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Organic p‐type cathodes have captured increasing attention for lithium‐organic batteries due to their high voltage output. However, because of the low electronic and ionic conductivity, the p‐type organic electrode materials often show sluggish reaction kinetics and hence low capacities and poor cyclability. In this work, three conjugated polymers (Pz‐TPPO, Pz‐TPPS, and Pz‐TPP) based on p‐type phenazine linked with triphenyl phosphine are reported with different chemical modifications of phosphorus atom. Through oxidation and sulfuration of phosphorus atoms, the electron‐accepting property strength is increased, resulting in higher electronic conductivity of Pz‐TPPO and Pz‐TPPS. It is also found that the P═O unit in Pz‐TPPO exhibits stronger Li+ coordination, which can bring anions into close proximity to the redox centers, further improving the anion shuttling during charge and discharge. All these lead to the best lithium‐organic battery performance of Pz‐TPPO, such as high voltage output (3.1–3.9 V), high reversible specific capacity (149 mAh g−1 at 0.2 A g−1) and excellent cycle stability. The potential application has also been demonstrated in Pz‐TPPO//graphite full battery. This work provides a novel strategy for designing donor–acceptor (D–A) conjugated polymer by simple phosphorus modification toward high‐performance organic batteries. [ABSTRACT FROM AUTHOR]

While organophosphorus chemistry is gaining attention in a variety of fields, the synthesis of the phosphorus derivatives of amino acids remains a challenging task. Previously reported methods require the deprotonation of the nucleophile, complex reagents or hydrolysis of the phosphonate ester. In this paper, we demonstrate how to avoid these issues by employing phosphonylaminium salts for the synthesis of novel mixed n-alkylphosphonate diesters or amino acid-derived n-alkylphosphonamidates. We successfully applied this methodology for the synthesis of novel N-acyl homoserine lactone analogues with varying alkyl chains and ester groups in the phosphorus moiety. Finally, we developed a rapid, quantitative and high-throughput bioassay to screen a selection of these compounds for their herbicidal activity. Together, these results will aid future research in phosphorus chemistry, agrochemistry and the synthesis of bioactive targets. [ABSTRACT FROM AUTHOR]

Phosphorus‐centered disbiradicals, in which the radical sites exist as individual spin doublets with weak spin‐spin interaction have not been known so far. Starting from monoradicals of the type [⋅P(μ‐NTer)2P−R], we have now succeeded in linking two such monoradical phosphorus centers by appropriate choice of a linker. To this end, biradical [⋅P(μ‐NTer)2P⋅] (1) was treated with 1,6‐dibromohexane, affording the brominated species {Br[P(μ‐NTer)]2}2C6H12 (3). Subsequent reduction with KC8 led to the formation of the disbiradical {⋅[P(μ‐NTer)]2}2C6H12 (4) featuring a large distance between the radical phosphorus sites in the solid state and formally the highest biradical character observed in a P‐centered biradical so far, approaching 100 %. EPR spectroscopy revealed a three‐line signal in solution with a considerably larger exchange interaction than would be expected from the molecular structure of the single crystal. Quantum chemical calculations revealed a highly dynamic conformational space; thus, the two radical sites can approach each other with a much smaller distance in solution. Further reduction of 4 resulted in the formation of a potassium salt featuring the first structurally characterized P‐centered distonic radical anion (5−). Moreover, 4 could be used in small molecule activation. [ABSTRACT FROM AUTHOR]

The synthesis of P‐stereogenic phosphorus compounds has gained considerable attention due to their wide applications across many research fields. Among the available strategies, transition metal‐catalyzed asymmetric transformation of pentavalent phosphoryl (H−P(O)) precursors is particularly appealing. This approach involves a direct C−P bond‐forming process, rendering it straightforward, and it employs readily available, bench‐stable H−P(O) reagents that are compatible with various metal catalysts. Recent years have witnessed significant progress in this field, with a primary focus on asymmetric C−P cross‐couplings and hydrophosphorylations. This Concept article provides a brief summary of recent progress, highlights existing challenges, and discusses future directions in this exciting area. [ABSTRACT FROM AUTHOR]

This review describes the synthesis of polyphosphorhydrazone (PPH) dendrimers,which are highly branched macromolecules, having a phosphorus atom at each branching point. The properties of these PPH dendrimers in the field of catalysis are then described. The review is organized to illustrate in the first part how the specificities of dendrimers could contribute to green chemistry. This concerns in particular the dendritic effect that is an increased efficiency (yield, enantioselectivity, etc.) when the size of the dendrimer increases, the recovery and reuse of the dendritic catalyst, the decreased leaching, and the entrapping of nanoparticles. In a second part, some even greener approaches of catalysis with dendrimers will be displayed, such as catalysis in water, switchable catalysis, and organocatalysis (nometal used). Different types of catalytic reactions have been studied, such as Stille, Suzuki and Sonogashira couplings, Knoevenagel condensations, Michael additions, asymmetric allylic alkylations, O- and N-arylation and vinylation reactions, [2+2+2]-cycloaddition reactions, isomerization of 1-octan-3-ol, Friedel--Crafts acylations, Heck reactions, hydrogenations, hydrations, transfer hydrogenations, amination of β-dicarbonyl compounds, etc. [ABSTRACT FROM AUTHOR]

While organophosphorus chemistry is gaining attention in a variety of fields, the synthesis of the phosphorus derivatives of amino acids remains a challenging task. Previously reported methods require the deprotonation of the nucleophile, complex reagents or hydrolysis of the phosphonate ester. In this paper, we demonstrate how to avoid these issues by employing phosphonylaminium salts for the synthesis of novel mixed n-alkylphosphonate diesters or amino acid-derived n-alkylphosphonamidates. We successfully applied this methodology for the synthesis of novel N-acyl homoserine lactone analogues with varying alkyl chains and ester groups in the phosphorus moiety. Finally, we developed a rapid, quantitative and high-throughput bioassay to screen a selection of these compounds for their herbicidal activity. Together, these results will aid future research in phosphorus chemistry, agrochemistry and the synthesis of bioactive targets.

The supramolecular recognition of anions is increasingly harnessed to achieve the self‐assembly of supramolecular architectures, ranging from cages and polymers to (pseudo)rotaxanes. The cyanostar (CS) macrocycle has previously been shown to form 2 : 1 complexes with organophosphate anions that can be turned into [3]rotaxanes by stoppering. Here we achieved steric control over the assembly of pseudorotaxanes comprising the cyanostar macrocycle and a thread that is based, for the first time, on organo‐pyrophosphonates. Subtle differences in steric bulk on the threads allowed formation of either [3]pseudorotaxanes or [2]pseudorotaxanes. We demonstrate that the threading kinetics are governed by the steric demand of the organo‐pyrophosphonates and in one case, slows down to the timescale of minutes. Calculations show that the dianions are sterically offset inside the macrocycles. Our findings broaden the scope of cyanostar‐anion assemblies and may have relevance for the design of molecular machines whose directionality is a result of relatively slow slipping. [ABSTRACT FROM AUTHOR]

Dendrimers, being highly branched monodispersed macromolecules, predominantly exhibit identical terminal functionalities within their structural framework. Nonetheless, there are instances where the presence of two distinct surface functionalities becomes advantageous for the fulfilment of specific properties. To achieve this objective, one approach involves implementing Janus dendrimers, consisting of two dendrimeric wedges terminated by dissimilar functionalities. The prevalent method for creating these structures involves the synthesis of dendrons that possess a core functionality that complements that of a second dendron, facilitating their coupling to generate the desired dendrimers. In this comprehensive review, various techniques employed in the fabrication of phosphorus-based Janus dendrimers are elucidated, displaying the different coupling methodologies employed between the two units. The advantages of phosphorus dendrimers over classic dendrimers will be shown, as the presence of at least one phosphorus atom in each generation allows for the easy monitoring of reactions and the confirmation of purity through a simple technique such as 31P NMR, as these structures typically exhibit easily interpretable patterns. [ABSTRACT FROM AUTHOR]

Dendrimers, being highly branched monodispersed macromolecules, predominantly exhibit identical terminal functionalities within their structural framework. Nonetheless, there are instances where the presence of two distinct surface functionalities becomes advantageous for the fulfilment of specific properties. To achieve this objective, one approach involves implementing Janus dendrimers, consisting of two dendrimeric wedges terminated by dissimilar functionalities. The prevalent method for creating these structures involves the synthesis of dendrons that possess a core functionality that complements that of a second dendron, facilitating their coupling to generate the desired dendrimers. In this comprehensive review, various techniques employed in the fabrication of phosphorus-based Janus dendrimers are elucidated, displaying the different coupling methodologies employed between the two units. The advantages of phosphorus dendrimers over classic dendrimers will be shown, as the presence of at least one phosphorus atom in each generation allows for the easy monitoring of reactions and the confirmation of purity through a simple technique such as 31P NMR, as these structures typically exhibit easily interpretable patterns.

The activation of C−Br bonds in various bromoalkanes by the biradical [⋅P(μ‐NTer)2P⋅] (1) (Ter=2,6‐bis‐(2,4,6‐trimethylphenyl)‐phenyl) is reported, yielding trans‐addition products of the type [Br−P(μ‐NTer)2P−R] (2), so‐called 1,3‐substituted cyclo‐1,3‐diphospha‐2,4‐diazanes. This addition reaction, which represents a new easy approach to asymmetrically substituted cyclo‐1,3‐diphospha‐2,4‐diazanes, was investigated mechanistically by different spectroscopic methods (NMR, EPR, IR, Raman); the results suggested a stepwise radical reaction mechanism, as evidenced by the in‐situ detection of the phosphorus‐centered monoradical [⋅P(μ‐NTer)2P‐R].< To provide further evidence for the radical mechanism, [⋅P(μ‐NTer)2P‐Et] (3Et⋅) was synthesized directly by reduction of the bromoethane addition product [Br‐P(μ‐NTer)2P‐Et] (2 a) with magnesium, resulting in the formation of the persistent phosphorus‐centered monoradical [⋅P(μ‐NTer)2P‐Et], which could be isolated and fully characterized, including single‐crystal X‐ray diffraction. Comparison of the EPR spectrum of the radical intermediate in the addition reaction with that of the synthesized new [⋅P(μ‐NTer)2P‐Et] radical clearly proves the existence of radicals over the course of the reaction of biradical [⋅P(μ‐NTer)2P⋅] (1) with bromoethane. Extensive DFT and coupled cluster calculations corroborate the experimental data for a radical mechanism in the reaction of biradical [⋅P(μ‐NTer)2P⋅] with EtBr. In the field of hetero‐cyclobutane‐1,3‐diyls, the demonstration of a stepwise radical reaction represents a new aspect and closes the gap between P‐centered biradicals and P‐centered monoradicals in terms of radical reactivity. [ABSTRACT FROM AUTHOR]

Haloazaphosphatranes are the halogenated parents of proazaphosphatranes, also known as Verkade's superbase. While the synthesis of iodo‐, bromo‐ and chloroazaphosphatranes was reported more than thirty years ago by J. G. Verkade, the first synthesis of fluoroazaphosphatranes was only described in 2018 by Stephan et al. Currently, no common and versatile procedure exists to access fluoroazaphosphatranes platform with different structural characteristics. In this report, a new and simple synthesis of this class of compounds was developed based on the nucleophilic attack of the fluoride anion on chloroazaphosphatrane derivatives with good to high isolated yields for the corresponding fluoroazaphosphatranes (70–92%). The scope of the reaction was widened to fluoroazaphosphatranes bearing various substituents and X‐ray molecular structures of two of them are reported. The stability of fluoroazaphosphatranes toward nucleophilic solvents like water has been investigated. As they revealed much more robust cations than their chloroazaphosphatrane parents, their chloride salts were tested as organocatalysts for the formation of cyclic carbonates from epoxides and CO2. Fluoroazaphosphatranes proved to be both efficient and stable catalytic systems for CO2 conversion with catalytic activities similar to those of azaphosphatranes, and no decomposition of the cation was observed at the end of reaction. [ABSTRACT FROM AUTHOR]

The construction of chiral phosphorus molecules with asymmetric center on the phosphorus atom has always been considered to be challenging in synthetic chemistry. Such P-stereogenic compounds possess many unique properties allowing many potential applications in natural products synthesis, pharmaceuticals as well as ligands in asymmetric organometallic catalysis. This increasing importance of P-stereogenic compounds has driven chemists to develop sophisticated strategies over the years to construct chiral phosphorus compounds. In this review, we aim to discuss the methodologies for the construction of P-stereogenic centers that were developed from 2005 to 2020. The review has been organized into seven sections according to their respective reaction principles beginning with desymmetrization, followed by phosphonoalkylation and phosphonoarylation, asymmetric addition, deprotonation, ring-closing metathesis, the use of organolithiums and Grignard reagents together with chiral auxiliaries and ending with kinetic resolution.

The time-dependent wave packet (TDWP) method was applied to investigate the quantum reaction mechanisms of title reaction, obtaining the state-specified (v = 0, j = 0) reaction probability, integral cross sections and rate constants. [Display omitted] • The quantum effect of the title reaction are studied. • The reaction mechanism of title reaction is ruled by the collision energy. • The reaction probability, integral cross sections and rate constants are calculated. • The rate constants agree well with expermental results. The title reaction is thought to be important for the astronomical PO formation, which may contribute to the generation of bioavailable H 3 PO 3. Using quasi-classical trajectory (QCT) method, the state-specified (v = 0, j = 0) rate constant of this reaction was calculated. The comparison with previous temperature-averaged QCT rate constant shows that the effect of ro-vibrational excitation is relatively small below 2000 K. Then, the time-dependent wave packet (TDWP) method was applied to investigate the quantum reaction mechanisms, obtaining the state-specified (v = 0, j = 0) reaction probability, integral cross sections and rate constants. The number of partial waves and the integral interval of collision energy considered were rigorously tested to ensure the convergence of the TDWP rate constant below 2000 K. The TDWP rate constant agrees better to the latest experimental results at 291 to 685 K than those from the two QCT calculations. Also, the TDWP calculations can produce relatively reliable rate constants at 700 to 2000 K, where the Arrhenius formula fitted by experimental results ignores the temperature dependence of the activation energy. The calculated rate constants are helpful for modelling the phosphorus chemistry and determining the abundances of the P-bearing species in interstellar media (ISM). [ABSTRACT FROM AUTHOR]

Supply of phosphorus (P) as an agricultural input depends on a limited mineral rock phosphate reserve, but inefficient use means this resource is not being used sustainably. Moreover, losses of P from historically accumulated soil reserves can cause substantial environmental harm. Development of sustainable P management will require optimization of P use efficiency, with this needing a better understanding of the distribution and chemical behaviour of P in soils, including both P applied as a fertilizer and native P. In this review, we discuss in-situ methods for microscopic mapping of P distribution, speciation and plant-available P fractions in soils, including scanning electron microscopy-based energy-dispersive X-ray spectroscopy, nanoscale secondary ion mass spectroscopy, X-ray fluorescence microscopy (and associated X-ray absorption spectroscopy), Raman and infrared spectroscopies, diffusive gradients in thin films coupled with laser ablation inductively coupled plasma mass spectrometry or colorimetry, and autoradiography. These methods can complement the traditional (bulk) methods for P analysis as well as deliver valuable information in their own right or in conjunction as part of an imaging cascade. We compare the merits and limitations of these techniques, which can serve to play a key role in answering questions about P behaviour in soil, from the microscopic to macroscopic scale, and provide some examples of how they may support researchers in their particular research. [ABSTRACT FROM AUTHOR]

It is worth mentioning that higher temperatures, for the same reaction time, allows introducing higher nitrogen contents; however, all temperature dependent lines fall down onto a temperature of ca. 550 °C, below which no nitrogen is introduced as it was shown in alkali-lead metaphosphate glasses [[13]]. However, and because of the release of water as a product of the ammonolysis reaction, the oxynitride glasses will content some residual water that will affect negatively to the Nd luminescence as the nitrogen content in increased due to non-radiative quenching by OH ions in the glass. Keywords: Ceramics; glasses; nitrogen; phosphorus chemistry; solid state chemistry; SSC 2021 EN Ceramics glasses nitrogen phosphorus chemistry solid state chemistry SSC 2021 189 195 7 03/11/22 20220201 NES 220201 Article note: A collection of invited papers based on presentations at the 14 th International Conference on Solid State Chemistry (SSC 2021) held in Trencin, Slovakia, June 13-17, 2021. [Extracted from the article]

Reactions involving the transfer of phosphorus-containing groups are of key importance for maintaining life, from biological cells, tissues and organs to plants, animals, humans, ecosystems and the whole planet earth. The sustainable utilization of the nonrenewable element phosphorus is of key importance for a balanced phosphorus cycle. Significant advances have been achieved in highly selective and efficient biocatalytic phosphorylation reactions, fundamental and applied aspects of phosphorylation biocatalysts, novel phosphorylation biocatalysts, discovery methodologies and tools, analytical and synthetic applications, useful phosphoryl donors and systems for their regeneration, reaction engineering, product recovery and purification. Biocatalytic phosphorylation reactions with complete conversion therefore provide an excellent reaction platform for valuable analytical and synthetic applications.

Organophosphorus compounds have numerous useful applications, from versatile ligands and nucleophiles in the case of trivalent organophosphorus species to therapeutics, agrochemicals and material additives for pentavalent species. Although phosphorus chemistry is a fairly mature field, the construction of C–P(V) bonds relies heavily on either prefunctionalized substrates such as alkyl or aryl halides, or requires previously oxidized bonds such as C=N or C=O, leading to potential sustainability issues when looking at the overall synthetic route. In light of the recent advances in photochemistry, using photons as a reagent can provide better alternatives for phosphorylations by unlocking radical mechanisms and providing interesting redox pathways. This review will showcase the different photomediated phosphorylation procedures available for converting C–H bonds into C–P(V) bonds. 1 Introduction 1.1 Organophosphorus Compounds 1.2 Phosphorylation: Construction of C–P(V) Bonds 1.3 Photochemistry as an Alternative to Classical Phosphorylations 2 Ionic Mechanisms Involving Nucleophilic Additions 3 Mechanisms Involving Radical Intermediates 3.1 Mechanisms Involving Reactive Carbon Radicals 3.2 Mechanisms Involving Phosphorus Radicals 3.2.1 Photoredox: Direct Creation of Phosphorus Radicals 3.2.2 Photoredox: Indirect Creation of Phosphorus Radicals 3.2.3 Dual Catalysis 3.3 Photolytic Cleavage 4 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

2-R-1,3-Benzoxaphospholes (R-BOPs) are examples of fluorescent conjugated materials possessing low coordinate phosphorus centers. A series of 2-( p -XC 6 H 4 )-BOPs (X = H, Cl, Br, Me, OMe) react with [W(CO) 5 (NCMe)] to produce the crystalline complexes [W(CO) 5 (2-Ar-BOP)] ( 2a - e ). All complexes were characterized by NMR spectroscopy and by single crystal X-ray diffraction. The crystal structures all displayed extensive π-stacking of the BOP ligands and gear locking of the CO groups. Addition of the protecting [W(CO) 5 ] group to the BOPs was discovered to significantly diminish fluorescence of the BOP moiety. [ABSTRACT FROM AUTHOR]

A dichloro-cycloazatriphosphane that incorporates a cyclic NP3 backbone could be synthesized using knowledge gained from the chemistry of N2P2 and P4 ring systems. It fills the gap between the congeneric compounds [ClP(μ-NR)]2 and [ClP(μ-PR)]2 (R=sterically demanding substituent), and thus contributes to the systematic development of nitrogen-phosphorus chemistry in general. The title compound was studied with respect to its formation via a labile aminodiphosphene, which readily underwent different rearrangement reactions depending on the solvent. All compounds were fully characterized by experimental and computational methods. [ABSTRACT FROM AUTHOR]

The versatile reactivity of hexachlorocyclotriphosphazene (N3P3Cl6) has been developed for the synthesis of specifically engineered dendrimers. Dendrimers are hyperbranched macromolecules built by concentric layers constituted of associated monomeric units. Many of the properties of dendrimers depend on the type of their surface (terminal) functions, which are generally all identical. For some specific purposes, it is desirable to have one function that is different at the level of the core. Hexachlorocyclotriphosphazene offers the possibility to differentiate the reactivity of one (or more) Cl from the others, for producing specifically engineered dendritic tools. These specific reactions on N3P3Cl6 have produced highly dense dendrimers, Janus dendrimers (two faces), tools for functionalizing materials, with uses as catalysts, as chemical sensors, for trapping CO2, for the culture of cells, or for imaging biological events. These properties will be emphasized in this review. [ABSTRACT FROM AUTHOR]

A sequential fractionation method proposed by Jiang and Gu (1989) distinguished three types of calcium phosphates (Ca-P) according to their different plant availabilities. Three extractants, NaHCO 3 , NH 4 Ac, and H 2 SO 4 were used to extract Ca 2 -P, Ca 8 -P, and Ca 10 -P types, respectively, from soil. This sequential fractionation method was tested and modified for analyzing the P chemistry of a calcareous soil. The solubility test and the model diagrams of the stability of the major Ca-P minerals showed that NaHCO 3 was able to extract brushite (Ca 2 -P type), and NH 4 Ac extracted brushite and β-tricalcium P (Ca 8 -P type) as well as hydroxyapatite (Ca 10 -P type). Therefore the P forms targeted by extraction with NH 4 Ac should include both Ca 8 -and Ca 10 -P types. The sum of the P extracted by all extractants in the sequential fractionation method in the calcareous soil was in agreement with the total P measured by the perchloric acid digestion method. A proportion of organic P measured by the sequential fractionation method was in agreement with the result from solution 31 P NMR spectroscopy. This study showed that the modified sequential fractionation method and its target P forms would be useful for quantifying and characterizing inorganic and organic P in a calcareous soil, even though it should be used in combination with other techniques, such as solution 31 P NMR spectroscopy. [ABSTRACT FROM AUTHOR]

We present recent advances in the understanding of the reduction of optically pure hydroxyalkylphosphinates and phosphine oxides, which represent key intermediates for the preparation of P-stereogenic ligands. Their reduction leads to P-chiral phosphinites and phosphines, respectively, and occurs stereospecifically with inversion of configuration using BH3·THF, which plays three roles: activating, reducing and protecting agent. The formation of by-products as hydroxyalkyl secondary phosphine-boranes has also been studied. [ABSTRACT FROM AUTHOR]

The synthesis and some key reactions of the cyclotetraphosphane[ClP(μ-PMes*)]2(2, Mes*= 2,4,6-tri-tert-butylphenyl) with Lewis acids and reducing agents are discussed. All products were fully characterized, including single crystal X-ray diffraction, spectroscopic methods as well as computational studies. [ABSTRACT FROM AUTHOR]

Intense efforts by many research groups for more than 50 years have been directed at biomimetic approaches to understand how enzymes achieve their remarkable rate accelerations. Nevertheless, it was noted in 2003 that, despite numerous efforts to design models for catalyzing the cleavage of such species as phosphate diesters, 'none of the several models so far described approaches the enormous catalytic efficiency of natural enzymes'. The same could be said for biomimetics of other enzymes promoting acyl or phosphoryl transfer reactions, particularly those mediated by metal ions such as Zn(II). Clearly other important factors were being overlooked or awaiting discovery. In this manuscript we describe two important effects that we have implemented to accelerate metal ion catayzed phosphoryl and acyl transfer reactions. The first of these relates to a medium effect where the polarity of the solution, as measured by dielectric constant, is reduced from that of water ( ε = 78) to values of 31.5 and 24.3 when the solvent is changed to methanol or ethanol. Among organic solvents these light alcohols are closest to water in terms of structure and properties as well as retaining important H-bonding properties. The second important effect involves a known but difficult to demonstrate mode of catalysis where the leaving group (LG) in a solvolysis reaction is accelerated as it becomes progressively poorer. In the cases described herein, the LG's propensity to depart from a substrate during the course of reaction is accelerated by coordination to a metal ion in a process known as leaving group assistance, or LGA. These two effects can each impart accelerations of 109-1017 for certain metal ion catalyzed reactions relative to the corresponding solvent, or base induced reactions. [ABSTRACT FROM AUTHOR]

The living anionic polymerization of the phosphaalkene, MesP=CPh 2 (PA), affords a series of poly(methylenephosphine) (PMP) homo- and block co-polymers with styrene (S). Specifically, PMP m (m = 30, 40, 50, 50), PS n – b –PMP m (n , m = 100,29; 100,50; 50,30; 51, 62) and PMP m – b –PS2 n – b –PMP m (2 n , m = 100,4; 200,8; 400,16; 400,24) have been prepared and characterized. Analysis by GPC-MALS-V showed that all samples were monodisperse, displayed narrow dispersities (Đ = 1.03–1.29), and generally had molecular weights within ±(2–26%) of those targeted from the monomer-to-initiator ratios. All homo- and co-polymers displayed a single T g in their DSC chromatograms with the transition temperature for the copolymers being in between those of the corresponding homopolymers. These transitions appear to be dependent on both the copolymer composition and the corresponding chain lengths. [Display omitted] • Living anionic copolymerization of a phosphaalkene with styrene is accomplished. • Diblock and triblock copolymers contain functional phosphine groups. • Phosphine homopolymers have high glass transition temperatures (ca. 150 °C). [ABSTRACT FROM AUTHOR]

Despite almost hundred years of dedicated research, the synthesis of phospholipids remains a challenge. Here, we briefly review important trends and point out possible future directions that might lead to interesting new probes for the membrane environment. An improved liposome purification and concentration protocol rounds up the article.

Abstract: Laboratory incubation was conducted for 120days to study the fate of phosphorus in poultry (PM), cattle (CM) and goat manures (GM). Phosphorus mineralized from manure was dependent on total P, Al and Fe content. Manures improved P availability in the order: PM>CM>GM; however, the highest amount of P was fixed or immobilized between 10 and 70days of incubating with CM and GM. Fixation and immobilization of mineralized P from poultry manure was negligible probably due to the high total P and the low amount of Al and Fe. Generally, manure application reduced the ability of the soil to fix P. More than 90% of the manure P was either immobilized or fixed by the soil. The relationship between the amount of P released and time was cubic. Improvement of the C:P ratio of CM and GM would be an option to enhance their agronomic use as fertilizer P source. [Copyright &y& Elsevier]

Abstract: The chemical mechanism of the 1PN formation was successfully studied by using the CCSD(T)/6-311++G(3df,3pd) level of theory. The 1NH3 + 3PH and 4P+NH3 reaction paths are not energetically favorable to form the 1PN molecule. However, the 3NH+ 3PH, 4N+ 3PH3, 4N+ 3PH, 4P+ 3NH, and 4P+ 2NH2 reaction paths to form the 1PN molecule are only energetically favorable by taking place through specific transition states to form the 1PN molecule. The NH3 + 3PH, 4N+ 1PH3, NH3 + 4P, and 4N+ 2PH2 reactions are spin-forbidden and the probability of hopping for these reactions was estimated to be 0 by the Landau–Zener theory. This is the first detailed study on the chemical mechanism for the 1PN formation. [Copyright &y& Elsevier]

The possible role of phosphoryl amino acids for biomolecular origins is briefly reviewed. Peptide formation, ester formation, ester exchange on phosphorus and N to O migration occurred when the N-phosphoryl amino acid was incubated at room temperature. Short nucleotides and peptides were formed when nucleoside was reacted with N-phosphoryl amino acid at room temperature. Serine and threonine residues in their conjugate with different nucleosides (mediated with phosphorus) showed different self-cleavage activities. N-phosphoryl Histine and Ser-His dipeptide could cleave nucleic acids, proteins and esters in neutral medium. Based on a simple model, a pathway of `co-evolution of protein and nucleic acid' was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Alternative synthetic methods in phosphorus chemistry. • Pyrazolyl-substituted phosphanes reveal a versatile potential in synthetic chemistry. • Pyrazolyl-substituents are amenable, potentially recyclable leaving groups. • Pyrazolylphosphanes are feasible, easy to handle and sustainable alternative to the related chloro-phosphanes. This Minireview aims to provide an overview on the chemistry of pyrazolyl-substituted phosphorus compounds with focus on their preparation and especially on their synthetic application. The majority of these compounds, in particular tripyrazolylphosphanes, are used as multidentate ligands in coordination chemistry. However, these compounds bear a versatile potential in e.g. condensation reactions (or solvolysis), salt metathesis reactions, deoxygenation reactions or P–P bond formation reactions (via condensation or P–N/P–P bond metathesis), in which the respective pyrazolyl-substituents act as amenable leaving group. The reactions involving pyrazolylphosphanes typically run under mild conditions, are often very selective and the released pyrazole can be potentially recycled, rendering these compounds a more feasible and sustainable alternative to the related chloro-phosphanes. [ABSTRACT FROM AUTHOR]

Barleygrass (Hordeum leporinum) from Australian low-P (phosphorus) soils and commercial barley (H. vulgare) with high fertilizer requirements were grown in solution culture at 3 levels of P supply. The high-P-adapted barley produced more biomass at all levels of P supply and was more responsive to added P in terms of rate of tillering, rate of leaf production, final leaf size, and therefore total shoot weight compared to barleygrass. In both species root: shoot ratio decreased in response to improved tissue P status, even at P levels where total biomass did not respond to P supply. Removal of endosperm reserves of barley reduced total biomass to a greater extent than it altered phosphate absorption rate, thus increasing tissue P status and making plants less responsive to added P. Similarly, barleygrass had a slower growth rate but a comparable P absorption rate to that of barley. Thus barleygrass also accumulated tissue P and was unresponsive to added P. All phosphorus chemical fractions increased in response to improved tissue P status, but to differing extents (inorganic-P > nucleic acid-P > lipid-F > ester-P), suggesting that all P fractions (particularly inorganic P) serve, in part, a storage function. Both barleygrass and barley without endosperm had higher concentrations of all P fractions (particularly inorganic P) than did unaltered barley, but this was due entirely to their higher P status (due to slow growth) rather than to any major difference in P metabolism between species. We conclude that slow growth is more important than interspecific differences in P metabolism, P absorption, or efficiency of P utilization in explaining the success of barleygrass and other low-P-adapted species on infertile soils. [ABSTRACT FROM AUTHOR]

Phosphorus-containing dendrimers are defined as dendrimers having at least one phosphorus atom at each branching point. In this review, we will show how phosphorhydrazone dendrimers can be modified at will at the level of the core and of the branches, to afford specific properties, such as fluorescence to image biological events. Accelerated methods of synthesis of phosphorus (one step for one generation) will be also displayed, as well as the specific reactivity of P=N-P=S linkages obtained in most of these accelerated method of synthesis, which has led to particularly original dendritic architectures, such as dendrons included in dendrimers. Finally, we will display how modifications of the internal structure of a series of dendrimers having the same type and number of terminal functions can deeply modify their biological anti-inflammatory properties. Among the six critical nanoscale design parameters (CNDP), we will show how two of them, i.e., architecture and elemental composition, have been particularly engineered to modify phosphorus-containing dendrimers, in order to fulfill the desired properties. [ABSTRACT FROM AUTHOR]