3,049 results on '"*PHOSPHITES"'
Search Results
2. Harnessing the Reactivity of ortho -Alkynylaldehydes: Silver Triflate Catalyzed Regioselective Synthesis of Phosphonylated Fluorescent Molecules.
- Author
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Thakur, Deepika, Meena, Shivam A., Sushmita, Sushmita, and Verma, Akhilesh K.
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SILVER catalysts , *BIOCHEMICAL substrates , *DIPHENYLPHOSPHINE , *QUINOLINE , *PHOSPHITES - Abstract
An efficient approach for the facile synthesis of phosphonylated 1,3-dihydrofuro[3,4- b ]quinolines and dihydrofuro[3,4- b ]pyridines is developed. Reaction proceeds by the formation of new C–P and C–O bonds affording Z -selective phosphonylated products at room temperature. Diphenylphosphine oxides and dialkyl phosphites are explicitly incorporated into the carbonyl carbon of o -alkynylaldehydes in good to excellent yields. The reaction exhibits mild conditions, broad substrate scope, and the formation of three new bonds in the presence of a silver catalyst. The mechanistic studies revealed that the reaction proceeded via an ionic pathway in a 5- exo -dig manner to give Z -selective products, which was validated by X-ray crystallographic studies. Photophysical studies of selected compounds revealed the emission maxima in the range of 455 nm. [ABSTRACT FROM AUTHOR]
- Published
- 2025
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3. Controlled Conversion of Metal–Organic Frameworks to Ultrathin Phosphite Nanosheet Arrays for High-Performance Supercapacitors.
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Huang, Mengya, Zhang, Xiudu, Liu, Ruonan, and Ni, Yonghong
- Abstract
Transition metal phosphites are attracting increased attention in the field of electrochemistry due to their open-framework structure, superior conductivity, and high stability. In this work, Ni
11 (HPO3 )8 (OH)6 (Ni-POH) nanosheet arrays were prepared from a hexamethylenetetramine solution containing varying amounts of Ni-(NO3 )2 ·6H2 O, employing plate-like phosphonate-based metal–organic frameworks (Ni-PMOF) as both the template and the phosphorus source. Also, bimetallic phosphites Ni/Co-POH-x could be obtained by replacing Ni-(NO3 )2 ·6H2 O with a mixture of Ni-(NO3 )2 ·6H2 O and Co-(NO3 )2 ·6H2 O in certain molar ratios, where x is the molar ratio of the added Ni/Co. Experiments revealed that among as-prepared phosphites, Ni/Co-POH-2 exhibited the most uniform nanosheet morphology, the biggest specific surface area, the highest structural stability, and the optimum electrochemical performance as a supercapacitor electrode material. At a current density of 1 A g–1 , the specific capacitance of Ni/Co-POH-2 reached 1905.60 F g–1 . Notably, the asymmetric supercapacitors assembled with activated carbon (Ni/Co-POH-2//AC) exhibited a high energy density of 36.59 Wh kg–1 at 0.85 kW kg–1 . After 5000 cycles, the capacitance retention was 67.98%, showing excellent cycle stability. The present work provides a useful attempt for synthesizing MOF-derived phosphite electrode materials with a high electrochemical storage performance. [ABSTRACT FROM AUTHOR]- Published
- 2024
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4. Recent Advances in the Synthesis of Commercially Available Phosphite Antioxidants.
- Author
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Zhu, Yuliang, Liu, Xinyue, Tang, Ying, Xu, Kexin, Tang, Xin, Zhu, Longzhi, and Xiong, Biquan
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INDUSTRIAL goods , *POLYMERS , *PHOSPHITES , *ANTIOXIDANTS , *PHENOL - Abstract
Phosphite antioxidants exhibit superior anti‐aging and color‐stabilizing properties when incorporated into polymer materials. Their synergistic antioxidative effects are particularly noteworthy when used in combination with hindered phenol antioxidants and other primary antioxidants, serving as effective secondary antioxidants, displaying noteworthy synergistic antioxidation effects. This review systematically classifies the synthetic methods for phosphite antioxidants into three distinct categories based on the types of starting materials: synthesis from phosphorus trichloride, phosphorus‐containing esters, and white phosphorus. Additionally, it delineates the reaction mechanisms associated with these approaches and provides an overview of future potential research directions and applications for organophosphorus antioxidants. [ABSTRACT FROM AUTHOR]
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- 2024
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5. In Situ Universal Construction of Thiophosphite/MXene Hybrids via Lewis Acidic Etching for Superior Sodium Storage.
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Zhong, Longsheng, Yue, Ming, Liang, Yazhan, Xi, Baojuan, An, Xuguang, Xiao, Yanhe, Cheng, Baochang, Lei, Shuijin, and Xiong, Shenglin
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ELECTRIC conductivity , *ION transport (Biology) , *STRUCTURAL stability , *X-ray diffraction , *FUSED salts , *ELECTRIC batteries - Abstract
Metal thiophosphite has demonstrated promising application potential as an anode material for sodium‐ion batteries. Nevertheless, the intrinsic low electrical conductivity and drastic volume expansion impede its commercialization. Herein, a series of metal thiophosphite/Ti3C2Tx (metal = Fe, Ni, Co, and Cd) composites are constructed via Lewis acidic molten salt etching followed by synchronous phospho‐sulfurization. The Ti3C2Tx substrate endows the thiophosphite/Ti3C2Tx hybrids with high electrical conductivity. Importantly, thiophosphite grown on the MXene layers exhibits a 3D cross‐linked structure, which not only facilitates electron/ion transport, but also maintains robust structural stability owing to the space confinement effect. As a proof of concept, FePS3/Ti3C2Tx demonstrates remarkable rate performance (827.4 and 598.1 mAh g−1 at 0.1 and 10 A g−1, respectively) along with long‐term cycling stability (capacity retention of 93.7% after 2000 cycles at 5 A g−1). Impressively, the FePS3/Ti3C2Tx//NVPO full cell exhibits a high reversible capacity of 396.8 mAh g−1 over 1350 cycles at 2 A g−1. The sodium storage mechanism of FePS3/Ti3C2Tx anode is further unveiled through in situ XRD/ex situ HRTEM characterizations and theoretical calculations. This work provides a fresh perspective on enhancing the electrochemical performance of thiophosphite through the in situ construction of thiophosphite/Ti3C2Tx hybrids. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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6. The Addition of α-Hydroxy-benzylphosphonates to Dialkyl Acetyl-enedicarboxylates; Catalytic Hydrogenation of the Adducts.
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Milen, Mátyás, Bese, Cintia, Kovács, Csenge, Dancsó, András, and Keglevich, György
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CATALYTIC hydrogenation , *ISOMERS , *ALKYLATION , *HYDROGENATION , *PHOSPHITES - Abstract
α-Hydroxy-benzylphosphonates obtained by the Pudovik reaction of substituted benzaldehydes and dialkyl phosphites were added to the triple bond of dialkyl acetylenedicarboxylates. Optimum conditions involved a 24 hours stirring in the presence of 10% diazabicycloundecene in dichloromethane to afford the adducts as a mixture of predominant E - and a minor Z -isomers in 75–90% yields after flash chromatography. The structures of the geometrical isomers were confirmed by NOE- and ROE-measurements. Catalytic hydrogenation of the olefinic moiety of the adducts led to the diastereoisomers of corresponding saturated derivatives. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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7. Synthesis of functionalized N-acylated amino acids containing 3- and 4-coordinated phosphorus moieties.
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Bubnov, Yu. N., Prishchenko, A. A., Livantsov, M. V., Novikova, O. P., Livantsova, L. I., and Baranin, S. V.
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ORGANIC chemistry , *ORGANIC compounds , *AMINO acids , *ESTERS , *PHOSPHITES - Abstract
A convenient synthesis of functionalized N-acylated amino acids containing 3- and 4-coordinated phosphorus moieties as well as N-alkoxycarbonyl groups has been developed. Aminomethylation of tricoordinated phosphorus acid esters with N-chloromethylsubstituted N-alkoxycarbonylamino acids proceeds under mild conditions and affords new types of target products of different structures. The resulting compounds are of interest as promising biologically active substances, effective extractants, and water-soluble polydentate ligands. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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8. Catalytic Activation of Bis(2,2,2‐trifluoroethyl) Phosphite with Hf(IV) for the Synthesis of Mixed Dialkyl Phosphites.
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Mrdović, Dario, Saito, Yuki, and Kobayashi, Shū
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ACID catalysts , *LEWIS acids , *PHOSPHITES , *CATALYSTS , *METALS - Abstract
We developed a second generation of Lewis acid catalyst enabling selective and user‐friendly phosphonylation of diverse alcohols. This one‐pot method utilizes P(III) reagent bis(2,2,2–trifluoroethyl) phosphite under mild conditions. Exploring the influence of metal selection in Lewis acid catalysts revealed four highly active complexes for alcohol phosphonylation: Zn(II), Al(III), Zr(IV), and Hf(IV). Notably, Hf(IV) displayed superior selectivity compared to the previously developed Zn(II) catalyst. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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9. Synthesis of Chromone‐3‐phosphonates via Arbuzov‐Type C−P Cross Coupling from o‐Hydroxyphenyl Enaminones and Phosphites.
- Author
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Cao, Dingsheng, Wan, Jie‐Ping, and Liu, Yunyun
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IODINATION , *PHOSPHITES , *ANNULATION , *PALLADIUM , *CATALYSIS - Abstract
With an in situ C−H iodination tactic, a method for the synthesis of chromone‐3‐phosphonates was developed with trialkyl/triaryl phosphites as the reaction partners of o‐hydroxyphenyl enaminones by palladium catalysis. The product formation consists of cascade C−H iodination, chromone annulation, and Arbuzov‐type C−P cross coupling as major transformations. In addition to providing an enaminone‐based synthetic method to chromone‐3‐phosphonates, the work shows the advantage of step economy by skipping the separate operation for preparing the iodo‐functionalized chromone intermediate. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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10. Enhanced UV Nonlinear Optical Properties in Layered Germanous Phosphites through Functional Group Sequential Construction.
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Tian, Yao, Zeng, Wei, Dong, Xuehua, Huang, Ling, Zhou, Yuqiao, Zeng, Hongmei, Lin, Zhien, and Zou, Guohong
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FUNCTIONAL groups , *OPTICAL properties , *FREQUENCY changers , *PHOSPHITES , *COHERENCE (Optics) , *NONLINEAR optical spectroscopy - Abstract
This study pioneers a novel strategy for synthesizing solar‐blind ultraviolet (UV) nonlinear optical (NLO) crystals through functional groups sequential construction, effectively addressing the inherent trade‐offs among broad transmittance, enhanced second‐harmonic generation (SHG), and optimal birefringence. We have developed two innovative van der Waals layered germanous phosphites: GeHPO3, the first Ge(II)‐based oxide NLO crystal which exhibits a black phosphorus‐like structure, and K(GeHPO3)2Br, distinguished by its exceptional birefringence and graphene‐like structure. Significantly, GeHPO3 exhibits a remarkable array of NLO properties, including the highest SHG coefficient recorded among all NLO crystals for phase‐matching and generating 266 nm coherent light via quadruple frequency conversion. It delivers a potent SHG intensity, surpassing KH2PO4 (KDP) by 10.3 times at 1064 nm and β‐BaB2O4 by 1.3 times at 532 nm, complemented by a distinct UV absorption edge at 211 nm and moderate birefringence of 0.062 at 546 nm. Comprehensive theoretical analysis links these exceptional characteristics to the unique NLO‐active GeO34− units and the distinctive, highly ordered layered structures. Our findings deliver essential experimental insights into the development of Ge(II)‐based optoelectronic materials and present a strategic blueprint for engineering structure‐driven functional materials with customized properties. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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11. Synthesis and characterization of new highly fluorinated phosphoramidates bearing different alkylamino groups.
- Author
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Argoubi, Samar, Sanhoury, M. A., Zerough, I., Manoury, E., and Chehidi, I.
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NUCLEAR magnetic resonance spectroscopy , *PHOSPHORAMIDATES , *PHOSPHITES , *FLUOROALKYL compounds , *IODINE - Abstract
Seventeen new highly fluorinated phosphoramidates containing alkylamino moieties of the type (RFO)2P(O)NHR (R = CH2CH2CH3, (CH2)3CH3, (CH2)4-CH3, CH(CH3)2, C6H11, CH2CH2-C6H5, CH2-C6H5 or C6H5; RF = CH2CF3, CH2C2F5 or CH2CH2C6F13) were synthesized. These compounds were obtained through the reaction of primary amines with bis(polyfluoroalkyl)phosphites as phosphorylating agents, using molecular iodine as a mild catalyst and in the presence of H2O2.This method was chosen out of various literature common methods, which were thoroughly investigated using 31P NMR spectroscopy. In addition, the variation in reaction rates among different phosphites was studied and compared with previous research findings. The title phosphoramidates were fully characterized using multinuclear (1H,13C,31P, and 19F) NMR, IR, and HRMS techniques. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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12. Eco-friendly synthesis, antimicrobial activity, molecular docking and ADMET studies of novel α-aminophosphonates.
- Author
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Poreddy, Sumithra, Gundluru, Mohan, Sarva, Santhisudha, Pothuraju, Surendra, Bellala, Poojitha, Konidala, Kranthi Kumar, Yeguvapalli, Suneetha, and Cirandur, Suresh Reddy
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MOLECULAR docking , *ANTI-infective agents , *BINDING sites , *FUNCTIONAL groups , *PHOSPHITES - Abstract
An efficient one-pot Kabachnik-Fields reaction has been carried out for the synthesis of novel α-aminophosphonates under microwave irradiation and solvent-free conditions by 2-hydroxy-1-naphthaldehyde, aromatic amines and dialkyl phosphites using Hydroxyapatite nanoparticles (HAp NPs) as catalyst. The present new protocol is environmentally benign as it offers some interesting and promising features like solvent-free, low cost, safety, minimal waste, atom efficiency, easy work-up, short reaction time and possessing excellent functional group tolerance to structurally diverse derivatives. The title compounds were subjected to antimicrobial activity against bacterial and fungal strains by disc diffusion and MIC methods. Advanced computational tools were also employed to conduct molecular docking and toxicogenomic investigations on target compounds. Employing ensemble-docking approaches, the primary contenders were identified for their potential to bind to the active sites of GlcN-6-P synthase, with PDB IDs 2VF5 and 2POC acting as target receptors. ADMET studies revealed promising drug-like characteristics of these compounds. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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13. Monofluorophos–Metal Complexes: Ripe for Future Discoveries in Homogeneous Catalysis.
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Miles-Hobbs, Alexandra M., Pringle, Paul G., Woollins, J. Derek, and Good, Daniel
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HOMOGENEOUS catalysis , *KINETIC control , *HYDROFORMYLATION , *COORDINATE covalent bond , *OXIDATION states , *METAL complexes - Abstract
The discovery that cyclic (ArO)2PF can support Rh-catalysts for hydroformylation with significant advantages in tuning regioselectivity transformed the study of metal complexes of monofluorophos ligands from one of primarily academic interest to one with potentially important applications in catalysis. In this review, the syntheses of monofluorophosphites, (RO)2PF, and monofluorophosphines, R2PF, are discussed and the factors that control the kinetic stability of these ligands to hydrolysis and disproportionation are set out. A survey of the coordination chemistry of these two classes of monofluorophos ligands with d-block metals is presented, emphasising the bonding of the fluorophos to d-block metals, predominantly in low oxidation states. The application of monofluorophos ligands in homogeneous catalysis (especially hydroformylation and hydrocyanation) is discussed, and it is argued that there is great potential for monofluorophos complexes in future catalytic applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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14. Influence of the Gas Medium Composition on the Thermal Decomposition of Ammonium, Sodium, Potassium, and Calcium Hypophosphites.
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Vereshchagin, A. L., Minin, E. D., Bychin, N. V., and Morozova, E. A.
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HYPOPHOSPHITES , *POLYPHOSPHORIC acid , *THERMAL analysis , *MASS media influence , *POTASSIUM - Abstract
The key step of the thermal decomposition of hypophosphites is disproportionation determining the phase composition and morphology of the final products. The distinctive features of the thermal decomposition of hypophosphites are the formation of polyphosphoric acid from ammonium hypophosphite and of red phosphorus from the metal hypophosphites. The thermal decomposition of hypophosphites in air is accompanied by large heat release. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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15. Complexation with PdII and enantioselective allylic amination using new P*-monodentane bicyclic amidophosphite.
- Author
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Gavrilov, K. N., Chuchelkin, I. V., Trunina, V. M., Gavrilov, B. K., Firsin, I. D., Rud, E. S., Tafeenko, V. A., and Bermesheva, E. V.
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ALLYLIC amination , *PALLADIUM catalysts , *NUCLEAR magnetic resonance spectroscopy , *CHEMICAL synthesis , *X-ray diffraction - Abstract
A new representative of P*-monodentate bicyclic amidophosphite ligands of 2,6-dioxa-7-aza-1-phosphabicyclo[2.2.1]heptane series and its complex [Pd(allyl)(L)Cl] were obtained. Newly synthesized compounds were thoroughly characterized by 31P{1H}, 1H, and 13C{1H} NMR spectroscopy and 2D NMR experiments. The structure of the ligand was confirmed by X-ray diffraction analysis. Palladium catalysts derived from this chiral inductor provided up to 50% ee in asymmetric amination of (E)-1,3-diphenylallyl acetate with pyrrolidine. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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16. Mn(OAc)3 promoted cross-coupling reaction of disulfides with dialkyl phosphites.
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Wang, Wen-Juan, Sun, Jia, Wan, Jian-Xin, and Wang, Xi-Cun
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PHOSPHITES , *DISULFIDES - Abstract
A novel and facile method for the formation of C–S bonds via Mn(III) promoted cross-coupling reaction of disulfides with dialkyl phosphites under mild reaction conditions has been achieved. This strategy allows various dialkyl phosphites and disulfides to be transferred into the desired products in good to excellent yields. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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17. Cage‐Shaped Phosphites Having C3‐Symmetric Chiral Environment: Steric Control of Lewis Basicity and Application as Chiral Ligands in Rhodium‐Catalyzed Conjugate Additions.
- Author
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Liu, Xiao, Tomita, Kazuma, Konishi, Akihito, and Yasuda, Makoto
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LEWIS basicity , *CARBONYL compounds , *PHOSPHITES , *LIGANDS (Chemistry) , *RHODIUM catalysts , *LEWIS bases , *CHIRALITY of nuclear particles - Abstract
Designing chiral ligands with an axial symmetry higher than C2‐rotational symmetry is one of the most crucial approaches to improving enantioselectivity in asymmetric synthesis. Herein, C3‐symmetric chiral cage‐shaped phosphites are reported. Their Lewis basicity and chiral environment are precisely controlled by the tethered group. The cage‐shaped phosphites successfully worked as chiral ligands in Rh‐catalyzed asymmetric conjugate additions, realizing acceptable yields with excellent enantioselectivity, and were used to synthesize a pharmacologically important molecule. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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18. The diversity and evolution of microbial dissimilatory phosphite oxidation
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Ewens, Sophia D, Gomberg, Alexa FS, Barnum, Tyler P, Borton, Mikayla A, Carlson, Hans K, Wrighton, Kelly C, and Coates, John D
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Microbiology ,Biological Sciences ,Genetics ,Anaerobiosis ,Bacteria ,Bacterial Proteins ,Biodiversity ,Carbon Dioxide ,Chemoautotrophic Growth ,Energy Metabolism ,Evolution ,Molecular ,Genetic Variation ,Genome ,Bacterial ,Microbiota ,Oxidation-Reduction ,Phosphites ,Phylogeny ,Wastewater ,CO2 fixation ,phosphite ,glycine reductive pathway ,Desulfotignum ,Phosphitivorax - Abstract
Phosphite is the most energetically favorable chemotrophic electron donor known, with a half-cell potential (Eo') of -650 mV for the PO43-/PO33- couple. Since the discovery of microbial dissimilatory phosphite oxidation (DPO) in 2000, the environmental distribution, evolution, and diversity of DPO microorganisms (DPOMs) have remained enigmatic, as only two species have been identified. Here, metagenomic sequencing of phosphite-enriched microbial communities enabled the genome reconstruction and metabolic characterization of 21 additional DPOMs. These DPOMs spanned six classes of bacteria, including the Negativicutes, Desulfotomaculia, Synergistia, Syntrophia, Desulfobacteria, and Desulfomonilia_A Comparing the DPO genes from the genomes of enriched organisms with over 17,000 publicly available metagenomes revealed the global existence of this metabolism in diverse anoxic environments, including wastewaters, sediments, and subsurface aquifers. Despite their newfound environmental and taxonomic diversity, metagenomic analyses suggested that the typical DPOM is a chemolithoautotroph that occupies low-oxygen environments and specializes in phosphite oxidation coupled to CO2 reduction. Phylogenetic analyses indicated that the DPO genes form a highly conserved cluster that likely has ancient origins predating the split of monoderm and diderm bacteria. By coupling microbial cultivation strategies with metagenomics, these studies highlighted the unsampled metabolic versatility latent in microbial communities. We have uncovered the unexpected prevalence, diversity, biochemical specialization, and ancient origins of a unique metabolism central to the redox cycling of phosphorus, a primary nutrient on Earth.
- Published
- 2021
19. Regioselective Rhodium‐Catalyzed 1,2‐Hydroboration of Pyridines and Quinolines Enabled by the Tris(8‐quinolinyl)phosphite Ligand**.
- Author
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Chacón‐Terán, Miguel A., Landaeta, Vanessa R., Wolf, Robert, and Rodríguez‐Lugo, Rafael E.
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MOLECULAR structure , *TURNOVER frequency (Catalysis) , *HYDROBORATION , *X-ray diffraction , *CHELATES , *QUINOLINE - Abstract
A Rh(I) complex [κ2(P,N)‐{P(Oquin)3}RhCl(PPh3)] (1) bearing the P,N ligand tris(8‐quinolinyl)phosphite, P(Oquin)3, has been synthesized and structurally characterized. The molecular structure of complex 1 shows that P(Oquin)3 acts as a bidentate P,N chelate ligand. Reactivity studies of 1 reveal that the triphenylphosphine ligand can be replaced by Pcy3 or removed upon oxidation with concomitant coordination of a second 8‐quinolyl unit of P(Oquin)3. In addition, the Rh(III) complex [RhCl2{OP(Oquin)2}] (3), resulting from treating 1 with either wet CDCl3 or, sequentially, with HCl and water, was identified by X‐ray diffraction analysis. Complex 1 catalyzes the 1,2‐regioselective hydroboration of pyridines and quinolines, affording N‐boryl‐1,2‐dihydropyridines (1,2‐BDHP) and N‐boryl‐1,2‐hydroquinolines (1,2‐BDHQ) in high yield (up to >95 %) with turnover numbers (TONs) of up to 130. The system tolerates a variety of substrates of different electronic and steric nature. In comparison with other transition‐metal‐based hydroboration catalysts, this system is efficient at a low catalyst loading without the requirement of base or other additives. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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20. Asymmetric Organocatalyzed Phospha‐Michael Addition for the Direct Synthesis of Biologically Active Chromenylphosphonates.
- Author
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Marqués‐López, Eugenia, Sonsona, Isaac G., Garcés‐Marín, Miryam, Gimeno, M. Concepción, and Herrera, Raquel P.
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ASYMMETRIC synthesis , *BIOACTIVE compounds , *NUCLEOPHILES , *PHOSPHITES - Abstract
The potential of phosphites as nucleophiles for the asymmetric synthesis of chiral chromene derivatives has been overlooked in the literature. Herein, we report a promising approach via asymmetric organocatalyzed phospha‐Michael addition to iminochromenes, using a bifunctional squaramide, which gives access to chromenylphosphonates, an interesting family of bioactive compounds. Our optimized protocol provides very good reactivity, affording yields of up to 95% and with chiral products exhibiting an enantiomeric excess of up to 98%. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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21. A series of novel phosphites/phosphates with deep-ultraviolet cut-off edges from 0D polar to 3D non-polar architectures.
- Author
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Hao, Yucheng, Zhang, Yang, Zhang, Yuying, Fu, Zixiang, Heng, Chunyang, Li, Junjie, You, Jiatian, Hu, Kunhong, Lin, Yuan, and Li, Haijian
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PHOSPHITES , *MOLECULAR structure , *SECOND harmonic generation , *REFLECTANCE spectroscopy , *INFRARED spectroscopy , *TETRAHEDRA - Abstract
Four new phosphites/phosphates, namely Al[P2O3(OH)3](H2O), Al[(HPO3)(OH)(H2O)], Ca[HPO3] and Al3P6O19.5, were designed and synthesized by low temperature flux methods. They crystallized in P63mc, P1¯, P43212, and P63/m space groups, respectively. The basic units of Al[P2O3(OH)3](H2O), Al[(HPO3)(OH)(H2O)] and Ca[HPO3] are composed of [PO3]3− or/and [AlO6]9− groups, whereas the structure of Al3P6O19.5 is built from [PO4]3− tetrahedra and [AlO6]9− octahedra. The structure of Al[P2O3(OH)3](H2O) features a two-dimensional (2D) layered motif of Al[P2O3(OH)3]. Meanwhile, Al[(HPO3)(OH)(H2O)] has high porosity and relatively large channels, and has an excellent molecular sieve structure. Both Al[P2O3(OH)3](H2O) and Al[(HPO3)(OH)(H2O)] display deep ultraviolet (UV) cut-off edges of ∼195 nm and ∼193 nm. The three-dimensional (3D) structure of Al3P6O19.5 is formed by [Al2O9] dimers connected with six PO4 tetrahedra, and one PO4 tetrahedron linked three [Al2O9] dimers alternately. Importantly, Ca[HPO3] shows a moderate second harmonic generation (SHG) effect with a short UV cut-off edge of ∼192 nm in the deep-UV region. The syntheses and topological structures of Al[P2O3(OH)3](H2O), Al[(HPO3)(OH)(H2O)], Ca[HPO3] and Al3P6O19.5, together with some related properties, such as nonlinear optical (NLO) properties, elemental analysis, thermal stability, infrared spectroscopy, Raman spectroscopy and UV-vis diffuse reflectance spectroscopy, are also discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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22. The Last Decade of Optically Active α-Aminophosphonates.
- Author
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Varga, Petra R. and Keglevich, György
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OXO compounds , *HYDROGENATION , *ASYMMETRIC synthesis , *PHOSPHITES , *IMINES , *OPTICAL rotation - Abstract
α-Aminophosphonates and related compounds are important due to their real and potential biological activity. α-Aminophosphonates may be prepared by the Kabachnik–Fields condensation of oxo compounds, amines and dialkyl phosphites, or by the aza-Pudovik addition of the same P-reagents to imines. In this review, the methods that allow for the synthesis of α-aminophosphonates with optical activity are surveyed. On the one hand, optically active catalysts or ligands may induce enantioselectivity during the Kabachnik–Fields reaction. On the other hand, asymmetric catalysis during the aza-Pudovik reaction, or hydrogenations of iminophosphonates, may prove to be a useful tool. Lastly yet importantly, it is possible to start from optically active reagents that may be associated with diastereoselectivity. The "green" aspects of the different syntheses are also considered. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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23. A Study of the Bisphosphonic Derivatives from the Pudovik Reaction of Dialkyl α-Oxophosphonates and >P(O)H Reagents: X-ray Structure and Bioactivity.
- Author
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Szalai, Zsuzsanna, Tóth, Boldizsár, Szabó, Rita Oláhné, Bősze, Szilvia, Karaghiosoff, Konstantin, Czugler, Mátyás, Drahos, László, and Keglevich, György
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X-ray crystallography , *X-rays , *CELL culture , *DIETHYLAMINE , *PHOSPHITES - Abstract
New hydroxy-methylenebisphosphonic derivatives were prepared with different P-functions. The outcome of the reaction of α-oxophosphonates (YC(O)P(O)(OR)2) and dialkyl phosphites or diarylphosphine oxides depended on the Y substituent of the oxo-compound, the nature of the P-reagent and the amount of the diethylamine catalyst. Starting from dimethyl α-oxoethylphosphonate, in the presence of 5% of diethylamine, the corresponding Pudovik adduct was the single product. While using 40% of the catalyst, the rearranged species with the >P(O)–O–CH–P(O)< skeleton was the exclusive component. A similar reaction of α-oxobenzylphosphonate followed the rearrangement protocol. X-ray crystallography revealed not only the spatial structures of the three products, but also an intricate pattern evolving from the interplay of slight chemical differences, solvent inclusion and disorder as well as H-bridge patterns, which invite further investigation. In vitro activity of the compounds was assessed on different tumor cell cultures using end-point-type cell tetrazolium-based measurements. These structure–activity studies revealed a cytostatic effect for four rearranged derivatives containing aromatic units. One of them had a pronounced effect on MDA-MB 231 and Ebc-1 cells, showing IC50 = 37.8 and 25.9 µM, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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24. A New Synthesis of Trimethylsilyl Esters of Phosphorus(III) Acids.
- Author
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Morgalyuk, V. P., Strelkova, T. S., Takazova, R. U., Buyanovskaya, A. G., and Brel, V. K.
- Subjects
- *
DIETHYLAMINE , *PHOSPHORUS , *ACIDS , *ESTERS , *PHOSPHITES , *SOLVENTS - Abstract
Trimethylsilyl esters of P(III) acids were synthesized in high yields (89–94%) by the reaction of hydrophosphoryl compounds with hexamethyldisilazane at 20°C in the presence of ZnSO4 and diethylamine. The reaction is complete in 4 h, it does not require specially prepared solvents or an inert atmosphere, and can be proposed as a new synthetically useful and easy-to-perform method for the synthesis of trimethylsilyl esters of P(III) acids. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
25. Electrochemically induced efficient, simple, non-catalytic synthesis of β-phosphonomalonates via multicomponent reaction.
- Author
-
Singh, Vinay K., Chandra, Phool, Srivastav, Shekhar, and Singh, Renu
- Subjects
- *
MALONATES , *MALONONITRILE , *ELECTROCHEMISTRY , *NUCLEOPHILIC addition (Chemistry) , *PHOSPHITES - Abstract
Electrochemically induced efficient and economical method has been developed for synthesis of β-phosphono malononitriles via condensation of various aldehyde, malononitrile and phosphite esters at room temperature. The present protocol highlights cost efficient, one pot, easy work-up and environmentally benign process. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
26. Catalyst‐ and Solvent‐Free Room Temperature Synthesis of α‐Aminophosphonates: Green Accomplishment of the Kabachnik–Fields Reaction.
- Author
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Gábor, Dóra, Pollák, Patrik, Volk, Balázs, Dancsó, András, Simig, Gyula, and Milen, Mátyás
- Subjects
- *
CARBONYL compounds , *RATE coefficients (Chemistry) , *TEMPERATURE , *ANILINE , *PHOSPHITES - Abstract
A catalyst‐ and solvent‐free room temperature method has been elaborated for the three‐component (carbonyl compounds, primary or secondary amines and phosphites) Kabachnik–Fields synthesis of α‐aminophosphonates. First, we have studied some parameters that potentially influence the course of the reaction using benzaldehyde, aniline and diethyl phosphite. In order to extend the reaction under the new reaction conditions, we then carried out 3 series of experiments always varying one of the three reagents. In general, with a few exceptions, good yields were obtained, although in some cases long reaction times were required. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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27. Insertion of Chemical Handles into the Backbone of DNA during Solid‐Phase Synthesis by Oxidative Coupling of Amines to Phosphites.
- Author
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Hansen, Rikke A., Märcher, Anders, Pedersen, Kristian Nørgaard, and Gothelf, Kurt V.
- Subjects
- *
SOLID-phase synthesis , *OXIDATIVE coupling , *OLIGONUCLEOTIDE synthesis , *PHOSPHITES , *OLIGONUCLEOTIDES , *AMINES , *SECONDARY amines , *DNA insertion elements - Abstract
Conjugation of molecules or proteins to oligonucleotides can improve their functional and therapeutic capacity. However, such modifications are often limited to the 5′ and 3′ end of oligonucleotides. Herein, we report the development of an inexpensive and simple method that allows for the insertion of chemical handles into the backbone of oligonucleotides. This method is compatible with standardized automated solid‐phase oligonucleotide synthesis, and relies on formation of phosphoramidates. A unique phosphoramidite is incorporated into a growing oligonucleotide, and oxidized to the desired phosphoramidate using iodine and an amine of choice. Azides, alkynes, amines, and alkanes have been linked to oligonucleotides via internally positioned phosphoramidates with oxidative coupling yields above 80 %. We show the design of phosphoramidates from secondary amines that specifically hydrolyze to the phosphate only at decreased pH. Finally, we show the synthesis of an antibody‐DNA conjugate, where the oligonucleotide can be selectively released in a pH 5.5 buffer. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
28. Phosphites for the management of tomato bacterial canker and stem rot.
- Author
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Coskun, Tolgahan Ahmet and Horuz, Sumer
- Subjects
- *
PHOSPHITES , *FUNGICIDES , *TOMATOES , *BACTERIAL diseases , *DISEASE management , *ERWINIA , *CHLOROPHYLL - Abstract
Tomato bacterial canker and stem rot are two of the most devastating bacterial diseases of tomatoes worldwide. Tomato cultivars that are resistant to these diseases are not available; thus, alternative control strategies are needed. In this study, the foliar spray effect of five individual phosphites and a fungicide on tomato bacterial canker and stem rot disease development, chlorophyll concentration, dry weight and stem diameter was investigated under controlled greenhouse conditions in two pot experiments. Phosphites inhibited the growth of Clavibacter michiganensis subsp. michiganensis (Cmm) between 50 and 74%, and raised the chlorophyll concentration estimated by SPAD measurements of tomato leaves up to 30% in phosphite sprayed plants. Likewise, phosphites reduced Pectobacterium carotovorum subsp. carotovorum (Pcc) development among 31% and 82% and induced an relative increases in chlorophyll concentration compared to control. Since the increase in dry weight (up to 15%) and stem diameter (up to 3%) of tomato plants varied in the first experiment, no increase observed for the second experiment. Additionally, no statistically significant differences (P ≤ 0.05) were figured out in dry weight and stem diameter of tomato plants compared to positive controls in response to both diseases. These results indicated that phosphites could be included effectively in tomato bacterial canker and stem rot disease management. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
29. Synthesis of New Symmetrical Diamidophosphates Based on meta-Phenylenediamine under Microwave Irradiation.
- Author
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Kuandykova, A. B., Dzhiembaev, B. Zh., Burilov, A. R., Akylbekov, N. I., Chugunova, E. A., Dobrynin, A. B., and Abyzbekova, G. M.
- Subjects
- *
MICROWAVES , *IRRADIATION , *ELEMENTAL analysis , *MASS spectrometry , *SINGLE crystals , *PHENYLENEDIAMINES - Abstract
A new series of diphosphorylated amidophosphates was obtained as a result of the reaction of meta-phenylenediamine with dialkyl phosphites in the presence of CCl4 and triethylamine (Atherton–Todd reaction) under microwave irradiation. Structure of all the obtained amidophosphates was established on the basis of 31P, 1H, 13C NMR, IR spectroscopy and mass spectrometry methods, as well as single crystal X-ray diffraction and elemental analysis data. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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30. Spectroscopic investigation of KBa2(PO3)5:Mn4+ activated glasses for plant cultivation applications
- Author
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Prashant N. Parale, Abhijeet R. Kadam, K.V. Dabre, and S.J. Dhoble
- Subjects
Far red emission ,Melt quenching ,Plant cultivation ,Phosphites ,Luminescent glasses ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Mn4+ is an impressive activator and sensitizer for luminescent material, which has been comprehensively investigated during the recent decades. In the present work, we give an account of the luminescence properties of Mn4+ activated KBa(PO3)5 glasses are successfully synthesized by using Melt quenching technique. SEM investigation confirms the proposed phosphite glass's morphological behaviour. A photoluminescence research showed that the proposed phosphor's emission peak was positioned in the far red emission area after being excited in the blue region. There are numerous indications that the peaks seen in the 650–750 nm region are helpful for growing plants. Therefore, the suggested glass sample is a promising contender for the use of cultivating far-red emitting plants.
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- 2023
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31. P*,S-Bidentate diamidophosphite based on 3-(phenylthiomethyl)phenol.
- Author
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Gavrilov, K. N., Chuchelkin, I. V., Gavrilov, V. K., Trunina, V. M., Firsin, I. D., Zheglov, S. V., Bityak, Ya. P., Fedorov, D. A., Zimarev, V. S., and Goulioukina, N. S.
- Subjects
- *
PHENOL , *PALLADIUM catalysts , *ETHYL acetate , *ALKYLATION , *ALLYLIC alkylation , *PYRROLIDINE , *PALLADIUM compounds - Abstract
A new P*,S-bidentate diamidophosphite ligand 1, containing a stereogenic phosphorus atom as a part of the 1,3,2-diazaphospholidine ring, was synthesized based on 3-(phenylthiomethyl)phenol. Palladium catalysts on its basis demonstrated a high enantioselectivity in the allylic alkylation of (E)-1,3-diphenylallyl acetate with dimethyl malonate (76% ee), the amination with pyrrolidine (74% ee), and the alkylation of cinnamyl acetate with ethyl 2-oxocyclohexanecarboxylate (83% ee). The reaction of ligand 1 with [Pd(allyl)Cl]2 in the presence of AgBF4 afforded a mixture of cationic palladium complexes: chelate [Pd(allyl)1]BF4 and head-to-head binuclear complex [Pd(allyl)1]2(BF4)2. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
32. First P*-chiral bicyclophosphite-type ligands.
- Author
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Gavrilov, V. K., Chuchelkin, I. V., Zheglov, S. V., Gavrilov, K. N., Firsin, I. D., and Borisova, N. E.
- Subjects
- *
LIGANDS (Chemistry) , *ATOMS - Abstract
New readily accessible aminodiol and diaminoalcohol were obtained using simple condensation and reduction reactions. On their basis, earlier unknown ligands of bicyclophosphite nature with asymmetric phosphorus atoms were synthesized. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
33. Facile reduction of phosphine oxides and H-phosphonates by ditetrelenes.
- Author
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Belcina, Maissa P., Farhadpour, Bahareh, Tashkandi, Nada Y., Henry, Andrew T., Bourque, Jeremy L., and Baines, Kim M.
- Abstract
The addition of secondary phosphine oxides to tetramesityldisilene and tetramesityldigermene results in the mild, partial reduction of the P(V) centre of the organophosphorus oxide to P(III) to yield disilyl and digermyl phosphinite derivatives and illustrates the potential of ditetrelenes to serve as mild reducing agents under ambient conditions. An analogous reaction happens with H-phosphonates. Mechanistic experiments, including deuterium labelling, kinetic isotope effect, and variable time normalization analysis experiments, reveal that the 1,3-PH addition likely proceeds through a stepwise reaction pathway with the organophosphorus oxide acting as the nucleophile toward the ditetrelene. Furthermore, a facile exchange between the R2PO moiety of the digermylphosphinite and the R2PO moiety of phosphine oxides was discovered and likely proceeds through a direct substitution mechanism. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
34. Inorganic Fungicides (Phosphites) Instead of Organic Fungicides in Winter Wheat—Consequences for Nitrogen Fertilizer Productivity.
- Author
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Grzebisz, Witold, Łączny, Szymon, Szczepaniak, Witold, and Potarzycki, Jarosław
- Subjects
- *
WINTER wheat , *FUNGICIDES , *PHOSPHITES , *NITROGEN fertilizers , *GROWING season , *GRAIN yields , *PLANT protection - Abstract
Substitution of organic with inorganic fungicides (phosphites, Phi) does not change the efficiency of fertilizer nitrogen (Nf) in winter wheat. This hypothesis was tested in the 2016/2017 and 2017/2018 growing seasons. A two-factorial experiment with three phosphite variants (Cu–Phi, Mg–Phi, and Cu/Mg) and six plant protection methods (fungicides + Phi ⟶ reduced fungicide frequency + phosphite ⟶ phosphite). Grain yield decreased with increasing frequency of phosphites instead of fungicides. The decrease in yields was 3.6 t ha−1 in the favorable 2016/2017 and 1.1 t ha−1 in the dry 2017/2018. The primary reason for yield decrease in a given growing season was increased wheat infestation by pathogens. The direct cause was disturbances in the nitrogen status of wheat after flowering on treatments with a predominance of phosphites. The thousand grain weight (TGW) responded negatively to reduced fungicide application frequency. The critical stage in the assessment of pathogen pressure on wheat was the medium milk phase (BBCH 75). At this stage, indices of SPAD and leaf greenness together with indices of wheat infestation with pathogens allowed for a reliable prediction of both TGW and grain yield. It can be concluded that phosphites do not substitute organic fungicides in limiting pathogen pressure in winter wheat. Moreover, increased pressure of pathogens significantly reduces Nf productivity. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
35. Bridging micro and macro scale: Deciphering the role of phosphite ligand configuration in propene hydroformylation via microkinetic and vapor-liquid equilibrium modeling.
- Author
-
Zhang, Minhua, Mo, Hongkun, and Chen, Yifei
- Subjects
- *
LIGANDS (Chemistry) , *HYDROFORMYLATION , *PHOSPHITES , *VAPOR-liquid equilibrium , *DENSITY functional theory - Abstract
• Explored the catalytic cycle of hydroformylation on four phosphite P-ligands. • Fig. out the catalytic performance with DFT calculations. • Linking micro and macro scale based on reactor modeling with MKM and VLE. • Deconstruct the joint impact of ligands' electrons and spatial effects. • Proposed how steric hindrance influence catalyst activity and selectivity. In this work, the effects of phosphite ligand structural modifications on the Rhodium-catalyzed hydroformylation of propene were elucidated by density functional theory (DFT) calculations and reactor model with microkinetic modelling (MKM) and gas-liquid equilibrium modeling (VLE). How the unique structural features of four phosphite ligands, namely BiPhePhos, 2,2'-Biphenylylene phosphite, BinaPhtPhos, and P(OPh) 3 , influence the catalytic activity and selectivity toward linear aldehydes were analyzed. The results revealed that BiPhePhos, which includes methoxy and tert-butyl groups, significantly enhances catalytic activity and selectivity. In contrast, 2,2'-Biphenylylene and BinaPhtPhos phosphite lack these groups and notably decrease the selectivity of linear aldehyde because of the lower Mayer valences of Rhodium. Additionally, we utilized interaction region indicator (IRI) analysis to compare and analyze the spatial steric hindrance distribution of the bidentate phosphite BiPhePhos and the monodentate ligand PPh 3. The results revealed how the spatial steric hindrance distribution of the BiPhePhos structure with a high linear-to-branched aldehyde (l/b) ratio affects the rotation of the alkene in the alkene insertion reaction, elucidating the intrinsic reason why the propene hydroformylation reaction pathway tends to follow the linear aldehyde pathway. These results reveal the critical effects of ligand architecture in determining the efficiency and yield of the hydroformylation process. The influence of electronic properties and steric hindrance distributions of phosphite P-ligands on propene hydroformylation: A combination of DFT, MKM, and VLE study. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. Synthesis of N-Glycolylneuraminic Acid (Neu5Gc) and Its Glycosides
- Author
-
Kooner, Anoopjit Singh, Yu, Hai, and Chen, Xi
- Subjects
Biochemistry and Cell Biology ,Biological Sciences ,Nutrition ,Chemistry Techniques ,Synthetic ,Glycosides ,Molecular Structure ,Neuraminic Acids ,Oligosaccharides ,Phosphites ,sialic acid ,sialoside ,Neu5Gc ,chemical synthesis ,chemoenzymatic synthesis ,Immunology ,Medical Microbiology ,Biochemistry and cell biology ,Genetics - Abstract
Sialic acids constitute a family of negatively charged structurally diverse monosaccharides that are commonly presented on the termini of glycans in higher animals and some microorganisms. In addition to N-acetylneuraminic acid (Neu5Ac), N-glycolyl neuraminic acid (Neu5Gc) is among the most common sialic acid forms in nature. Nevertheless, unlike most animals, human cells loss the ability to synthesize Neu5Gc although Neu5Gc-containing glycoconjugates have been found on human cancer cells and in various human tissues due to dietary incorporation of Neu5Gc. Some pathogenic bacteria also produce Neu5Ac and the corresponding glycoconjugates but Neu5Gc-producing bacteria have yet to be found. In addition to Neu5Gc, more than 20 Neu5Gc derivatives have been found in non-human vertebrates. To explore the biological roles of Neu5Gc and its naturally occurring derivatives as well as the corresponding glycans and glycoconjugates, various chemical and enzymatic synthetic methods have been developed to obtain a vast array of glycosides containing Neu5Gc and/or its derivatives. Here we provide an overview on various synthetic methods that have been developed. Among these, the application of highly efficient one-pot multienzyme (OPME) sialylation systems in synthesizing compounds containing Neu5Gc and derivatives has been proven as a powerful strategy.
- Published
- 2019
37. Catalyst-Free Synthesis of Phosphorothioates via P–S Coupling -Reaction of Dialkyl Phosphites with Thiols.
- Author
-
Kaboudin, Babak, Daliri, Payam, Esfandiari, Hesam, and Kazemi, Foad
- Subjects
- *
THIOPHOSPHATES , *PHOSPHITES , *DIMETHYL sulfoxide , *OXIDIZING agents , *SOLVENTS , *SONOGASHIRA reaction , *DISULFIDES - Abstract
A catalyst-free synthesis of phosphorothioates via a P–S cross-coupling reaction of thiols with dialkyl phosphites has been studied. With presented method, various phosphorothioates were obtained by the reaction of thiols with H-dialkyl phosphites in the presence of DMSO as both solvent and oxidant under transition-metal-free conditions. Mechanistic studies showed that the reaction proceeds with formation of a known disulfide intermediate via the oxidation of thiols in the presence of DMSO. Nucleophilic substitution of dialkyl phosphite with the disulfide intermediate gave phosphorothioate. The presented method is a convenient process for the synthesis of phosphorothioates under catalyst-free conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. Organophosphites: An Addition to the Arsenal of Organocatalysts.
- Author
-
Baral, Nilofar, Rani, Soniya, Saikia, Pinku, and Maity, Pradip
- Subjects
- *
ORGANOCATALYSIS , *ARSENALS , *PHOSPHITES , *UMPOLUNG , *CATALYSIS , *CATALYSTS - Abstract
Organophosphites are nucleophilic in nature and can act as a good leaving group owing to the stability of the phosphite anion. This dual reactivity makes them good candidates for nucleophilic organocatalysis. However, phosphites were introduced only in 2004 as the umpolung catalyst for acylsilane substrates utilizing sequential Brook rearrangements. Very recently, phosphites have been reported to catalyze aza‐rearrangements and radical reactions. In this review, we discuss the reactivity parameters to understand its lack of use, as well as the potential for catalysis. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
39. EXTRACTION PROPERTIES OF SYNTHESIZED FLUORINATED ORGANOPHOSPHORUS COMPOUNDS.
- Author
-
Bishimbayeva, G. K., Nalibayeva, A. M., Saidullayeva, S. A., Zhangabayeva, A. K., Bold, A., Zhumabayeva, D. S., Abdikalykov, Y. N., and Panova, E. N.
- Subjects
- *
URANIUM , *ORGANOPHOSPHORUS compounds , *SULFURIC acid , *URANIUM oxides , *PHOSPHORUS compounds , *PHOSPHITES , *URANIUM compounds - Abstract
This work presents the results of studies of extraction properties in relation to the uranium of bis(2,2,2-trifluoroethyl)diallylamido phosphite, bis(2,2,2-trifluoroethyl)dimethylamido phosphite, and bis(N, Ndialamido) isopropyl phosphite synthesized by us earlier. Tests were carried out in a factory laboratory, as the initial solutions used nitrate solution prepared from uranium oxide (CU = 10.30 g/dm3, CHNO3 = 56.40 g/dm3) and uranium sulfate solution prepared from the chemical concentrate of natural uranium and deoxidized with sulfuric acid (CU = 10.60 g/dm3, CH2SO4 = 25.10 g/dm3). It was proved that the synthesized acyclic amido phosphites can effectively extract uranium from these technological solutions with a proper selection of technological parameters, and the degree of uranium extraction may vary from 34.43 to 95.94%. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
40. Determination of the efficacies of different phosphites in the management of tomato bacterial speck disease caused by Pseudomonas syringae pv. tomato.
- Author
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HAJİ NOUR, Saad Mohamed and HORUZ, Sümer
- Subjects
PHOSPHITES ,PSEUDOMONAS ,PATHOGENIC microorganisms ,PREVENTIVE medicine ,BACTERIAL diseases - Abstract
Copyright of Mustafa Kemal University Journal of Agricultural Sciences / Mustafa Kemal Üniversitesi Tarım Bilimleri Dergisi is the property of Mustafa Kemal University, Faculty of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2023
- Full Text
- View/download PDF
41. Bismuth‐catalyzed N‐Arylation of 2‐Aminobenzimidazole and Phosphorylation of Substituted Coumarins via C−H functionalization.
- Author
-
Aamir Bin Riyaz, M. and Swu, T.
- Subjects
- *
COUMARINS , *PHOSPHORYLATION , *CATALYTIC activity , *COUMARIN derivatives , *PHOSPHITES - Abstract
This work describes BiCl3's catalytic activity in synthesizing N‐arylbenzimidazole and the phosphorylation of substituted coumarins with alkyl and aryl phosphites. This framework is utilized to synthesize a variety of 2‐aminobenzimidazole and coumarin derivatives in moderate to high yields under mild reaction conditions. The catalyst employed is highly productive, less hazardous, and inexpensive, making it desirable economically and environmentally. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
42. Effect of Organic Cation on Optical Properties of [A]Mn(H 2 POO) 3 Hybrid Perovskites.
- Author
-
Stefańska, Dagmara
- Subjects
- *
PEROVSKITE , *OPTICAL properties , *BAND gaps , *CATIONS , *HYPOPHOSPHITES , *DAYLIGHT , *METAL-insulator transitions - Abstract
Hybrid organic–inorganic compounds crystallizing in a three-dimensional (3D) perovskite-type architecture have attracted considerable attention due to their multifunctional properties. One of the most intriguing groups is perovskites with hypophosphite linkers. Herein, the optical properties of six hybrid hypophosphite perovskites containing manganese ions are presented. The band gaps of these compounds, as well as the luminescence properties of the octahedrally coordinated Mn2+ ions associated with the 4T1g(G) → 6A1g(S) transition are shown to be dependent on the organic cation type and Goldschmidt tolerance factor. Thus, a correlation between essential structural features of Mn-based hybrid hypophosphites and their optical properties was observed. Additionally, the broad infrared luminescence of the studied compounds was examined for potential application in an indoor lighting system for plant growth. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
43. How Do Positions of Phosphito Units on a Calix[4]Arene Platform Affect the Enantioselectivity of a Catalytic Reaction?
- Author
-
Hkiri, Shaima and Sémeril, David
- Subjects
- *
RHODIUM , *AROMATIC compounds , *PHOSPHITES , *HYDROGENATION , *ESTERS - Abstract
Three chiral diphosphites, (S,S)-5,17-bis(1,1′-binaphthyl-2,2′-dioxyphosphanyloxy)-25,26,27,28-tetrapropyloxycalix[4]arene (1), (S,S)-5,11,17,23-tetra-tert-butyl-25,27-dipropoxy-26,28-bis(1,1′-binaphthyl-2,2′-dioxyphosphanyloxy)calix[4]arene (2) and (S,S)-5,11,17,23-tetra-tert-butyl-25,26-dipropoxy-27,28-bis(1,1′-binaphthyl-2,2′-dioxyphosphanyloxy)calix[4]arene (3), based on conical calix[4]arene were investigated in the rhodium-catalyzed asymmetric hydrogenation of α-dehydroamino esters. High conversions were observed after 24 h under 5 bar of hydrogen whatever the employed diphosphite, and the chiral induction increases in the order 1 < 3 < 2. This may be due to the presence of the calix[4]arene moiety, which by its presence modifies the second coordination sphere of the catalytic center. The larger steric hindrance around the rhodium atom leads to the higher enantiomeric excess. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
44. Synthesis of Chiral 1,4,2-Oxazaphosphorinanes Bearing Pyridyl Substituents.
- Author
-
Zinnatullin, R. G., Badeeva, E. K., Nikitina, K. A., Ivshin, K. A., Kataeva, O. N., and Metlushka, K. E.
- Subjects
- *
CHIRAL centers , *CATALYTIC activity , *DEALKYLATION , *IMINES , *PHOSPHITES , *FRIEDEL-Crafts reaction , *DIASTEREOISOMERS - Abstract
A series of 1,4,2-oxazaphosphorinanes was synthesized by the three-component reaction of chiral pyridylcontaining imines with trialkyl phosphites and monochloroacetic acid, followed by dealkylation of the P(O)OAlk-fragments of intermediates. It was established that the major diastereomers of the obtained heterocycles have the same configuration at both chiral centers. The synthesized 1,4,2-oxazaphosphorinanes show catalytic activity in the Friedel–Crafts reaction. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
45. Phosphorylation of 2-Aryl Quinoxaline Derivatives via C-H/P-H Cross Coupling under Transition-Metal-Free Conditions.
- Author
-
Karimi-Nami, Rahman, Adib, Mehdi, Heydari, Forouzan, Rajai-Daryasarei, Saeideh, and Karakaya, Idris
- Subjects
- *
QUINOXALINES , *PHOSPHONATE derivatives , *HETEROCYCLIC compounds , *PHOSPHITES , *PHOSPHONATES , *OXIDIZING agents - Abstract
In this study, we have developed an efficient protocol for synthesis of phosphorus-substituted heterocycles through reaction between 2-Aryl quinoxalines and dialkyl phosphites under transition-metal-free conditions. Here, K2S2O8 has been used as the sole oxidant for the facile synthesis of phosphorus substituted derivates. A variety of heteroaryl phosphonate derivatives have been synthesized under optimized conditions in good to excellent yields with this facile and environment friendly protocol. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
46. Controlled and Accelerated Hydrolysis of Polylactide (PLA) through Pentaerythritol Phosphites with Acid Scavengers.
- Author
-
Polidar, Matthias, Metzsch-Zilligen, Elke, and Pfaendner, Rudolf
- Subjects
- *
POLYLACTIC acid , *PENTAERYTHRITOL , *PHOSPHITES , *HYDROLYSIS , *POLYESTERS , *LACTIC acid , *BIODEGRADABLE plastics , *PLASTIC marine debris - Abstract
This study provides insight into the accelerated hydrolysis of polyester PLA through the addition of phosphites based on pentaerythritol. To control hydrolysis and ensure processing stability, different types of phosphites and combinations of phosphites with acid scavengers were studied. Therefore, commercially available PLA was compounded with selected additives on a twin-screw extruder, and hydrolysis experiments were performed at 23 °C, 35 °C and 58 °C in deionized water. Hydrolysis of PLA was evaluated by the melt volume rate (MVR) and size-exclusion chromatography (SEC). For example, after 4 days of water storage at 58 °C, the number average molecular weight of the PLA comparison sample was reduced by 31.3%, whereas PLA compounded with 0.8% phosphite P1 had a 57.7% lower molecular weight. The results are in good agreement with the expected and tested stability against hydrolysis of the investigated phosphite structures. 31P-NMR spectroscopy was utilized to elucidate the hydrolysis of phosphites in the presence of lactic acid. With the addition of phosphites based on pentaerythritol, the hydrolysis rate can be enhanced, and faster biodegradation behavior of biodegradable polyesters is expected. Accelerated biodegradation is beneficial for reducing the residence time of polymers in composting facilities or during home composting and as litter or microplastic residues. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
47. Visible‐Light Mediated Arbuzov‐Like Reaction with Thiophenols.
- Author
-
Rahaman, Rajjakfur, Nair, Akshay M., and Volla, Chandra M. R.
- Subjects
- *
VISIBLE spectra , *THIOPHOSPHATES , *PHOSPHITES , *OXIDIZING agents - Abstract
We hereby disclose, a visible light mediated addition of sulfenyl radicals to trialkyl phosphites to access functionalized phosphorothioates. The use of cheap and readily available Eosin Y as a photocatalyst under mild energy efficient conditions bypassing the use of external oxidants forms the chief highlight of the work. The protocol is scalable and mechanistic studies indicate that the reaction proceeds through an ionic‐Arbuzov like pathway from phosphoranyl radicals. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
48. Direct Synthesis of Dialkylphosphites from White Phosphorus.
- Author
-
Cai, Ziman, Zeng, Xiangzhe, Zhang, Yumeng, Liu, Yan, Tang, Guo, and Zhao, Yufen
- Subjects
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NONFERROUS metals , *PHOSPHORUS , *SILICA gel , *PEROXYMONOSULFATE , *PHOSPHITES , *POTASSIUM bromide - Abstract
Dialkyl phosphites (DAPIs), traditionally prepared from hazardous and corrosive PCl3, are the fundamental reactive starting materials used in organophosphorus chemistry. Here, a KBr‐mediated synthesis of DAPIs involving P4, alcohols and water is presented. With the use of silica gel as the catalyst, oxone as the safe oxidant, industrially important (EtO)2P(O)H, (i‐PrO)2P(O)H and (MeO)2P(O)H are prepared in 70–90% yields. Furthermore, rare metal extractant bis(2‐ethylhexyl) phosphate (D2EHPA) is obtained in 73% yield. The reaction is characterized by a complete conversion of white phosphorus. Moreover, this method can be easily adapted to large‐scale preparation. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
49. Findings in the Area of Chemicals and Chemistry Reported from Council of Scientific and Industrial Research (CSIR) National Chemical Laboratory (Phosphite Mediated Molecular Editing via Switch To meta-c-h Alkylation of...).
- Subjects
PHOSPHOROUS acid ,ORGANIC chemistry ,ALKYL group ,REPORTERS & reporting ,PHOSPHORIC acid - Abstract
Research conducted at the Council of Scientific and Industrial Research (CSIR) National Chemical Laboratory in Pune, India, focused on the isoquinoline core found in bioactive natural products. The study developed a new approach for phosphite-mediated alkyl migration, resulting in ortho-C-H alkylation via N-alkylation of isoquinoline. This research has implications for the development of isoquinoline-based drugs and molecules currently under clinical trials. The findings highlight the potential for diverse multi-C-H bond functionalization and regiodivergent ortho, meta-dialkylations of isoquinolines. [Extracted from the article]
- Published
- 2025
50. Metagenomics-guided analysis of microbial chemolithoautotrophic phosphite oxidation yields evidence of a seventh natural CO2 fixation pathway
- Author
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Figueroa, Israel A, Barnum, Tyler P, Somasekhar, Pranav Y, Carlström, Charlotte I, Engelbrektson, Anna L, and Coates, John D
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Genetics ,Carbon Dioxide ,Chemoautotrophic Growth ,Deltaproteobacteria ,Metagenomics ,Oxidation-Reduction ,Phosphites ,Sewage ,Wastewater ,Water Microbiology ,Water Purification ,phosphite oxidation ,carbon fixation ,metagenomics ,formatotrophic ,reductive glycine pathway - Abstract
Dissimilatory phosphite oxidation (DPO), a microbial metabolism by which phosphite (HPO32-) is oxidized to phosphate (PO43-), is the most energetically favorable chemotrophic electron-donating process known. Only one DPO organism has been described to date, and little is known about the environmental relevance of this metabolism. In this study, we used 16S rRNA gene community analysis and genome-resolved metagenomics to characterize anaerobic wastewater treatment sludge enrichments performing DPO coupled to CO2 reduction. We identified an uncultivated DPO bacterium, Candidatus Phosphitivorax (Ca. P.) anaerolimi strain Phox-21, that belongs to candidate order GW-28 within the Deltaproteobacteria, which has no known cultured isolates. Genes for phosphite oxidation and for CO2 reduction to formate were found in the genome of Ca. P. anaerolimi, but it appears to lack any of the known natural carbon fixation pathways. These observations led us to propose a metabolic model for autotrophic growth by Ca. P. anaerolimi whereby DPO drives CO2 reduction to formate, which is then assimilated into biomass via the reductive glycine pathway.
- Published
- 2018
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