyl)pyridazine (L). According to the single-crystal XRD data, two Ln(hfac)3 moieties in the complexes are connected by two O,O´-bidentate-bridging ligands L, and the coordination polyhedron Ln@O8 has the geometry of a triangular dodecahedron. The Eu3+ and Tb3+ complexes exhibit characteristic lanthanide-centered photoluminescence in the solid state at 297 K with luminescence quantum yields of 31% and 2% and excited state lifetimes of 707 and 30 μs, respectively, thus indicating that luminescence sensitization by the ligand environment is more effective for Eu3+ than for Tb3+. [ABSTRACT FROM AUTHOR]

Acyclic acylphosphine oxides have been extensively utilized in industrial applications as typical photoinitiators (PIs). In this study, we demonstrate the efficiency of their cyclic analogues, cyclo‐bis(acyl)phosphine oxides (CBAPOs), as efficient PIs. We present the isolation and X‐ray crystallographic characterization of CBAPOs. These compounds exhibit a long maximum absorption wavelength ranging between 415 and 420 nm, extending well into the near 500 nm region. Radical trapping experiments suggest that CBAPOs undergo homolytic P−C(O) bond α‐cleavage. Steady‐state photolysis conducted with LED light at 390 nm, monitored by UV‐Vis spectroscopy, confirms the gradual decay of CBAPOs over time. Additionally, all CBAPOs are capable of initiating radical polymerization under irradiation at 365 nm. Notably, one of the CBAPOs (4a) demonstrates comparable photoinitiating efficiency to one of commercially available bis(acyl)phosphine oxides (Irgacure 819). [ABSTRACT FROM AUTHOR]

This paper presents the efficient reduction of phosphinoylacetic acid esters and 3-phosphorylated coumarin to their corresponding phosphino-boranes using BH₃-THF complexes. Optimized conditions for the reduction of phosphinoylacetic acid esters resulted in high yields of phosphinoborates. The straightforwardness and efficiency of the process were demonstrated for diarylphosphinoylacetic acid ethyl esters, as well as P-stereogenic L-menthyl esters, where the simultaneous reduction of the strong P=O bond and the ester group was exclusively observed for the first time. The study also highlighted the significant influence of steric effects with bulky substituents, such as the menthol group or the 1-naphthyl substituent at phosphorus, on the reduction efficiency. However, the reduction of 3-phosphorylated coumarins produced an unexpected reaction product: a 2,3-dihydrobenzofuran derivative. The present findings provide valuable information on the direct reduction of phosphine oxides and related compounds, demonstrating the versatility of borane complexes in synthetic chemistry, and provide new perspectives for studying the problems of symmetry and asymmetry in the chemistry of such transformations. [ABSTRACT FROM AUTHOR]

Herein, we present a radical cascade addition cyclization sequence to access quinoline‐based benzophosphole oxides from ortho‐alkynylated aromatic phosphine oxides using various aryl isonitriles as radical acceptors and inexpensive tert‐butyl‐hydroperoxide (TBHP) as a terminal oxidant in the presence of a catalytic amount of silver acetate. Alternatively, the same cascade can be realized through a sustainable photochemical approach utilizing 1,2,3,5‐tetrakis(carbazol‐9‐yl)‐4,6‐dicyanobenzene (4CzIPN) as an organic photocatalyst at room temperature. The introduced modular approach shows broad functional group tolerance and offers straightforward access to complex P,N‐containing polyheterocyclic arenes. These novel π‐extended benzophosphole oxides exhibit interesting photophysical and electrochemical properties such as absorption in the visible region, emission and reversible reduction at low potentials, which makes them promising for potential materials science applications. The photophysical properties can further be tuned by the addition of external Lewis and Brønsted acids. [ABSTRACT FROM AUTHOR]

Carbon–phosphorus bond formation is of great importance in synthetic chemistry. A versatile strategy for the formation of carbon–phosphorus bonds involves the addition of phosphorus radicals to π-systems. However, the generation methods of phosphorus radicals are primarily restricted to homolytic cleavage of phosphorus–hydrogen bonds with excess peroxides or toxic metal salts as oxidants. Herein, we introduce a photoinduced palladium-catalyzed generation of phosphorus radicals using inexpensive and readily available Cl–phosphine oxides and Cl–phosphates as the phosphorus radical precursors. The key step for this strategy lies in the reductive activation of phosphorus–chloride bonds with the excited palladium complex under visible light irradiation. The involvement of phosphorus radicals has been evidenced by EPR spectroscopy and radical trapping experiments. Based on this strategy, both phosphinyl and phosphonyl groups could be regiospecifically incorporated into simple alkenes and heteroaromatic compounds via radical mediated carbon–phosphorus bond formation. Besides, carbon–phosphorus difunctionalization of alkenes was also achieved to afford phosphorylated oxindoles. [ABSTRACT FROM AUTHOR]

A copper‐catalyzed one‐pot three‐component aminophosphinoylation reaction of 1,4‐naphthoquinone with disubstituted phosphine oxides and arylamines has been developed. Various disubstituted phosphine oxides and arylamines with diverse structures and electronic properties can work smoothly with 1,4‐naphthoquinone, afforded a series of corresponding aminophosphinoylated 1,4‐naphthoquinones with up to 96 % isolated yield. The present method features easily available reagents, operational simplicity, broad substrate scope, high atom and step economy. The potential practicality of this protocol was further demonstrated by gram‐scale synthesis. [ABSTRACT FROM AUTHOR]

A silver-catalyzed chemoselective cascade nucleophilic addition of a P-centered anion to isocyanides and cyclization reaction was developed for the efficient and practical synthesis of a wide range of 2-phosphinoyl indole and indol-3-ol derivatives. Unlike the well-documented synthesis of phosphorus-functionalized heterocycles via a P-centered radical, an anionic reactivity profile of phosphine oxides is most likely involved in this domino transformation. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis of a new P-chiral phospholene core-based ligand called LemPhos. The authors propose a method using a chiral diene to create diastereomers that are easier to separate, allowing for the production of P-chiral ligands. The ligands are synthesized and characterized, and their application as catalysts in asymmetric hydrogenation reactions is explored. The document also includes experimental procedures and spectroscopic data for the synthesized compounds. The research is dedicated to the memory of Stanisław Lem, a renowned science-fiction writer. [Extracted from the article]

A rigid pentadentate chelating ligand (H2L) has been utilized to synthesize a series of octacoordinate mononuclear complexes, [Dy(L)(Ph3PO)(OOCR)] (where R = C6H5 (1), C(CH3)3 (2), CF3 (3)) and a dinuclear complex, [Dy2(L)2(Ph3PO)2{(OOC)2C6H4}] (4) based on the highly anisotropic Dy(III) ion. All the complexes were structurally characterized by single-crystal X-ray diffraction studies. The complexes were formed by the coordination action of the dianionic pentadentate ligand [L]2−, one phosphine oxide, and carboxylate ligands. DC and AC magnetic measurements were performed on 1–4. Complexes 1–4 show SMM behaviour, under zero DC field for 1 and 4, and under 500 Oe and 1000 Oe DC fields for 2 and 3 respectively, with thermally activated, Raman, and Raman and quantum tunnelling dominant relaxation mechanisms for 1 and 2, 3 and 4, respectively. [ABSTRACT FROM AUTHOR]

Novel 1-phenyl(1-thiophen-2-yl)-4-(diphenylphosphoryl)butane-1,3-diones were synthesized by the Claisen-type condensation of 1-(diphenylphosphoryl)propan-2-one with ethyl phenyl(thiophene-2-yl)carboxylates. The tautomeric equilibrium of diketone moiety of phosphine oxides was investigated by 1H and 13C{1H} NMR spectroscopy. Two species out of five possible tautomers (diketo and mono-enol) were observed in the solution of 1-phenyl(1-thiophen-2-yl)-4-(diphenylphosphoryl)butane-1,3-diones. The major tautomer was the mono-enol form with content 80–90%. Furthermore, the double bond position at C3 atom was determined by 13C{1H} NMR spectroscopy. [ABSTRACT FROM AUTHOR]

This article discusses a study on a new method for a visible-light-induced three-component radical coupling. The researchers tested the reaction of selenocarbonates and selenocarbamates and found that increasing the stability of the acyl radical facilitated the reaction. They also explored the reaction under thermal and photochemical conditions and provided detailed experimental data. The research has potential applications in natural-products synthesis and provides insights into the mechanism of the reaction and its potential applications in organic synthesis. [Extracted from the article]

In general, the P-centered ring-opening of quaternary phosphirenium salts (QPrS) predominantly leads to hydrophosphorylated products, while the C-centered ring-opening is primarily confined to intramolecular nucleophilic reactions, resulting in the formation of phosphorus-containing cyclization products instead of difunctionalized products generated through intermolecular nucleophilic processes. Here, through the promotion of ring-opening of three-member rings by iodine anions and the quenching of electronegative carbon atoms by iodine cations, we successfully synthesize β-functionalized vinylphosphine oxides by the P-addition of QPrS intermediates generated in situ. Multiple β-iodo-substituted vinylphosphine oxides can be obtained with exceptional regio- and stereo-selectivity by reacting secondary phosphine oxides with unactivated alkynes. In addition, a variety of β-functionalized vinylphosphine oxides converted from C-I bonds, especially the rapid construction of benzo[b]phospholes oxides, demonstrates the significance of this strategy. P-centered ring-opening of quaternary phosphirenium salts (QPrS) predominantly leads to hydrophosphorylated products, while the C-centered ring-opening results mainly in the formation of phosphorus-containing cyclization products. Here the authors synthesize β-functionalized vinylphosphine oxides by the P addition of QPrS intermediates generated in situ. [ABSTRACT FROM AUTHOR]

Group 4 Lewis acids are well-known catalysts and precursors for (non-aqueous) sol–gel chemistry. Titanium, zirconium and hafnium halides, and alkoxy halides are precursors for the controlled synthesis of nanocrystals, often in the presence of Lewis base. Here, we investigate the interaction of Lewis bases with the tetrahalides (MX4, X = Cl, Br) and metal alkoxy halides (MXx(OR)4−x, x = 1–3, R = OiPr, OtBu). The tetrahalides yield the expected Lewis acid–base adducts MX4L2 (L = tetrahydrofuran or phosphine oxide). The mixed alkoxy halides react with Lewis bases in a more complex way. 31P NMR spectroscopy reveals that excess of phosphine oxide yields predominantly the complexation product, while a (sub)stoichiometric amount of phosphine oxide causes disproportionation of the MXx(OR)4−x species into MXx+1(OR)3−x and MXx−1(OR)5−x. The combination of complexation and disproportionation yields an atypical Job plot. In the case of zirconium isopropoxy chlorides, we fitted the concentration of all observed species and extracted thermodynamic descriptors from the Job plot. The complexation equilibrium constant decreases in the series: ZrCl3(OiPr) > ZrCl2(OiPr)2 ≫; ZrCl(OiPr)3, while the disproportionation equilibrium constant follows the opposite trend. Using calculations at the DFT level of theory, we show that disproportionation is driven by the more energetically favorable Lewis acid–base complex formed with the more acidic species. We also gain more insight into the isomerism of the complexes. The disproportionation reaction turns out to be a general phenomenon, for titanium, zirconium and hafnium, for chlorides and bromides, and for isopropoxides and tert-butoxides. [ABSTRACT FROM AUTHOR]

A series of bis‐cyclometalated chiral‐at‐metal iridium(III) complexes containing a coordinated secondary phosphine oxide (SPO) have been synthesized and evaluated as catalysts in the asymmetric transfer hydrogenation (ATH) of acetophenone. The catalytic results show that SPO ligands have a non‐innocent role in activating the catalytic process. Additionally, it has been observed that for the same chiral descriptor (Δ‐at‐Ir or Λ‐at‐Ir), the major enantiomer formed depends on the nature of the cyclometalating ligand. These enantiodivergent results contravene the general assumption that the chiral‐at‐metal core‘s chirality dictates the sense of the chiral induction. A combined analysis of the main structural features of the catalysts deduced from XRD structures and in situ NMR spectroscopy allowed us to propose a simplified catalytic cycle and a working hypothesis to explain the observed enantioselectivities. [ABSTRACT FROM AUTHOR]

The solid‐state synthesis of perovskite BiFeO3 has been a topic of interest for decades. Many studies have reported challenges in the synthesis of BiFeO3 from starting oxides of Bi2O3 and Fe2O3, mainly associated with the development of persistent secondary phases such as Bi25FeO39 (sillenite) and Bi2Fe4O9 (mullite). These secondary phases are thought to be a consequence of unreacted Fe‐rich and Bi‐rich regions, that is, incomplete interdiffusion. In the present work, in situ high‐temperature X‐ray diffraction is used to demonstrate that Bi2O3 first reacts with Fe2O3 to form sillenite Bi25FeO39, which then reacts with the remaining Fe2O3 to form BiFeO3. Therefore, the synthesis of perovskite BiFeO3 is shown to occur via a two‐step reaction sequence with Bi25FeO39 as an intermediate compound. Because Bi25FeO39 and the γ‐Bi2O3 phase are isostructural, it is difficult to discriminate them solely from X‐ray diffraction. Evidence is presented for the existence of the intermediate sillenite Bi25FeO39 using quenching experiments, comparisons between Bi2O3 behavior by itself and in the presence of Fe2O3, and crystal structure examination. With this new information, a proposed reaction pathway from the starting oxides to the product is presented. [ABSTRACT FROM AUTHOR]

The surface morphology of perovskite films significantly influences the performance of perovskite light-emitting diodes (PeLEDs). However, the thin perovskite thickness (~10 nm) results in low surface coverage on the substrate, limiting the improvement of photoelectric performance. Here, we propose a molecular additive strategy that employs pentafluorophenyl diphenylphosphinate (FDPP) molecules as additives. P=O and Pentafluorophenyl (5F) on FDPP can coordinate with Pb2+ to slow the crystallization process of perovskite and enhance surface coverage. Moreover, FDPP reduces the defect density of perovskite and enhances the crystalline quality. The maximum brightness, power efficiency (PE), and external quantum efficiency (EQE) of the optimal device reached 24,230 cd m−2, 82.73 lm W−1, and 21.06%, respectively. The device maintains an EQE of 19.79% at 1000 cd m−2 and the stability is further enhanced. This study further extends the applicability of P=O-based additives. [ABSTRACT FROM AUTHOR]

A series of E＝P(V)-imine phosphine–imine ligands (Dipp-N＝C(CH3)–(CH2)–P＝E(Ph2)) (Dipp = 2,6-diisopropylphenyl, E = O, S, Se) and corresponding dimethyl aluminum and indium complexes were prepared and characterized using multi-nuclear NMR spectroscopy and SC-XRD. Solution-state 1H and 31P NMR spectroscopy indicate a mixture of isomers in solution (C6D6, CDCl3, and CD3CN). Solid state structures of both the imine and (E)-enamine isomers of the oxygen-based ligand have been observed. These three ligands (L) were then deprotonated with M(CH3)3 (M = Al or In), with methane loss forming a 6-membered ring via bidentate chelation ((κ2-L)M(CH3)2). The indium/oxide complex also crystallized as a 12-membered ring. [ABSTRACT FROM AUTHOR]

Photosensitizer design of luminescent terbium (Tb(III)) complexes with narrow bandwidths is important for advancing luminescent materials. In this study, we report an effective photosensitizer model in a thermally populated lowest excited triplet (T1) state during Tb(III) emission. The Tb(III) complex comprises a Tb(III) ion (serving as an emission center), hexafluoroacetylacetonates (acting as photosensitizer ligands), and bulky cyclohexyl group-attached phosphine-oxide-type ligands (functioning as an oxygen barrier system). Emission properties including emission and excitation spectra, ligand-excited emission quantum yields, and emission lifetimes were evaluated in the absence and presence of oxygen. Coordination geometry structures were determined through analysing single-crystal structures. The electronic structure based on 4f-orbitals was estimated from radiative rate constants and quantum chemical calculations. The bulky phosphine oxide ligand not only provides an oxygen barrier system but also induces an electronic structural modulation based on 4f-orbitals, allowing for effective photosensitized Tb(III) emission in a thermally populated ligand T1 state in air. [ABSTRACT FROM AUTHOR]

Despite the significance of chiral allene skeletons in catalysis, organic synthesis and medicinal chemistry et al. there is a scarcity of reports on axially chiral allenyl phosphorus compounds. Here, we disclosed an efficient and straightforward cascade reaction between ethynyl ketones and phosphine oxides, resulting in a broad array of trisubstituted allenes incorporating a phosphorus moiety in high yields with excellent stereoselectivities facilitated by peptide‐mimic phosphonium salt (PPS) catalysis, Additionally, comprehensive series of mechanistic experiments have been conducted to elucidate that this cascade reaction proceeds via an asymmetric Pudovik addition reaction followed by a subsequent phospha‐Brook rearrangement that occurs concomitantly with kinetic resolution, representing a stereospecific rearrangement and protonation process facilitating central‐to‐axial chirality transfer in a cascade manner. We anticipate that our research will pave the way for a promising exploration of novel stereo‐induction pattern in the Pudovik addition/phospha‐Brook rearrangement cascade reaction. [ABSTRACT FROM AUTHOR]

Despite the simplicity and abundance of ethylene, its practical application presents significant hurdles due to its nature as a highly flammable gas. Herein, a strategic use of easily handled vinyl ether is reported as a latent ethylene surrogate achieved via a spin‐center shift (SCS) pathway, enabling the successful three‐component reaction that bridges heteroarenes and various coupling partners, including sulfinates, thiols, and phosphine oxides. Through a photoredox catalytic process, α‐oxy radicals are generated by combining various radicals with phenyl vinyl ether, which are subsequently added to N‐heteroarenes. Subsequently, the radical‐mediated SCS pathway serves as the driving force for C─O bond cleavage, effectively engaging the phenoxy group as a leaving group. In addition, by broadening the utility of the method, a valuable synthon is provided for efficient C─H vinylation of N‐heteroarenes following sulfonyl group elimination. This approach not only enriches the toolbox of synthetic methodology but also provides a more streamlined alternative, circumventing the challenges associated with direct ethylene gas usage. The versatility of the method, particularly evident in late‐stage functionalizations of medicinally relevant molecules and peptides, underscores its capability to produce invaluable three‐component compounds and vinylated N‐heteroarene derivatives. [ABSTRACT FROM AUTHOR]

This article provides an overview of photoredox-catalyzed C(sp2)–H bond functionalization reactions, which use low-energy photons to enable reactions under mild conditions. It discusses the contributions of researchers in advancing the field and explores the potential of using organic photocatalysts. The article focuses on the author's group's work in utilizing these reactions for C–H bond functionalizations, specifically in the context of enamides. The researchers explored various reactions, including the functionalization of enamide β-C(sp2)-H bonds, phosphorylation of alkenyl C(sp2)-H bonds, and bromination and alkylation of (hetero)arene C(sp2)-H bonds. These reactions have applications in the synthesis of natural products and pharmaceuticals, and further research is needed to develop new transformations and expand their applications. [Extracted from the article]

Epimers of the (1,10-phenanthroline-2,9-diyl)bis(ethyl(phenyl)phosphine oxide) (Et-Ph-BPPhen) ligand with two chiral centers (R,R/S,S and R,S) were synthesized. The configurational effects on the coordination ability and mechanism between these epimeric ligands and uranyl ions were thoroughly investigated. This work is helpful to reveal the effects of different conformations of epimeric ligands on their coordination properties. [ABSTRACT FROM AUTHOR]

Visible-light-induced C(sp²)--H phosphorylation of 2H-thiozoles/quinoxalines with H-phosphine oxides was achieved using an inorganic-ligand supported Mo oxide ([N(C4H9)4]2[Mo6O19]) as a hydrogen atom transfer (HAT) photocatalyst. The developed photo-driven C(sp²)--P bond formation protocol could furnish a wide range of products with excellent functional group tolerance in a water-based solvent at room temperature, without the addition of metals, bases, additives or external oxidants. A gram-scale reaction can occur in a low catalyst loading system. Moreover, the formulated photocatalyst showed excellent stability and reusability, and also exhibited satisfactory photo-reactivity under sunlight irradiation. The mechanistic investigations supported that the C(sp²)--P bond formation went through radical coupling or radical nucleophilic addition pathways. [ABSTRACT FROM AUTHOR]

In next generation semiconductors, metal halide perovskite materials would replace traditional light‐emitting materials since their exceptional photoelectronic characteristics. The future development of perovskite light‐emitting diodes have generated challenges such as abundant surface or interfacial defects and exciton quenching. To overcome these challenges, the light‐emitting layer is modified utilizing benzimidazole/phosphine oxide hybrid 1,3,5‐tris(1‐(4‐(diphenylphenylphosphoryl)phenyl)‐1H‐benzo[d]imidazol‐2‐yl)benzene (TPOB) and 1,3,5‐tris(diphenylphosphoryl)benzene (TPO) with high triple energy state. It is demonstrated by X‐ray photoelectron spectroscopy results that the oxygen atoms in the P = O functional group of TPOB and TPO provided lone electron pairs coordinate to the unsaturated Pb2+ in turn led to a decrease in the electron cloud density of Pb2+ and Br‐, which can suppress defects. Additionally, this technique improved the morphology of film, reduced surface roughness, and facilitated carrier transport, all of which are crucial for achieving high‐emission efficiency. As a result, the optimal devices has EQEs of 16.20 (TPOB) and 20.48% (TPO), respectively. Furthermore, the devices demonstrated excellent reproducibility. Excitingly, the champion EQE value for the optimal device is 22.64%. Simultaneously, it can increase the stability of the devices and the lifetimes are increased from 1231 s (Pristine) to 5421 (TPOB) and 5631 s (TPO). [ABSTRACT FROM AUTHOR]

Thiochalcones undergo cycloaddition reactions in THF solution at 60 °C with the synthetically unexplored 1-phenyl-4H-phosphinin-4-one 1-oxide in a highly regio- and stereoselective manner, yielding hitherto unknown bicyclic P,S-heterocycles containing fused thiopyran and phosphinine rings. The stereochemical structures of two of the obtained (4+2)-cycloadducts were unambiguously assigned by means of the X-ray single-crystal analysis. Based on these assignments, a concerted mechanism of the hetero-Diels–Alder reaction via the preferred endo approach of the heterodiene from the less hindered P=O side of the phosphininone molecule is postulated to explain the established rac-(4RS,8SR,9SR,10SR)-configured (4+2)-cycloadducts isolated as major products. [ABSTRACT FROM AUTHOR]

Tris(hydroxymethyl)phosphine oxide, (HOCH2)3PO (THPO), is recognized as an efficient flame-retardant polyol and a derivative of PH3 – an environment-friendly, halogen-free source for phosphorus compounds and polymers. Synthesis and industrial production of THPO are based on straightforward oxidation of tris(hydroxymethyl)phosphine, (HOCH2)3P (THP), or neutralized tetrakis(hydroxymethyl)phosphonium chloride (THPC), or sulfate (THPS), by air/O2 or H2O2. In alkaline aqueous media, THP is oxidized by water with liberation of H2. As an alcohol, THPO readily reacts with isocyanates, epoxides, aziridines, and carboxylic acid derivatives, and is widely used as crosslinker or chain-extender to produce flame-retardant polyurethanes, polyethers, polyesters, and composite materials. Similarly, with compounds containing E–Cl bonds (E = P, Si, and S), THPO forms a variety of flame-retardant P/E-compounds or polymers. Condensation of THPO with phenols proceeds via cleavage of a P–C bond of THPO and liberation of CH2O that leads to flame-retardant THPO-phenol resins. With functionalized alkyl halides, THPO forms tris(alkoxymethyl)phosphine oxide monomers containing, for example, pendant allyl, propargyl, or silane groups. Halogenation of THPO leads to tris(chloromethyl)phosphine oxide, (ClCH2)3PO, or tris(bromomethyl)phosphine oxide, (BrCH2)3PO, useful for syntheses of multifunctional organophosphorus compounds, for example, tris(aminomethyl)phosphine oxide, (NH2CH2)3PO, and phosphorus-containing podands. Similar to THPO, tris(hydroxymethyl)phosphine sulfide, (HOCH2)3PS, is used in preparation of flame-retardant components for polymers, and, in synthesis of asymmetric phosphorus compounds. [ABSTRACT FROM AUTHOR]

A photocatalytic radical carbophosphorylation/cyclization of N-homoallyl aldehyde hydrazones with phosphine oxides was developed under metal-free conditions, achieving phosphorylated tetrahydropyridazines in yields up to 95%. Phosphorylated dihydropyrazoles were also constructed, by reacting N-allyl aldehyde hydrazones with phosphine oxides under the same conditions. [ABSTRACT FROM AUTHOR]

The present review shows metal‐catalyzed oxidative C(sp3)‐H/C(sp2)‐H bond functionalization of 1,4‐benzoxazinones by utilizing various substrates such as indoles, phosphites or phosphine oxides, malonate esters, and resorcinol, which lead to the formation of new C−C or C−P bonds. The metal catalysts used for these couplings include Fe, Cu, Ag, and Ru. This follows a strategy involving either the one‐electron oxidation process (OEO), ball milling technique, or photocatalytic process. The synthesized products in this method show usefulness in natural products, materials, agriculture, and medicinal chemistry. [ABSTRACT FROM AUTHOR]

A safe and efficient method for the in‐situ preparation of (diazomethyl)dimethylphosphine oxide – a hereto unexplored diazoalkane reagent – is developed. The method is based on the diazotization of the corresponding P(O)Me2‐substituted amine (readily available in multigram quantities) in non‐aqueous media. The protocol provides the target product as ca. 1.5 M CHCl3 solution which is stable at −18 °C. The utility of the synthesized diazoalkane is illustrated by its [3+2] cycloaddition with electron‐poor alkynes and alkenes providing the corresponding P(O)Me2‐substituted pyrazoles and pyrazolines with moderate to good efficiency. In this view, the title compound represents and an important extension of medicinally relevant phosphine oxide reagents. [ABSTRACT FROM AUTHOR]

Self-assembly reaction of Ln3+ and Ag+ ions with a multidentate N,O-donor ligand has been successfully applied to isolate the first examples of 4f-4d heterometallic coordination compounds based on a phosphine oxide linker. In particular, a series of one-dimension coordination polymers [LnAg(Py3PO)2(NO3)4]n (Ln = Sm, Eu, Tb, Dy) have been synthesized employing tris(2-pyridyl)phosphine oxide (Py3PO) as a bridging ligand. Coordination polymers exhibit good photostability and high thermal stability above 300 ℃. Their solid-state photoluminescence spectra represent a combination of emissions originating from the lanthanide f-f transitions and Ag+-involved charge transfer, resulting in the color-tunable luminescence depending on excitation light. [ABSTRACT FROM AUTHOR]

The article discusses the synthesis of P-chiral tertiary phosphine oxides through copper-catalyzed dynamic kinetic asymmetric C-P cross-coupling. P-stereogenic compounds are important in various fields, but their conventional synthesis methods have limitations. The use of secondary phosphine oxides (SPOs) as an alternative reagent has been explored, but challenges such as racemization and side reactions remain. The authors developed a copper catalyst and optimized reaction conditions to achieve highly enantioselective C-P coupling reactions, resulting in a wide range of P-stereogenic compounds with high yields and enantioselectivities. The resulting compounds can be further transformed into structurally diverse P-chiral scaffolds. The article also highlights the limitations and areas for future research in this field. [Extracted from the article]

Using a straightforward sequence of diphosphonylation and a Pd‐catalysed concerted‐metalation‐deprotonation (CMD), a synthetic strategy towards polyaromatic phosphorus containing heterocycles was developed. Herein, we report the synthesis and characterization of new azaphosphaphenalenes, using easily accessible palladium catalysts and starting materials. The key tetrahydroquinoline intermediates of the reaction were synthesised via a fast and effective procedure and could be isolated as such, or further reacted towards the target polyaromatic structures. The obtained products showed interesting luminescent properties and their emission, excitation and quantum yields were evaluated. [ABSTRACT FROM AUTHOR]

2,6-Diaryl-4H-tetrahydro-thiopyran-4-ones and corresponding sulfoxide and sulfone derivatives were designed to lower the major toxicity of their parent anti-kinetoplatidal diarylideneacetones through a prodrug effect. Novel diastereoselective methodologies were developed and generalized from diarylideneacetones and 2,6-diaryl-4H-tetrahydro-thiopyran-4-ones to allow the introduction of a wide substitution profile and to prepare the related S-oxides. The in vitro biological activity and selectivity of diarylideneacetones, 2,6-diaryl-4H-tetrahydro-thiopyran-4-ones, and their S-sulfoxide and sulfone metabolites were evaluated against Trypanosoma brucei brucei, Trypanosoma cruzi, and various Leishmania species in comparison with their cytotoxicity against human fibroblasts hMRC-5. The data revealed that the sulfides, sulfoxides, and sulfones, in which the Michael acceptor sites are temporarily masked, are less toxic against mammal cells while the anti-trypanosomal potency was maintained against T. b. brucei, T. cruzi, L. infantum, and L. donovani, thus confirming the validity of the prodrug strategy. The mechanism of action is proposed to be due to the involvement of diarylideneacetones in cascades of redox reactions involving the trypanothione system. After Michael addition of the dithiol to the double bonds, resulting in an elongated polymer, the latter—upon S-oxidation, followed by syn-eliminations—fragments, under continuous release of reactive oxygen species and sulfenic/sulfonic species, causing the death of the trypanosomal parasites in the micromolar or submicromolar range with high selectivity indexes. [ABSTRACT FROM AUTHOR]

A series of optically pure aziridine phosphines and their corresponding phosphine oxides were synthesized through established chemical methodologies. The compounds were systematically investigated for their biological properties. Notably, all synthesized compounds demonstrated moderate antibacterial activity only against the reference strain of Staphylococcus aureus. However, compounds 5 and 7 exhibited noteworthy cell viability inhibition of human cervical epithelioid carcinoma HeLa cells and endometrial adenocarcinoma Ishikawa cells. Further studies of these compounds revealed additional biological effects, including disruption of the cell membrane in high concentrations, cell cycle arrest in the S phase, and the induction of reactive oxygen species (ROS). Comparative analysis of the two classes of chiral organophosphorus derivatives of aziridines indicated that chiral phosphine oxides displayed significantly higher biological activity. Consequently, these findings suggest that chiral phosphine oxides may be potential candidates for the development of anticancer drugs. In light of the significant interest in preparations whose structure is based on a three-membered aziridine ring in terms of potential anticancer therapy, this research fits into the current research trend and should constitute a valuable addition to the current state of knowledge and the existing library of aziridine derivatives with anticancer properties. [ABSTRACT FROM AUTHOR]

Circularly polarized electroluminescence (CPEL) is an active area of research because of its wide application in 3D displays and anti‐counterfeiting. However, it is not trivial to obtain a high asymmetry factor for highly efficient CPELs. Herein, a highly efficient CPEL is demonstrated with a superior asymmetry factor by using a chiral phosphine‐oxide‐passivated perovskite film as an emitter. An in situ‐formed perovskite nanocrystalline (NC) film is obtained by passivation of the chiral phosphine oxide. The as‐formed film exhibits much‐enhanced photoluminescence compared with the pristine film. More importantly, the NC film exhibits excellent chiral photoluminescence with a luminescence dissymmetry factor glum as high as 5.6 × 10−3. Electrically driven light‐emitting diodes based on the NC film exhibited superior device performance with a maximum brightness of 18,783 cd m−2 and a peak external quantum efficiency of 3.6%. More encouragingly, an unprecedented electroluminescence asymmetry factor gEL of up to 0.18 is achieved because of the chiral lattice distortion of the perovskite, which is the state‐of‐the‐art among hybrid materials. [ABSTRACT FROM AUTHOR]

A convenient visible–light–promoted phosphorylation reaction of α‐diazoesters with H‐phosphine oxides for the preparation of (Z)‐phosphinic hydrazones has been explored. This reaction could be performed under mild conditions to afford a series of (Z)‐phosphinic hydrazones in moderate to good yields through photoisomerization of C=N bond. [ABSTRACT FROM AUTHOR]