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This document provides a detailed overview of the synthesis and characterization of β-hydroxyhydrophosphonic acids and their derivatives. The traditional methods for synthesizing these compounds have limitations, and the article presents a new method that uses sodium hypophosphite as a green and cost-effective phosphorus source. The reaction is catalyzed by silver trifluoromethanesulfonate and demonstrates good efficiency and functional group compatibility. The document includes information on the chemical properties of various phosphinic acids, providing data such as NMR spectra, melting points, and yields for each compound. This information can be valuable for researchers studying these compounds and their properties. [Extracted from the article]

Transition‐metal‐catalyzed coupling reactions that involve the direct functionalization of insert C−H bond represent one of the most efficient strategies for forming carbon‐carbon bonds. Herein, a palladium‐catalyzed intramolecular C−H bond arylation of triaryl phosphates is reported to access seven‐membered cyclic biarylphosphonate targets. The reaction is achieved via a unique eight‐membered palladacyclic intermediate and shows good functional group compatibility. Meanwhile, the product can be readily converted into other valuable phosphate compounds. [ABSTRACT FROM AUTHOR]

A metal-free method for the dual activation of aryl phosphinate has been developed; the P–H and P–O bonds are sequentially activated by the Tf2O/DMSO system. Without the requirement of metals and unstable P-reagents, this one-pot procedure provides a convenient and practical access to a variety of aryl phosphonates. A mechanism involving twice generation of electrophilic P-species and two SN-processes is proposed on the basis of the control experiments. [ABSTRACT FROM AUTHOR]

P-Chiral phosphines and sec-phosphine oxides (SPO) are found in a diverse range of compounds that play crucial roles in various fields, including asymmetric catalysis, materials, agrochemistry, and pharmaceutical chemistry. Herein, we describe an enantioselective Ni-catalyzed kinetic resolution of racemic sec-phosphine oxides to obtain the corresponding optically pure P-chiral phosphine oxides and sec-phosphine oxides, respectively. These products are versatile chiral phosphine building blocks that can be used to construct an extensive range of P-chiral phosphines. [ABSTRACT FROM AUTHOR]

Herein, metal-free phosphonation of N-heterocycles with diphenylphosphine oxides, promoted by easily available 1,5-diazabicyclo[5,4,0]undec-5-ene (DBU) in dimethyl carbonate (DMC) as a green solvent under an air atmosphere, is presented. This simple method can accommodate 1,2,4-triazine-3,5(2H,4H)-diones, quinoxalin-2(1H)-ones, quinoxalines and pyrazinones with diverse substituted diphenylphosphine oxides, delivering distinctive monophosphonated N-heterocycles with a broad functional group tolerance, and the transformations are also viable for post-modification of bioactive and pharmaceutical molecules. In addition to the sustainable feature of being metal- and photocatalyst-free and utilization of ambient air as an oxidant, this method efficiently achieves the gram-scale transformation, and the product was isolated through extraction and filtration, rather than column chromatography. [ABSTRACT FROM AUTHOR]

We have developed a simple and effective method for the C-3 arylation of phosphorus-containing indole compounds in the presence of CuI under mild conditions. This reaction provides a reliable method for the modification of ligands. [ABSTRACT FROM AUTHOR]

A promoter‐free chalcogenophosphorylation reaction between diverse P(O)−H reagents and chalcogenosulfonates has been developed. In the absence of metal or any other additives, these transformations proceed through a spontaneous process at room temperature, which provide a convenient and compatible approach to a broad range of selenophosphates and thiophosphates. [ABSTRACT FROM AUTHOR]

A novel strategy of bisphosphorylation of anhydrides with P(O)–H reagents via a DMAP-catalyzed and DBU-promoted process has been developed. These one-step transformations proceed efficiently to provide convenient access to a variety of P–O–C–P motif containing organophosphorus compounds. In addition, the gram-scale synthesis and the efficient recovery of the by-product highlight the sustainability and applicability of this method. [ABSTRACT FROM AUTHOR]

To elucidate the biological mechanism of yellow rind formation on watermelon, the characteristics of soil bacterial community structure in rhizosphere and endophytic bacteria in stem of yellow rind watermelon were analyzed. Based on high-throughput sequencing technology, plant stem and rhizosphere soil samples, which collected from yellow and green rind watermelons were used in this paper, respectively. The structural characteristics of the endophytic bacteria in stems and soil bacterial communities in rhizospheres of yellow and green rind watermelons were comparative studied. Firstly, significant different proportions of some dominant bacteria and abundances could be detected between yellow and rind watermelons. Meanwhile, although different abundances of endophytic bacteria could be found, but no significant differences were observed between yellow and green rind watermelons. Moreover, Gemmatimonadota, Myxococcota, WPS-2, norank_f_Gemmatimonadaceae and Bradyrhizobium were the soil dominant bacterial genera in rhizosphere of green rind watermelon. All above results suggest that differences of rhizospheric and endophytic bacteria are exactly recruited as "workers" by different watermelon phenotypes relating to rind color formations. [ABSTRACT FROM AUTHOR]

To elucidate the biological mechanism of yellow rind formation on watermelon, the characteristics of soil bacterial community structure in rhizosphere and endophytic bacteria in stem of yellow rind watermelon were analyzed. Based on high-throughput sequencing technology, plant stem and rhizosphere soil samples, which collected from yellow and green rind watermelons were used in this paper, respectively. The structural characteristics of the endophytic bacteria in stems and soil bacterial communities in rhizospheres of yellow and green rind watermelons were comparative studied. Firstly, significant different proportions of some dominant bacteria and abundances could be detected between yellow and rind watermelons. Meanwhile, although different abundances of endophytic bacteria could be found, but no significant differences were observed between yellow and green rind watermelons. Moreover, Gemmatimonadota, Myxococcota, WPS-2, norank_f_Gemmatimonadaceae and Bradyrhizobium were the soil dominant bacterial genera in rhizosphere of green rind watermelon. All above results suggest that differences of rhizospheric and endophytic bacteria are exactly recruited as "workers" by different watermelon phenotypes relating to rind color formations. [ABSTRACT FROM AUTHOR]

A TFAA/DMSO/NaF‐based system for the efficient fluorination of P(O)−H and P(O)−OH compounds has been developed. Without adding highly toxic and expensive fluorination reagents, this novel transformation provides direct and compatible access to a variety of fluorophosphonates and phosphonofluoridates in a one‐pot manner. [ABSTRACT FROM AUTHOR]

N-Phosphorylated amides continue to be an unparalleled asset for the development of pharmaceutical molecules, and the importance of this framework has inspired researchers to look for concise and efficient methods for the synthesis of this unit. In this work, a new strategy was developed in which a one-pot synthesis of N-phosphorylated amides was achieved by a three-component reaction with carboxylic acids, phosphorus chlorides and azides under mild reaction conditions. To our knowledge, this is the first study in which this framework was constructed through a multicomponent reaction, which is innovative, efficient and economical. [ABSTRACT FROM AUTHOR]

Visible-light-facilitated phosphorus radical reactions have been developed as a powerful and sustainable tool for the synthesis of various organophosphorus compounds. In general, these reactions require stoichiometric amounts of oxidants, and reductants, bases, and radical initiators, leading to uneconomical and complicated processes. Progress has been made over the past few years toward using reactions that proceed under eco-benign and mild reaction conditions. Furthermore, these reactions have broad functional group tolerance, with some facile and economical pathways. Herein, we summarize the discoveries and achievements pertaining to C–P bond formation through a visible light photocatalysis procedure with high atom economy, made by our group and other research groups. It was established that greener and more environmentally friendly approaches do not require an additional oxidant or base. Moreover, we have designed and synthesized a new type of P-radical precursor, which can take part in reactions without the requirement for any additional bases, oxidants, and additives. This breakthrough, pertaining to novel visible-light-induced transformations, will be discussed and a plausible mechanism is proposed, based on corresponding experiments and the literature. [ABSTRACT FROM AUTHOR]

A novel (pentamethylcyclopenta-1,3-dienyl)iridium(III)-catalyzed direct C–H functionalization of triarylphosphine oxides with diazo dicarbonyl compounds through carbene insertion has been developed. This strategy provides a simple and efficient route to the construction of α-arylated 1,3-dicarbonyl compounds, which are important building blocks in pharmaceutical chemistry. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed, temporary P(O) directing group assisted C–H bond arylation of carbazoles was achieved. The release of the directing group occurs spontaneously in the reaction and the mechanistic studies indicate that acid is essential for N–P bond cleavage. [ABSTRACT FROM AUTHOR]

A palladium‐catalyzed Catellani‐type reaction of indole with diethyl (iodomethyl)phosphonate has been developed. This new protocol provides an efficient and concise route to 2‐methylene phosphonate indoles, which are key synthons for the construction of indole alkaloids. [ABSTRACT FROM AUTHOR]

The low‐cost cobalt(II) catalyst has been used for the first time to achieve P(O)‐radical‐mediated bisfunctionalization of alkenes with diarylphosphine oxide and peroxides. This simple process is performed under mild conditions to afford a wide variety of phosphonation‐peroxidation products in a one‐pot manner. Computational studies are carried out to provide a theoretical support for the P(O)‐radical‐involved bisfunctionalization of alkenes. [ABSTRACT FROM AUTHOR]

A novel type of oxime phosphonate was synthesized and used in the intermolecular cascade radical addition reaction of alkenes to access β-aminophosphonates via visible-light-driven N-centered iminyl radical-mediated and redox-neutral selective C–P single-bond cleavage in an active phosphorus radical route. The procedure is characterized by its ability to achieve the construction of Csp3–P and Csp3–N bonds without the requirement for oxidants and bases. [ABSTRACT FROM AUTHOR]

An efficient strategy for the synthesis of benzazole-phosphine ligand precursors via N -heterocyclic carbene catalyzed aerobic oxidative cyclization reaction has been performed. The reaction displays broad functional group tolerance and high atom economy, and the transformation has been further applied to benzazole-phosphine ligand synthesis. [ABSTRACT FROM AUTHOR]

Phosphorus-radical participated difunctionalization reactions with unsaturated compounds have been recognized as powerful method for organic synthesis. This review covers our recent work on the application of transition metal catalyzed P-radical promoted difunctionalization for synthesis of organophosphorus compounds. [ABSTRACT FROM AUTHOR]

A Cerium(IV)‐promoted phosphinoylation‐nitratation of alkenes is established under mild conditions. In this process, Ceric ammonium nitrate (CAN) acts as a cheap phosphorus‐radical initiator, as well as a nitrate donor. Various β‐nitrooxyphosphonates are delivered in high yield in a one‐pot manner. [ABSTRACT FROM AUTHOR]

A new type of phosphine radical precursor for C—P bond formation has been developed and successfully used in visible‐light‐catalyzed phosphonation‐annulation of unsaturated sulfonamides and carboxylic acids. The catalytic process is simple and green accessible, and no additional oxidant or base is needed. Mechanistic studies suggest that the reaction proceeds via a single electron transfer pathway. A new type of phosphine radical precursor for C—P bond formation has been developed and successfully used in visible‐light‐catalyzed phosphonation‐annulation of unsaturated sulfonamides and carboxylic acids. The catalytic process is simple and green accessible, and no additional oxidant or base is needed. Mechanistic studies suggest that the reaction proceeds via a single electron transfer pathway. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and practical method for the synthesis of α,α‐difluoro‐γ‐aminophosphonates through photocatalyzed intermolecular aminodifluoromethylphosphonation of alkenes has been developed. In this reaction, difluoromethylphosphonate is used as an important fluorinated reagent. Furthermore, the mild reaction conditions, simple operation, and broad substrate scope make this protocol very practical and attractive. The derivatization reaction in the synthesis of difluoromethylphosphonated chiral binaphthylamine ligands and α,α‐difluoro‐γ‐aminophosphoric acid highlight the applicability of this method. [ABSTRACT FROM AUTHOR]

Abstract: 3‐Phosphinoylindoles are important components of biological active natural products and materials in pharmaceuticals. Herein, a new approach for the synthesis of 3‐phosphinoylindoles has been established by a Rh(III)‐catalyzed cyclization from readily accessible (2‐azidostyryl)diphenylphosphine oxides. This intramolecular transformation occurs through a unique phosphine oxide group migration and offers a straightforward route to rebuild sp2 C−P bond and construct the indole ring in single step. [ABSTRACT FROM AUTHOR]

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A Rh/Ni-catalyzed cascade sequence of allylamine isomerization and hydrophosphonylation to synthesize α-aminophosphonates has been disclosed. The reaction, which not only allows the generation of widespread valuable α-aminophosphonates under simple systems and mild conditions, but also enriches the process of olefin isomerization–addition both in catalytic systems and various reaction types. [ABSTRACT FROM AUTHOR]

An efficient metal-free tandem intramolecular oxidative C−H amination and iodization of phosphinamide was performed and a series of new phosphorus heterocyclic compounds was obtained. This method provides a concise and highly valuable pathway for the synthesis of difunctional atropoisomeric P-stereogenic phosphinamides. [ABSTRACT FROM AUTHOR]

This review describes new methods for the synthesis of chiral monophosphine ligands with menthyl phenylphosphinate as a chiral auxiliary through asymmetric Suzuki-Miyaura cross-coupling reactions and asymmetric C-H functionalization. The chiral menthyl phenylphosphinate as a chiral auxiliary is easy to prepare and the menthyl group can easily be transformed into other functional groups, with the chiral center synchronously remaining. These methodologies provide highly efficient and practical strategies for the synthesis of novel axially chiral biaryl monophosphine oxides and their corresponding phosphines. Meanwhile, these reactions are easy to handle and exhibit wide scope for substrates with excellent diastereomeric ratios. [ABSTRACT FROM AUTHOR]

Efficient asymmetric Suzuki-Miyaura coupling reactions have been employed for the first time to synthesize chiral biaryl compounds with phosphinate groups as chiral auxiliaries. A series of functionalized chiral biaryls are thereby synthesized in excellent yields and good diastereoselectivities (up to >95:5 d.r.) and axially chiral monophosphorus ligands are obtained through further functionalizations. [ABSTRACT FROM AUTHOR]

The first Cu-catalyzed cascade sp3 C–H bond oxidative functionalization of the 2-ethylazaarenes has been developed. The two different sp3 C–H bonds in 2-ethylazaarenes are selectively oxidized and four new types of bonds (C=O, C=N, C–C, C–O) are constructed in one operation. Starting from the simple substrates and cheap nitro source, this reaction provides an efficient approach to produce new kinds of isoxazolines. [ABSTRACT FROM AUTHOR]

A novel and convenient approach to the synthesis of various phosphorated indolines via a copper-catalyzed radical cascade cyclization reaction has been developed. The reaction employs cheap copper as the catalyst and K2S2O8 as the oxidant under mild conditions. Various alkenes and P-radical precursors are compatible with this transformation. Preliminary mechanistic studies reveal that the addition of the P-radical may initiate the reaction, and then oxidative cyclization may be achieved to afford the desired product. [ABSTRACT FROM AUTHOR]

An aluminum triflate-catalyzed intramolecular reaction sequence involving protonation and Mannich-like nucleophilic addition of indoles toward the concise construction of the tetrahydropyrido[1,2- a]indol-6-one skeleton is reported. This new reaction pattern employs a carbon atom as nucleophile to form a CC bond which bears one or even two quaternary carbons and leads to the dearomatization of indoles with high atom economy. [ABSTRACT FROM AUTHOR]

A convenient strategy has been developed for the preparation of various phosphine ligands in good to excellent yields through a nickel-catalyzed C-P bond-forming step. This reaction proceeded smoothly and tolerated a variety of functional groups to provide a new method for the synthesis of important phosphine ligands through the direct cleavage of a C-Cl bond. [ABSTRACT FROM AUTHOR]

The present study has been conducted to investigate the effects of vinasse and press mud (PM) (sugar industry by-products) applications on sugarcane soil microbial population, its enzyme activities and biomass carbon and nitrogen in order to work out its potential to be used as bio-friendly fertilizer. The treatments were compared with traditional chemical fertilizer (CF) applications. Vinasse and PM amended soils were found to have slightly lower pH and higher total N and C content, however, the difference was insignificant with CF amended soils. Both the treatments increased sugarcane yield compared to chemical fertilizer, but this increase was not significant in PM amended soils. The populations of fungi, bacteria and actinomycetes increased in vinasse and PM amended soils. This increase in former one was significant in PM amended soils only, and that of the latter in vinasse amended soil. The biomass C and N contents were also higher in both the treatments, however, only the former one had significant difference with CF. Amongst the soil enzymes, the activities of cellulase, phosphatase and aminopeptidase were significantly higher in PM treatment while these were at par in vinasse and CF treatments. These results showed a potential possibility of substituting chemical fertilizers with vinasse and press mud which besides improving soil health and enhancing sugarcane productivity, can also solve the problem of their disposal in free environment. [ABSTRACT FROM AUTHOR]

Silver screen: The AgNO3‐catalyzed carbon phosphorylation of alkenes occurs by an alkene addition/cyclization cascade. Ag+ reacts with Ph2P(O)H to form the crucial active intermediate 1, which promotes the reaction. This method requires a cheap, nontoxic silver salt as the catalyst and substrates for the transformation are simple and readily accessible. [ABSTRACT FROM AUTHOR]

Silberstreif: Die AgNO3 ‐ katalysierte Kohlenstoffphosphorylierung von Alkenen verläuft über eine Additions ‐ Cyclisierungs ‐ Kaskade. Ag+ reagiert mit Ph2P(O)H zur aktiven Zwischenstufe 1, die die Reaktion katalysiert. Die Methode benötigt lediglich ein preiswertes ungiftiges Silbersalz als Katalysator und ist auf einfache, leicht zugängliche Substrate anwendbar. [ABSTRACT FROM AUTHOR]

Highly selective arylation catalyzed by palladium and directed by the acetamino group provides an efficient and practical protocol for constructing unique biaryl scaffolds, which could be further transformed into different structural units found in a range of natural products. 1 Introduction 2 Highly Regioselective Halogenation 3 Highly Regioselective Arylation 3.1 With Arylboronic Acids 3.2 With Trialkoxyarylsilanes 3.3 With Simple Arenes 3.4 Further Transformations 4 Conclusion [ABSTRACT FROM AUTHOR]

In China, economic centers are far from energy storage bases, so it is significant to select a proper energy transferring mode to improve the efficiency of energy usage. To solve this problem, an optimal allocation model based on energy transfer mode was proposed after objective function for optimizing energy using efficiency was established, and then, a new Tabu search and particle swarm hybrid optimizing algorithm was proposed to find solutions. While actual data of energy demand and distribution in China were selected for analysis, the economic critical value in comparison between the long-distance coal transfer and electric power transmission was gained. Based on the above discussion, some proposals were put forward for optimal allocation of energy transfer modes in China. By comparing other three traditional methods that are based on regional price differences, freight rates and annual cost with the proposed method, the result indicates that the economic efficiency of the energy transfer can be enhanced by 3.14%, 5.78% and 6.01%, respectively. [ABSTRACT FROM AUTHOR]

A new support vector machine (SVM) optimized by an improved particle swarm optimization (PSO) combined with simulated annealing algorithm (SA) was proposed. By incorporating with the simulated annealing method, the global searching capacity of the particle swarm optimization (SAPSO) was enhanced, and the searching capacity of the particle swarm optimization was studied. Then, the improved particle swarm optimization algorithm was used to optimize the parameters of SVM ( c, σ and ε). Based on the operational data provided by a regional power grid in north China, the method was used in the actual short term load forecasting. The results show that compared to the PSO-SVM and the traditional SVM, the average time of the proposed method in the experimental process reduces by 11.6 s and 31.1 s, and the precision of the proposed method increases by 1.24% and 3.18%, respectively. So, the improved method is better than the PSO-SVM and the traditional SVM. [ABSTRACT FROM AUTHOR]

Considering multi-factor influence, a forecasting model was built. The structure of BP neural network was designed, and immune algorithm was applied to optimize its network structure and weight. After training the data of power demand from the year 1980 to 2005 in China, a nonlinear network model was obtained on the relationship between power demand and the factors which had impacts on it, and thus the above proposed method was verified. Meanwhile, the results were compared to those of neural network optimized by genetic algorithm. The results show that this method is superior to neural network optimized by genetic algorithm and is one of the effective ways of time series forecast. [ABSTRACT FROM AUTHOR]