PCl3 Research Articles

CATALYSIS BY PHOSPHORUS AND SILICON COMPOUNDS IN THE SYNTHESIS OF OXYNAPHTOIC ACID ANILIDES

Catalysis of the acylation of aniline with 3-­hydroxy-2-naphthoic, 1-hydroxy-2-naphthoic, 2-hydroxy-1-naphthoic and 1-hydroxy-4-naphthoic acids by phosphorus P(III) and silicon Si(IV) compounds leads to the formation anilides of the corresponding hydroxy­naphthoic acids under mild conditions (ortho-xylene, 146.5–147 °C) in almost quantitative yield.
 Among P(III) phosphorus trichloride and tribromide; phosphorous, 1-hydroxyethyli­de­ne-di­phos­phonic, pyrophosphorous and me­ta­phos­phorous acids; trimethyl-, dimethyl- and diethylphosphites; phosph(III)azan proved to be active catalysts; among Si(IV) – tri­chloro-(methyl)silane, dichloro(ethyl)silane, dichloro­(dimethyl)silane, tetrachlorosilane and tet­ra­ethoxysilane are active.
 The catalysts were used in an amount of only 2% mole. from hydroxynaphthoic acid, which is 15–35 times less than the conventional use of the same compounds as condensing agents in the synthesis of carboxylic acid arylamides. P(V) compounds, thionyl chloride, and sulfuryl chloride practically do not exhibit catalytic activity. The presence of catalytic activity only in P(III) compounds, capable of forming phosphorous acid in the reaction mass, does not contradict to the previously proposed mechanism of P = O-nucleophilic catalysis for the reaction of substituted benzoic acids with aniline catalyzed by PCl3.
 In general, the use of P(III) and Si(IV) compounds as catalysts in the preparation of hydroxybenzoic and hydroxynaphthoic acid anilides successfully complements the range of catalysts, based on Ti(IV) compounds, previously used in the formation of substituted benzoic and naphthoic acid anilides (containing no aromatically bonded hydroxy group), allowing to create a universal method for their synthesis.

Nickel-Catalyzed Sodium Hypophosphite-Participated Direct Hydrophosphonylation of Alkyne toward H-Phosphinates.

The traditional methods for the synthesis of phosphinate esters use phosphorus trichloride (PCl3) as the phosphorous source, resulting in procedures that are often highly polluting and energy intensive. The search for an alternative approach that is both mild and environmentally friendly is a challenging, yet highly rewarding task in modern chemistry. Herein, we use an inorganic phosphorous-containing species, NaH2PO2, to serve as the source of phosphorous that participates directly in the nickel-catalyzed selective alkyne hydrophosphonylation reaction. The transformation was achieved in a multicomponent fashion and at room temperature, and most importantly, the H-phosphinate product generated is an advanced intermediate which can be readily converted into diverse phosphinate derivatives, including those bearing new P-C, P-S, P-N, P-Se, and P-O bonds, thus providing a complimentary method to classic phosphinate ester synthesis techniques.

Comparative Life Cycle Assessment of Catalytic Intermediate Pyrolysis of Rapeseed Meal

Biowaste valorization is a means for tackling resource depletion and climate change, which gives rise to environmental benefits and economic growth. One of the most known technological routes to convert biowaste into bioproducts is pyrolysis, which may conduct with and without catalyst application. The purpose of this study was to investigate an early-stage life-cycle assessment (LCA) for catalytic intermediate pyrolysis to valorize rapeseed meal, split over the scenarios using ZSM-5 and zeolite Y catalysts. Four selected environmental impact categories were assessed by IMPACT 2002+ methodology. The results revealed that the ZSM-5 catalytic pyrolysis led to bigger environmental impacts than the pyrolysis utilizing zeolite Y in all compared impact categories except global warming. The scenario that involved zeolite Y had around 20% GHG intensity greater than ZSM-5 pyrolysis. The bulk of GHG emissions mostly involved CO2 and methane generated from electricity consumption, which was provided by fossil resources. Applying ZSM-5 in the pyrolysis increased environmental burdens in non-renewable energy, respiratory inorganics, and terrestrial ecotoxicity by 140.88 MJ primary, 8.83 × 10−3 kg PM2.5 eq. and 125.63 kg TEG soil, respectively. The major driving factor of high value in mentioned categories was the manufacturing process of the ZSM-5 catalyst by utilizing natural gas and chemicals, such as phosphorus trichloride, sodium hydroxide and sodium silicate. Given that catalysts can play a substantial role in the emissions resulting from bio-based products, hence LCAs of pyrolysis should consider the potential influence of catalysts in the valorization processes. This study can predict environmental hotspots in the early stages of bio-waste valorization and show the potential defects of implanted biorefinery at pilot/industrial scales.

Fabrication of High-Quality CsPbI3 Perovskite Films with Phosphorus Pentachloride Additive for Highly Stable Solar Cells.

Fully inorganic perovskite cesium lead triiodide (CsPbI3 ) has garnered much attention from researcher for photovoltaic application because of its excellent thermal stability compared with the inorganic-organic hybrid counterparts, along with the potential to serve as the top cell in tandem devices with silicon solar cell. However, the active α-phase cubic CsPbI3 spontaneously tends to transform into the non-perovskite δ-CsPbI3 when subjected to ambient condition. This work proposes an effective method to fabricate high-quality and stable α-phase cubic CsPbI3 films by introducing phosphorus pentachloride (PCl5 ) as an additive. PCl5 acts as colloidal binder for modulating crystallization dynamics of perovskites, resulting in high-quality film and a significantly suppressed phase transition. Finally, highly stable CsPbI3 perovskite solar cells can be achieved with a power conversion efficiency up to 17.85 %, and a long-term stability in N2 filled glove box.

Design, Structural Characteristic and Antibacterial Performance of Silver-Containing Cotton Fiber Nanocomposite.

In the present study, cotton fiber was treated with phosphorus trichloride in the presence of oxygen. As a result of the subsequent hydrolysis of modified cotton fibers, phosphorus-containing fragments with acidic groups and chlorine atoms were introduced onto their surface. Afterward, silver-containing composites based on raw and modified cotton fibers were prepared using the chemical reduction method. The obtained samples were characterized in detail by Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, X-ray powder diffraction, as well as by thermogravimetric analysis, scanning electron microscopy, and energy-dispersive X-ray analysis. A comparative bioassay experiment of four samples for gram-negative (Escherichia coli) bacteria, gram-positive (Staphylococcus aureus) bacteria, and the fungus Candida albicans was carried out. These results showed the predominant antibacterial activity of the phosphorylated sample and the composite based on it. Thus, the development of these antibacterial cotton fibers using readily available reagents under relatively mild conditions could be used as potential industrial applications for the production of everyday medical textiles.

СATALYTIC METHOD FOR THE SYNTHESIS OF 3-HYDROXY-2-NAPHTOIC ACID ANILIDE

Arylamides of 3-hydroxy-2-naphthoic acid are widely used in the production of organic azo pigments, as medicines and pesticides.
 Titanium tetrachloride, tetrabutoxytitanium and polybutoxytitanates, previously used for the synthesis of the most important of them., 3-hydroxy-2-naphthoic acid anilide by boiling of the latter in aniline (184 °C), proved to be ineffective as catalysts in carrying out this reaction in ortho-xylene.
 The study of the reasons for this inhibition of catalysis showed that it can be associated with the interaction of Ti(4+) with the hydroxy group of 3-hydroxy-2-naphthoic acid, its oxidation, accompanied by a decrease in the effective charge of titanium.
 Taking into account this inhibition, in the search for new catalysts for the synthesis of 3-hydroxy-2-naphthoic acid anilide, the known literature data on the oxidizing ability (according to the values of the reaction rate constant k) with respect to phenoxyl radicals of a number of Lewis acids, including titanium tetrachloride, were used:
 SbCl5>TiCl4 >SnCl4>PCl5>AlCl3
 k, l·mol-1·sec-1 105 157 156 42 18.
 This made it possible to choose phosphorus trichloride as an effective catalyst. It is shown that this compound, in an amount of only 2% mole. from 3-hydroxy-2-naphthoic acid, allows in boiling ortho-xylene (145 °C), under relatively mild conditions, compared to boiling aniline (184 °С), to obtain anilide 3-hydroxy-2-naphthoic acid (by reaction of the latter with aniline) of good quality with a practically quantitative yield.
 Antimony trifluoride also has similar pro­perties as a catalyst, at the level of efficiency of phosphorus trichloride.
 The ability of catalysts to act as an oxidizing agent should, apparently, always be taken into account during the catalytic amidation of aromatic oxycarboxylic acids at elevated temperatures.

Synthesis of new photo-cured phosphorus-containing oligoestermethacrylates with a spacer in the structure

Objectives. To synthesize phosphorus-containing oligoestermethacrylates spatially separated by spacers of aliphatic or aromatic structure and evaluate their effect on photocuring kinetics.Methods. For determining the qualitative and quantitative composition of the synthesized compounds, the following methods were used: thin layer chromatography; chromatographic and mass spectrometry; infrared spectroscopy; 1H, 13C, 31P nuclear magnetic resonance spectroscopy; differential scanning calorimetry. The dielectric loss tangent was determined on a specially designed optical cell with an ultraviolet (UV) light source to an immittance meter. Elemental analysis was performed on an energy dispersive X-ray fluorescence spectrometer.Results. Spatially separated oligoestermethacrylates based on phosphorus trichloride containing aliphatic or aromatic spacers in the structure were synthesized. During the interaction of glycidyl methacrylate with phosphorus trichloride in the mass of the latter, reaction products were shown to be formed both according to the Krasusky rule from the side of the α-carbon atom, as well as against this rule with the formation of isomeric products. Obtaining these compounds in bulk is possible only in the presence of a homopolymerization inhibitor. The influence of the spacer structure on the curing rate of oligoestermethacrylates under the action of UV radiation has been established. It has been shown that the introduction of a spacer into the oligomer structure is accompanied by an increase in the induction period by a factor of 39 compared to a sample without a spacer.Conclusions. The results obtained indicate the possibility of obtaining new oligoestermethacrylates with aliphatic and aromatic spacers in the structure. The influence of the structure of the spacer on the kinetics of photocuring is determined.

Reaction of 1-(2-hydroxyphenyl)-3-phenylpropane-1,3-dione with some phosphorus halides: A simple synthesis of novel 1,2-benzoxaphosphinines

A simple method for design of some novel 1,2-benzoxaphosphinines 2–9, was achieved. The methodology depended on cyclization of 1-(2-hydroxy-phenyl)-3-phenylpropane-1,3-dione (1) as starting material with some phosphorus halides in dry solvent in the presence of a base. Reaction of the substrate 1 with some phosphorus halides, such as P,P-dichlorophenylphosphine, phenyl phosphonic dichloride, phenyl phosphorodichloridate, and phosphorus oxychloride in dry toluene containing triethylamine led to a predominant formation of 3-benzoyl-4-hydroxy-2H-1,2-benzoxaphosphinines 2–5, respectively. Under the same reaction conditions, the molecular structures of type 3-benzoyl-4H-1,2-benzoxaphosphinin-4-ones 6 and 7 were isolated by treatment of the substrate 1 with phosphorus pentachloride and phosphorus tribromide, respectively. In addition, the interesting 4-(1-phenyl-ethanoyl)-1,2,λ5-benzoxaphosphinines 8 and 9 were obtained by treatment of compound 1 with acetonyl and benzyl triphenylphosphonium chlorides, respectively, in dry dioxane and sodium hydride. The chemical structures of the title compounds were established by elemental analysis and spectral tools.

SYNTHESIS METHOD OF OPTICALLY PURE ENANTIOMERS OF 5-ARYL SUBSTITUTED3-METHYL‑7- NITRO‑1,2-DIHYDRO‑3H‑1,4-BENZODIAZEPIN‑2-ONES

The aim of this work is to develop a simple, fast and efficient method for the synthesis of optically pure enantiomers of some 5-aryl-substituted 3-methyl‑7-nitro‑1,2-dihydro‑3H‑1,4-benzodiazepin‑2-ones using simple reagents. In the course of the study, we found that the interaction of 2-amino‑5-nitrobenzophenone or 2-amino‑2’-chloro‑5-nitrobenzophenone with optically active L- or D‑α-alanine N‑carboxyanhydrides in the presence of two equivalents of trifluoroacetic acid does not leads to the formation of the corresponding reaction intermediates (2-amino-N-(2-benzoylphenyl)propanamide), even when refluxed for 24 hours in xylene. Acylation of 5-nitro‑2-aminobenzophenones with hydrochlorides of L- or D‑α-alanine acid chlorides, followed by cyclization under mild conditions, leads to target 3-methyl‑7-nitro‑1,2-dihydro‑3H‑1,4-benzodiazepin‑2-ones characterized by high optical purity. It is noteworthy that these reactions allow the coupling of acid chlorides derived from stereospecific α-alanines with weakly reactive 5-nitro derivatives of 2-aminobenzophenone without racemization. It is important to note that the acid chloride hydrochlorides of optically active α-alanines, which are chemically unstable and extremely sensitive to moisture, are used as building blocks in the work. In this case, acid chlorides of individual antipodes of L- or D‑α-alanine were synthesized in absolute chloroform using phosphorus pentachloride and the products were isolated by simple filtration of precipitates, without applying additional purification to them. The structure of the title compound was confirmed by spectroscopy 1H and 13C NMR, and FAB mass spectrometry methods, purity was controlled by HPLC. To analyze the optical purity of the1,2-dihydro‑3H‑1,4-benzodiazepines synthesized in this work, HPLC was applied using stationary chiral phase CiraDex®. This simple preparation method is of potential practical importance for the design and synthesis of optically pure enantiomers of various 3-alkyl derivatives of 1,2-dihydro‑3H‑1,4-benzodiazepin‑2-ones with a wide spectrum of biological activity.

Demand for quality pesticides to drive phosphorus trichloride market growth

Demand for quality pesticides to drive phosphorus trichloride market growth

CATALYSIS OF TRIVALENT PHOSPHORUS COMPOUNDS OF THE REACTIONS OF SUBSTITUTED BENZOIC ACIDS WITH ANILINE

The catalytic preparation of substituted benzanilides by the reaction of substituted benzoic acids with aniline is an important model process that has been intensively deve­lo­ped recently, in the field of the «green chemistry» concept, direct catalytic amidation, and its study is an urgent scientific and practical task.
 Within the framework of solving this problem, the catalysis of the acylation of aniline by substituted benzoic acids with trivalent phosphorus compounds P(III) was studied. It was established that P(III) in the amount of only 2% mol. from substituted benzoic acid effectively catalyze this reaction, which proceeds in boiling low-polar solvents with intensive water distillation in an air atmosphere, which leads to obtaining anilides of substituted benzoic acids with a yield close to quantitative. The new catalysts, phosphorus trichloride and tribromide, phosphorous acid, successfully complement the catalytic system tetrabutoxytitanate/polybutoxytitanate, previously used for these purposes, allowing to obtain anilides of amino­benzoic acids with greater selectivity, as well as anilides of oxybenzoic acids.
 The study of the kinetic regularities of the reaction catalyzed by phosphorus trichloride showed a weak effect of substituents: |ρ| ≤ 0.61. Hammett dependences are represented by curves with a maximum, straight line segments are characteristic only for certain groups of substituents, both for meta- and para-substituted and for orthosubstituted benzoic acids.
 One of the possible mechanisms of acylation is the formation in situ in the first mi­nutes of the reaction of aniline phosphite, which can act as an oxygen-nucleophilic catalyst, and, upon interaction with substituted benzoic acid, forms the corresponding benzoyl phosphite, which is then attacked by a free aniline molecule to obtain substituted benzanilide.
 The ortho effect for P(III) catalysis is absent or very weak, in the case of aminobenzoic acids. At the same time, anthranilic acid can form a phosphite with phosphorous acid, which directly participates in catalysis.

Cover Feature: Sequential Nucleophilic Substitution of Phosphorus Trichloride with Alcohols in a Continuous‐Flow Reactor and Consideration of a Mechanism for Reduced Over‐reaction through the Addition of Imidazole (Chem. Eur. J. 37/2022)

Sequential nucleophilic substitution of phosphorus trichloride with alcohols has been achieved. Over-reaction was suppressed by rapid mixing through micro-flow technology, and asymmetric phosphotriesters containing acid- and/or base-labile functional groups were synthesized in good to high yields. Moreover, a mechanistic study by using DFT calculations suggested interesting reaction pathways. More information can be found in the Research Article by S. Fuse and co-workers (DOI: 10.1002/chem.202200932).

Sequential Nucleophilic Substitution of Phosphorus Trichloride with Alcohols in a Continuous-Flow Reactor and Consideration of a Mechanism for Reduced Over-reaction through the Addition of Imidazole.

We demonstrate a sequential nucleophilic substitution of highly electrophilic and inexpensive phosphorus trichloride with three different alcohols in a continuous-flow reactor. A variety of alcohols including ones that contained acid- and/or basic-labile functionalities were rapidly reacted. A over nucleophilic substitution that occurred during reaction of the second alcohol was suppressed by the addition of imidazole. Density functional theory calculations of the sequential nucleophilic substitutions of alcohols were performed both with and without imidazole, and Berry pseudorotation was suggested as a rate-limiting step in both cases. Herein, we discuss the reasons for the decreased selectivity in the absence of imidazole as well as those for improved selectivity in the presence of imidazole during the second nucleophilic substitution.

Luigi chiozza. The chemistry of organic acids

Luigi Chiozza (1828-1889) was an Italian chemist who made a detailed study of the preparation, properties, and reactions of organic acids. While studying the reaction of ammonium sulfide with nitrocinnamic acid, he discovered the new compound, carbostyril (2-hydroxyquinoline). He also synthesized monochlorobenzoic acid ( o -chlorobenzoic acid) by treating the chlorination product of salicylic acid with phosphorus pentachloride with water. Alone, or with Gerhardt, he developed efficient processes for the preparation of simple and mixed acid anhydrides, as well as numerous new primaries, secondary, and ternary amides. His most important work was the artificial production of the essence of cinnamon (i.e., cinnamic aldehyde). @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:3 0 0 0 1 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0in; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman";}span.jlqj4b {mso-style-name:jlqj4b; mso-style-unhide:no;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;}div.WordSection1 {page:WordSection1;}

Особенности дисмутации арилдихлорфосфитов

The paper considers the spontaneous rearrangement, i.e., dismutation, of phosphorous acid dichlorides (aryl dichlorophosphites) into acid chlorides (diaryl chlorophosphites) with separation of phosphorus trichloride. The starting materials contained phenyl, 1- and 2-naphthols as aromatic radicals. The main patterns of dismutation of aryldichlorophosphites were revealed and the basic factors influencing the process time were determined. The dismutation parameters of aryldichlorophosphites were compared with the regularities revealed earlier for a similar process with the participation of diamidoesters of phosphorous acid containing phenyl and naphthyl substituents as an ether component. Calculations of thermodynamic functions of state, i.e., standard enthalpies of ΔfH0298 formation and S0298 entropies, for the dismutation participants, standard values of the Gibbs energy of ΔrG0298 reactions, were calculated. Calculations were carried out without taking into account the influence of the solvent and for the case of standard conditions, as well as for similar systems --- diamidoesters of phosphorous acid. The calculations allowed us to show the thermodynamic possibility of implementing dismutation of aryl dichlorophosphites at relatively low temperatures. The semi-empirical calculation method (RM1) made it possible to establish the lowest-energy conformations of diaryl chlorophosphites formed as a result of dismutation and show their fundamental difference

Characterization Studies of a GC based SAW Sensor System for Potential Detection and Identification of Toxic Environmental Gases/Vapors

The characterization of a custom-designed GC-based SAW e-Nose sensor system is presented here to study the sensing ability of the sensor system to detect and identify low medium and high toxic vapors. A semi-automated multi-vapor generator generates vapors of chemical compounds that are then exposed to the sensing system to examine its performance under various concentrations. Time-domain verses frequency response of GC-SAW Sensor is noted for repeated cycles against different chemical compounds like xylene, 1,2 dibromoethane, dimethyl sulfate, triethyl phosphate, nitrobenzene, phosphorous trichloride being tested. The generated data is examined using a principle component analysis (PCA) technique to detect a unique response for an individual chemical compound. Experimental results are reported.

A Mechanistic Study on the Formation of Dronic Acids.

Dronic acid derivatives, important drugs against bone diseases, may be synthesized from the corresponding substituted acetic acid either by reaction with phosphorus trichloride in methanesulfonic acid as the solvent or by using also phosphorous acid as the P-reactant if sulfolane is applied as the medium. The energetics of the two protocols were evaluated by high-level quantum chemical calculations on the formation of fenidronic acid and benzidronic acid. The second option, involving (HO)2P-O-PCl2 as the nucleophile, was found to be more favorable over the first variation, comprising Cl2P-O-SO2Me as the real reagent, especially for the case of benzidronate.

Tris(tetramethylguanidinyl)phosphine: The Simplest Non-ionic Phosphorus Superbase and Strongly Donating Phosphine Ligand.

We report the synthesis and properties of the much sought‐after tris(1,1,3,3‐tetramethylguanidinyl) phosphine P(tmg)3, a crystalline, superbasic phosphine accessible through a short and scalable procedure from the cheap and commercially available bulk chemicals 1,1,3,3‐tetramethylguanidine, tris(dimethylamino)‐phosphine and phosphorus trichloride. The new phosphine exhibits exceptional electron donor properties and readily forms transition metal complexes with gold(I), palladium(II) and rhodium(I) precursors. The formation of zwitterionic Lewis base adducts with carbon dioxide and sulfur dioxide was explored. In addition, the complete series of phosphine chalcogenides was prepared from the reaction of P(tmg)3 with N2O and the elemental chalcogens.

Phosphorylation of the cellulose surface with PCl3 and P(O)Cl3

The vapor-phase phosphorylation of cellulose by means of phosphorus trichloride (PCl3) and phosphorus oxychloride (POCl3) is presented. It was found that cellulose-O-dichlorophosphines (Cell-O6-PCl2) formed by the reaction of cellulose with PCl3 and cellulose-O-dichloro-oxyphosphines (Cell-O6-P(O)Cl2) formed by the reaction with P(O)Cl3 have been hydrolyzed to cellulose-O-hydrogenphosphates (P(III/V)) (Cell-O6-P(O)(H)-OH and (Cell-O6-P(O)(OH)2), respectively. Selected chemico-physical properties (SEM-EDS, 31P NMR, potentiometric titration) of both types of cellulose phosphates (Cell-O6-O-P(O)(H)-OH and Cell-O6-O-P(O)(OH)2) were compared.

Phosphorylation of chitosan (chitin) surface with PCl3

The synthesis and antimicrobial activity of copper chitosan phosphates complexes are presented. Chitosan (Cts) surface phosphorylations were achieved by its exposure to phosphorus trichloride (PCl3) vapors. The formed chitosan-dichlorophosphines (Cts-[Y-PCl2] z ; Y = N,O; z ≤ 3) were hydrolyzed to chitosan-hydrogenphosphates (Cts-[Y-P(O)(H)(OH)] z ), the chemo-physical and biological properties of which were analyzed. The performed antimicrobial tests of the synthesized Cts-[Y-P(O)(H)(OH)] z ×Cu2+ against representative Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus) revealed their potential applications as an antibacterial material.