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The agricultural fumigant pesticide aluminum phosphide (AlP) is cardiotoxic. Water causes AlP to emit phosphine gas, a cardiac toxin that affects heart function and causes cardiogenic shock. AlP poisoning's high fatality rate is due to cardiotoxicity. This study examines how resveratrol reduces oxidative stress, mitochondrial activity, and apoptosis in human cardiac myocyte (HCM) cells. After determining the optimal doses of resveratrol using the MTT test, HCM cells were subjected to a 24-h treatment of resveratrol following exposure to AlP (2.36 μM). The levels of reactive oxygen species (ROS), superoxide dismutase (SOD) activity, mitochondrial swelling, mitochondrial cytochrome c release, and mitochondrial membrane potential (MMP) in HCM cells were investigated. Also, the expression of Bax and Bcl-2, caspace-3 activity, and apoptosis were assessed. The present investigation revealed that AlP substantially increased the level of ROS and decreased SOD activation, which were significantly modulated by resveratrol in a dose-dependent manner. Moreover, AlP induced an elevation of mitochondrial swelling, cytochrome c release, and MMP collapse. Co-administration of resveratrol significantly reduced above mitochondrial markers. AlP also significantly upregulated BAX and downregulated Bcl-2 expression, elevated caspace-3 activity, and apoptosis. Resveratrol co-administration was able to meaningfully modulate the mentioned parameters and finally reduce apoptosis. In conclusion, resveratrol, via its pleotropic properties, significantly demonstrated cytoprotective effects on HCM cytotoxicity induced by AlP. [ABSTRACT FROM AUTHOR]

Phosphine (PH3) is a methyl bromide alternative with the potential to control surface pests of New Zealand avocados as a pre-export disinfestation treatment. 'Hass' avocado fruit were treated with PH3 (as ECO2FUME® (2% PH3, 98% CO2 (w/w); Cytec Industries Inc.)). at 500, 750 and 1,500 ppm for 24, 48 and 72 h at 5–6 °C, along with vials containing mould mites (Tyrophagus communis) and greenhouse thrips (Heliothrips haemorrhoidalis). Fruit were then stored at 5 °C for three weeks, external quality assessed, and internal fruit quality assessed after ripening at 20 °C. PH3 treatments had no impact on external fruit quality, nor on skin colouration, and only minor increase in softening compared to control at 24 h, but not 48 or 72 h. Complete (100%) mortality was achieved for thrips at all PH3 concentrations for 48 h. However, only ∼50% mould mite mortality was achieved at the highest PH3 concentration of 1,500 ppm for 72 h; although this treatment did provide a significant reduction in rots and internal disorders. This initial study demonstrates that longer-duration treatments and higher PH3 concentrations improves fruit quality compared with controls, mainly by reducing rots. These treatments fully controlled thrips but provided only partial control of mould mites. [ABSTRACT FROM AUTHOR]

Tris(3-hydroxypropyl)phosphine (THPP) was shown to be a more powerful reductant than tris(2-carboxyethyl)phosphine (TCEP), but its oxidation kinetics and mechanisms were scarcely investigated. The reduction of single electron oxidant [IrCl6]2− by THPP was thus investigated comparatively and shown to follow overall second-order kinetics. The established logk′ versus pH profiles for THPP and TCEP were different, where k′ is the observed second-order rate constant. THPP was oxidized to (HOCH2CH2CH2)3PO, confirmed by 1H NMR spectroscopy, which is in line with the determined stoichiometry. On the other hand, the proposed reaction mechanism is similar to that suggested for the TCEP reaction. The reactivity of THPP was derived, enabling a reactivity comparison with TCEP at physiological pH. Surprisingly, the measured activation parameters for the reduction of [IrCl6]2− by P(CH2CH2CH2OH)3 and P(CH2CH2CO2−)3 were essentially identical, providing information on the transition state and on the electron transfer mode. This work also defines the pKa value of THPP under well-defined conditions (pKa = 6.97 ± 0.05 at 25.0 °C and 1.0 M ionic strength) as derived by the kinetic approach. [ABSTRACT FROM AUTHOR]

Metal phosphides are highly toxic pesticides that result in high morbidities and mortalities worldwide. This systematic review included 350 studies that fulfilled the eligibility criteria. There were significant rising trends of studies on acute aluminum phosphide (AlP) and zinc phosphide (Zn3P2) poisoning (p-values = <.001), pointing to an increased number of phosphide-intoxicated patients. Acute AlP poisoning studies represented 81%, 89.3%, and 97.7% of all descriptive, analytical, and experimental interventional studies included in this review, respectively. High AlP poisoning mortality explains great research interest in AlP poisoning. Thus, after 2016, nearly half (49.7%) of studies on acute AlP poisoning were issued. Also, 78.82% of experimental interventional studies on AlP poisoning were published after 2016. The trends of in-vitro, animal, and clinical studies on AlP poisoning significantly increased with p-values equal to.021, <.001, and <.001, respectively. Seventy-nine treatment modalities for acute AlP poisoning were pooled from 124 studies; 39 management-related case reports, 12 in-vitro studies, 39 animal studies, and 34 clinical studies. All therapeutic modalities were summarized to formulate an integrated and comprehensive overview. For clinicians, therapeutic modalities significantly decreased mortality of acute AlP poisoning in clinical trials included extracorporeal membrane oxygenation (ECMO), N-acetyl cysteine (NAC), vitamin E, glucose-insulin-potassium (GIK) infusion, fresh packed RBCs infusion, and GIT decontamination using oils. However, meta-analyses are needed to provide solid evidence regarding their efficacies. To date, there is no effective antidote nor evidence-based standardized protocol for managing acute AlP poisoning. This article outlined the potential research gaps in phosphide poisoning that might promote and direct future medical research in this context. [ABSTRACT FROM AUTHOR]

The aim is to assess the prevalence and knowledge on acute occupational exposure to phosphine in the shipping industry. We followed PRISMA guidelines for scoping review. We searched in 4 databases without language and date restrictions for scientific articles in peer-reviewed and gray literature. We found 13 peer-reviewed articles and 63 articles in gray literature. These covered 56 incidents from 1963 to 2019 for a total of 254 victims and 22 fatalities. There is an increase in the number of reported cases over the last 20 years. Neurologic and gastrointestinal symptoms are predominant, and hospitalization is needed in 80% of cases. Our review underlined the principal risk as gas exposure through leaks between holds and the ventilation system. Further studies on the knowledge and the prevention in order to improve good practices onboard, prevent the risk of fire explosion, and a global reporting system of new cases are recommended. [ABSTRACT FROM AUTHOR]

Recently, advanced ab initio computations were used to generate the three-dimensional potential energy surface (3D-PES) of the phosphine–He (PH3–He) van der Waals complex along the intermonomer coordinates. This 3D-PES describes correctly the complex features of the intermolecular interactions between PH3 and He, which are on the origin of pressure broadening phenomena. At present, we take advantage of this accurate 3D-PES to compute the phosphine line broadenings perturbed by He at room temperature. First, we adjusted this 3D-PES by a new ‘fractional’ function in order to be able to incorporated it into our collisional broadening calculation code. Then, we considered the semi-classical model of Modified Robert and Bonamy improved by so-called the notion of exact trajectory to deduce the He-broadening coefficients of phosphine lines at room temperature. Room temperature data are given in the case of different branches of the parallel, ν2, and perpendicular, ν4, PH3 vibrational bands. Our results show an improved agreement with the experimental measurements. This work should be of great help for the precise determination of PH3 abundances in planetary atmospheres spectra. [ABSTRACT FROM AUTHOR]

This study has investigated the adsorption of phosphine toxic gas molecule on monolayer graphene, bilayer graphene and twisted bilayer graphene with, and without Magnesium impurity. The results of absorption energy studies using density functional theory (DFT) showed that bilayer graphene provides better adsorption than monolayer graphene and a difference in adsorption energy will be observed for twisted bilayer graphene with a rotation angle of 21.78°. By adding Mg impurity to the configurations, the sensitivity, and working temperature of the twisted bilayer graphene with Mg impurity increase compared to twisted bilayer graphene. Also, working temperature, and value of adsorption energy were calculated for bilayer graphene with Mg impurity less than Mg-doped twisted bilayer graphene, and monolayer graphene with Mg impurity. [ABSTRACT FROM AUTHOR]

The search for life elsewhere in the universe is one of the central aims of science in the twent-first century. While most of this work is aimed at planets orbiting other stars, the search for life in our own Solar System is an important part of this endeavour. Venus is often thought to have too harsh an environment for life, but it may have been a more hospitable place in the distant past. If life evolved there in the past then the cloud decks of Venus are the only remaining niche where life as we know it might survive today. The discovery of the molecule phosphine, PH 3 , in these clouds has reinvigorated research looking into the possibility of life in the clouds. In this review we examine the background to studies of the possibility of life on Venus, discuss the discovery of phosphine, review conflicting and confirming observations and analyses, and then look forward to future observations and space missions that will hopefully provide definitive answers as to the origin of phosphine on Venus and to the question of whether life might exist there. [ABSTRACT FROM AUTHOR]

In this report, two diiron ethane-1,2-dithiolate carbonyl complexes with bridging 1,3-bis(diphenylphosphino)propane (dppp) or tris(3-fluorophenyl)phosphine have been synthesized and characterized. Treatment of complex [Fe2(CO)6(µ-SCH2CH2S)] (1) with a diphosphine ligand dppp or a monophosphine ligand tris(3-fluorophenyl)phosphine using Me3NO·2H2O as the decarbonylating reagent afforded the corresponding derivatives [{Fe2(CO)5(µ-SCH2CH2S)}2(Ph2PCH2CH2CH2PPh2)] (2) and [Fe2(CO)5(µ-SCH2CH2S){P(3-C6H4F)3}] (3) in 82% and 92% yields, respectively. Complexes 2 and 3 have been characterized by elemental analysis, IR, NMR spectroscopy, as well as confirmed by single crystal X-ray diffraction analysis. Moreover, the electrochemistry of these complexes were studied by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

Four new dinuclear iridium(I) complexes were synthesized from the di(N-heterocyclic carbene) ligand precursors 1,1′-methylene-bis(3-benzyl-imidazolium)dichloride and 1,1′-methylene-bis(3-(2,4,6-trimethylbenzyl)imidazolium)dichloride. The complexes were fully characterized by spectroscopic methods, HR-MS (ESI) spectrometry, furthermore, the structure of complexes 1 and 2 were determined by single-crystal X-ray diffraction. Complexes 3a and 3b which have sulfonated triphenylphosphine ligands, were successfully used under mild conditions as catalysts in reduction reaction of ketones via hydrogen transfer from aqueous 2-propanol, and for hydrogenation of alkynes in aqueous-organic biphasic systems. [ABSTRACT FROM AUTHOR]

The phosphorus–oxygen bond formation reactions often observed for the sterically crowded triarylphosphines and their radical cations were studied by DFT calculation. The oxidations of the trimethyl-, triphenyl-, and trimesityl-phosphines to the corresponding phosphine oxides with peroxides are shown to proceed through the SN2 like transition states and the overall influence of the steric hindrance on the activation energy is limited. The reaction of the radical cation of tris(2,4,6-triisopropylphenyl)phosphine with oxygen to give the heterocyclic phosphonium cation is modeled by employing (2,6-diisopropylphenyl)diphenylphosphine and the comparison of the intermediates suggests highly exergonic nature of the reaction. [ABSTRACT FROM AUTHOR]

The potential detection of ppb levels phosphine (PH3) in the clouds of Venus through millimeter-wavelength astronomical observations is extremely surprising as PH3 is an unexpected component of an oxidized environment of Venus. A thorough analysis of potential sources suggests that no known process in the consensus model of Venus' atmosphere or geology could produce PH3 at anywhere near the observed abundance. Therefore, if the presence of PH3 in Venus' atmosphere is confirmed, it is highly likely to be the result of a process not previously considered plausible for Venusian conditions. The source of atmospheric PH3 could be unknown geo- or photochemistry, which would imply that the consensus on Venus' chemistry is significantly incomplete. An even more extreme possibility is that strictly aerial microbial biosphere produces PH3. This paper summarizes the Venusian PH3 discovery and the scientific debate that arose since the original candidate detection one year ago. [ABSTRACT FROM AUTHOR]

The CAL-B-mediated kinetic resolution of racemic 2-hydroxymethylphenyl-(methyl)phenylphosphine and its P-BH3 analogue gave, via their enantioselective monoacetylation, the corresponding monoacetates and unreacted substrates in moderate yields and with indeterminate enantiomeric excess, depending on the solvent applied. The P-BH3 analogues were transformed into 2-aminomethyl derivatives via O-tosyl or O-mesyl intermediates, which will be checked as tridentate catalyst/ligands in asymmetric synthesis. [ABSTRACT FROM AUTHOR]

Phosphorus-based Mannich-type reactions (phospha-Mannich reactions) of primary or secondary phosphines with carbonyl compounds and amines (R2NH, RNH2, and NH3) provide a powerful synthetic tool in the worldwide search for future ligands. The variety of amines and phosphines available allows for designing and fine-tuning water-soluble, chiral, macrocyclic, pincer, tripodal, photoactive, and etc., phosphine ligands with P–C–N linkage(s) (P,N-acetals). Aminized supports and amine-terminated dendrimers can easily be phosphine-functionalized by phospha-Mannich reactions, and used in reusable heterogeneous catalysts. If CH2O is used as a C-component, its stable adducts with phosphines, that is, RP(CH2OH)2 and R2PCH2OH, are often used in syntheses of P,N-acetals as they are less toxic and non-pyrophoric analogs of the phosphines, whereas other carbonyl compounds are usually converted into imines or iminium salts. In phospha-Mannich reactions, tertiary phosphines form a P+–C–N linkage (P+,N-acetals) that can easily be broken by bases, realizing imine, or iminium cations, and are used as imine/iminium donors in organic syntheses. [ABSTRACT FROM AUTHOR]

Two diiron ethane-1,2-dithiolate complexes were prepared and structurally characterized. Reactions of the parent complex [Fe2(CO)6(μ-SCH2CH2S)] (1) with tris(4-trifluoromethylphenyl)phosphine or triethyl phosphite and Me3NO·2H2O as the oxidative reagent resulted in the formation of the phosphine-substituted analog [Fe2(CO)5{P(4-C6H4CF3)3}(μ-SCH2CH2S)] (2) and phosphite-substituted analogue [Fe2(CO)5{P(OCH2CH3)3}(μ-SCH2CH2S)] (3) in 84% and 78% yields, respectively. The new complexes 2 and 3 were characterized by elemental analysis, IR, NMR spectroscopy, and single crystal X-ray diffraction analysis. Moreover, the electrochemical properties of both complexes were studied by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

The mechanisms for water exchange on [Zn(L)H2O]2+⋅H2O (L = tren: tris(2-aminoethyl)amine, trep: tris(2-phosphinoethyl)phosphine, and tres: tris(2-arsinoethyl)arsine) were studied using density functional theory (B3LYP/6-311 + G**) and evaluated by MP2 and B3LYP(PCM) energy calculations. The activation barriers for the water exchange reaction on [Zn(L)H2O]2+⋅H2O (L = tren, trep and tres) are (B3LYP/6-311 + G**) 9.9, 10.13 and 11.23 kcal mol−1, respectively. Topological analyses of the investigated ground state complexes were performed. The energy and structural data support an associative interchange (Ia) water exchange pathway. [ABSTRACT FROM AUTHOR]

Two diiron toluene-3,4-dithiolate complexes with a phosphine ligand or a phosphite ligand were prepared and characterized. Treatment of complex [Fe2(CO)6{µ-SC6H3(CH3)S}] (1) with one equivalent of ethyldiphenylphosphine or methyldiphenylphosphinite and the decarbonylation agent Me3NO·2H2O gave analogues [Fe2(CO)5(Ph2PCH2CH3){µ-SC6H3(CH3)S}] (2) [Fe2(CO)5(Ph2POCH3){µ-SC6H3(CH3)S}] (3) and in 84% and 61% yields, respectively. Both analogues have been characterized by spectroscopy, elemental analysis, and X-ray crystallography. The electrochemical properties were probed by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

Herein reported is the facial modification of tertiary phosphine boranes R3PBH3 by selective cleaving the P-Ph bond by sodium in which the phosphide borohydride R2PNa(BH3) is quantitatively generated and could be easily quenched by electrophiles to furnish a series of new phosphine boranes in high yields. [ABSTRACT FROM AUTHOR]

In this report, we describe the preparation of two diiron butane-1,2-dithiolate pentacarbonyl complexes with tris(3-fluorophenyl)phosphine or tris(3-chlorophenyl)phosphine as mimics for the active site of [FeFe]-hydrogenases. The two complexes were synthesized by the reactions of hexacarbonyl complex [Fe2(CO)6{µ-SCH2CH(CH2CH3)S}] (1) with the corresponding tertiary phosphine ligands by using Me3NO·2H2O as the decarbonylation reagent in 70% and 66% yields, respectively. The new complexes were characterized by means of elemental analysis, spectroscopy, and X-ray crystallography. Furthermore, the electrochemistry was studied by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

In aqueous HBr solution (58% w/w), 1,3,5-triaza-7-phosphaadamantane (PTA) yielded the hitherto unknown triprotonated PTA, as single crystals. In addition, the same reaction mixture deposited crystals of [O = P(CH2NH3)3]Br3 (2), formed presumably by ring opening of [PTA-H3]Br3 (3) and oxidation of the resulting [P(CH2NH3)3]Br3 (1). The solid state structure of 2 and 3 were determined by X-ray diffraction. In water/methanol mixtures, reaction of 1 and [{(η6-C10H14)RuBr2}2] yielded the half-sandwich [(η6-C10H14)RuBr2{P(CH2NH3)3}]Br3 (4) which –in aqueous solution– spontaneously afforded the dinuclear [(η6-C10H14)RuBr2{μ4-P(CH2NH2)3}Ru(η6-C10H14)]Br2 (5). [ABSTRACT FROM AUTHOR]

This review article focuses on 1λ3-phosphaalkene compounds derived from phosphines containing at least one silicon-phosphorous bond. 1λ3-Phosphaalkene compounds are of high value as they are used to form several phosphorous compounds containing a transition metal and main group elements. In addition to the fact that different kinds of 1λ3-phosphaalkynes are prepared from 1λ3-phosphaalkenes. Both families of phosphorous compounds; 1λ3-phosphaalkenes and 1λ3-phosphaalkynes have become important to chemists, as they are used in preparing several phosphorous compounds to be used as homogeneous catalysts in chemical reactions. [ABSTRACT FROM AUTHOR]

Conjugate addition of the long chain dialkyl phosphites to electron-deficient alkenes under PBu3 catalysis afforded the corresponding phosphonates in good yields in a short reaction time. Long chain alkyl groups in the phosphites were well tolerated in this transformation. The products of this reaction are of particular interest as components of lubrication oil composition. [ABSTRACT FROM AUTHOR]

Herein, we report the preparation and characterization of two diiron carbonyl complexes with ethyldiphenylphosphine or dicyclohexylphenylphosphine. Me3NO-driven decarbonylation of complex [Fe2(CO)6(µ-SCH2CH2CH2S)] (1) with the corresponding phosphine ligands afforded the products [Fe2(CO)5(Ph2PCH2CH3)(µ-SCH2CH2CH2S)] (2) and [Fe2(CO)5PhP(C6H11)2(µ-SCH2CH2CH2S)] (3) in 91% and 84% yields, respectively. The structures of complexes 2 and 3 have been identified by spectroscopy, elemental analysis, and X-ray diffraction analysis. Moreover, the electrochemistry was investigated by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

The reaction of tris(trimethylsilyl)phosphine with dimethylaluminum chloride in 1,2-dimethoxyethane (monoglyme) displays an important role as building blocks that results in the production of novel tetramethyl phosphonium dichlorodimethylaluminate and the already known dimer compound (bis(2,2-methoxy-ethanolato-O,O′)-tetramethyl-di-aluminum). The newly formed tetramethyl phosphonium dichlorodimethylaluminate [(CH3)4P]+[(CH3)2AlCl2]− crystallizes in the monoclinic space group P21/c, having unit cell with lattice constants a = 7.522, b = 11.644, c = 14.841 Å, and β = 99.32° includes four formula units. The mean values of the bond lengths are P-C 1.787 Å, Al-Cl 2.224 Å, and Al-C 1.966 Å. Both phosphorus and aluminum are tetrahedrally surrounded in organophosphonium-based cations and organoaluminium-based anions. The geometry of the dichlorodimethylaluminate anion shows a distorted tetrahedron. [ABSTRACT FROM AUTHOR]

The reactivity of the previously reported organonickel σ-complex [NiBr(Mes)(bpy)], where Mes = 2,4,6-trimethylphenyl, bpy = 2,2′-bipyridine, toward phosphine PH3 was investigated. The reaction leads to primary mesitylphosphine MesPH2 as the main product and dimesitylphosphine Mes2PH as secondary product with the nickel complex as transmetalating agent. The formed MesPH2 reacts with an excess of the complex giving Mes2PH as the major product. [ABSTRACT FROM AUTHOR]

The reactivity of the previously reported organonickel σ-complex [NiBr(Mes)(bpy)], where Mes = 2,4,6-trimethylphenyl, bpy = 2,2′-bipyridine, toward phosphine PH3 was investigated. The reaction leads to primary mesitylphosphine MesPH2 as the main product and dimesitylphosphine Mes2PH as secondary product with the nickel complex as transmetalating agent. The formed MesPH2 reacts with an excess of the complex giving Mes2PH as the major product. [ABSTRACT FROM AUTHOR]

A three-component reaction between barbituric/thiobarbituric acid, phosphines, and dialkyl acetylenedicarboxylates in dry acetonitrile led to the formation of barbiturate/thiobarbiturate-functionalized stable zwitterionic salts in a one-pot process. When trialkyl phosphites were used instead of phosphines, barbiturate/thiobarbiturate-functionalized phosphonates were obtained in good yields. [ABSTRACT FROM AUTHOR]

Tetrakis(hydroxymethyl)phosphonium chloride (THPC) and sulfate (THPS) are of importance in the textile industry as flame retardants, in the oil industry as scale-removers, as biocides for water systems, in the leather industry as tanning agents, in nanochemistry as reductants and stabilizers of nanoparticles, and as oxygen-scavengers in medical uses. In the majority of cases, THPC and THPS themselves are not chemically active and solely play a role of reservoirs for the more reactive species tris(hydroxymethyl)phosphine (THP) and/or formaldehyde. The contents of THPC/THPS solutions greatly depend on pH, which is now recognized as a key factor, for example, in metal hydrosol preparations, biocidal activity, and ecotoxicity. This review is intended to reveal and explain the complex behavior of THP and (HOCH2)4P+ salts in aqueous solutions, conditions that might lead to potential hazardous compounds such as formaldehyde, hydrogen gas, phosphine PH3, and bis(chloromethyl)ether. Literature data on their toxicities are reviewed. [ABSTRACT FROM AUTHOR]

B−H⋯π interaction has attracted increasing attention after its experimental and theoretical verifications in [ Ir(PR3)(S2C2B10H10)] (R = C6H4X, X = H, F, OMe) complexes. In such a template, the entropic factors are excluded by using triphenylphosphines as sterically crowding ligands, which leads to the direct observation of B−H⋯π hydrogen bonds at room temperature in both solution and solid state. In this work, new Ir − dithiolene-o-carborane templates with sterically less crowding mono/diphenylphosphine ligands were designed and experimentally synthesised. As a result, non-covalent B−H⋯π hydrogen bonds were detected at low temperatures (down to −80°C) in C1 by using low temperature NMR techniques. Furthermore, variable temperature NMR measurement of C0 with triphenylphosphine ligation was also performed which indicates the slow rotation of Ir−P bond and the reinforced B−H⋯π interaction at low temperature. These experimental results are consistent with the previous theoretical prediction of the B−H⋯π interaction at low temperature in the B2H6⋯benzene model. Additionally, if monophosphine ligand is replaced by diphosphine, a new type of intermolecular B−H⋯π interaction has been crystallographically observed in solid state. [ABSTRACT FROM AUTHOR]

The sterically crowded triarylphosphine bearing two phenothiazine moieties as redox sites was synthesized. The cyclic voltammogram of the phosphine exhibits three-step reversible oxidation, and the comparison with that of the triarylphosphine bearing one phenothiazine moiety suggests delocalization of positive charges during redox process. [ABSTRACT FROM AUTHOR]

Five new silver(I) complexes were synthesized with mixed ligands of thiosemicarbazone derivatives and diphenyl(p-tolyl)phosphine in search of new biologically active compounds. A CHN elemental analysis, powder X-ray diffraction (PXRD) data and several spectroscopic techniques such as Fourier-transform infrared spectroscopy, energy-dispersive X-ray, 1H, 13C, and 31P{1H} NMR were performed to elucidate the structure of these complexes. Elemental analysis suggested that the stoichiometry of the complexes formed by the reaction of silver nitrate with thiosemicarbazone in the presence of (p-tolyl)PPh2 was indeed 1:2:1 molar ratio. The silver ions were discovered to be coordinated to the sulfur of thiosemicarbazone and phosphorus of (p-tolyl)PPh2, having a tetrahedral geometry based on the spectroscopic data obtained. The PXRD patterns were studied to see the degree of crystallinity of the complexes. The in vitro antiproliferative activity of these complexes was investigated toward the MDA-MB-231 and MCF-7 breast cancer cell lines, as well as the HT-29 colon cancer cell line, which yielded IC50 values in low micromolar range. The antiplasmodial activity of these complexes was also examined against chloroquine-resistant Plasmodium falciparum parasite which demonstrated good activity and further tested for their selectivity index. [ABSTRACT FROM AUTHOR]

This review provides an overview of recent developments in the area of aqueous biphasic hydroformylation of higher olefins using metal catalysts and surfactants, cosolvents, thermoregulated ligands, cyclodextrins, and most importantly emerging water-soluble nonphosphine ligands. Water-soluble phosphine ligands have been widely explored for aqueous biphasic hydroformylation; however, phosphines are generally expensive and are prone to oxidation hence the recent interest in exploring other ligands. Various approaches have been used to introduce hydrophilicity to the ligands. The catalytic activity of monometallic and heterobimetallic systems containing nonphosphine ligands in aqueous biphasic media is emphasized in this review. [ABSTRACT FROM AUTHOR]

Phosphorous and sulfur co-doped carbon nanotubes (PSCNTs) has prepared from the catalytic chemical vapor deposition (CVD) method, starting from available materials and cheap catalyst. Triphenyl phosphine and sulfur were applied in first zone and the catalyst applied in second zone to prepare the product from acetylene gas at 720 °C. The structure of product was confirmed using field emission scanning electron microscopy (FESEM) and the presence of phosphorous and sulfur atoms was defined using energy-dispersive X-ray spectroscopy (EDS) method. Thermal behavior of the prepared PSCNT was analyzed from thermogravimetric analysis (TGA) and differential thermal analysis (DTA) in 25-890 °C, showing total 25% weight loss. Moreover, XRD patterns and Raman spectrum were obtained to define more properties of the product. Finally, the electrocatalytic ability of the prepared PSCNT in oxygen reduction reaction (ORR) was analyzed using cyclic voltammetry (CV) and linear sweep voltammetry (LSV) diagrams. The obtained diagrams showed appropriate catalytic activity in the ORR region. [ABSTRACT FROM AUTHOR]

Phosphine-borane complexes are recently developed redox-active drugs that are neuroprotective in models of optic nerve injury and radioprotective in endothelial cells. However, a single dose of these compounds is short-lived, necessitating the development of sustained-release formulations of these novel molecules. We screened a library of biodegradable co- and non-block polyester polymer systems for release of incorporated phosphine-borane complexes to evaluate them as drug delivery systems for use in chronic disease. Bis(3-propionic acid methyl ester)phenylphosphine borane complex (PB1) was combined with biodegradable polymers based on poly(D,L-lactide) (PDLLA), poly(L-lactide) (PLLA), poly(caprolactone) (PCL), poly(lactide-co-glycide) (PLGA), or poly(dioxanone-co-caprolactone) (PDOCL) to make polymer microdiscs, and release over time quantified. Of 22 polymer-PB1 formulations tested, 17 formed rigid polymers. Rates of release differed significantly based on the chemical structure of the polymer. PB1 released from PLGA microdiscs released most slowly, with the most linear release in polymers of 60:40 LA:GA, acid endcap, Mn 15 000-25 000 and 75:25 LA:GA, acid endcap, Mn 45 000-55 000. Biodegradable polymer systems can, therefore, be used to produce sustained-release formulations for redox-active phosphine-borane complexes, with PLGA-based systems most suitable for very slow release. The sustained release could enable translation to a clinical neuroprotective strategy for chronic diseases such as glaucoma. [ABSTRACT FROM AUTHOR]

The present paper discusses the electrophilic cyclization and addition reactions of 3-(α- or β-hydroxyalkyl)-allenylphosphonates and phosphine oxides. Treatment of 3-(α- or β-hydroxy-alkyl)-allenylphosphonates with electrophiles takes place with 5-endo-trig cyclization and gives 2-methoxy-2,5-dihydro-1,2-oxaphosphole 2-oxides as a result of the neighboring phosphonate group participation in the electrophilic cyclization. On the other hand, 3-(α- or β-hydroxyalkyl)-alk-(1E)-en-1-yl phosphine oxides were prepared by chemo-, regio-, and stereoselective electrophilic addition to the C2-C3-double bond in the 3-(α- or β-hydroxyalkyl)-alka-1,2-dienyl phosphine oxides and subsequent attack of the external nucleophile (halide anion). The paper proposes a possible mechanism that involves electrophilic cyclization and addition reactions of the phosphorylated (α- or β-hydroxyalkyl)allenes. [ABSTRACT FROM AUTHOR]

A less expensive and more environmentally friendly Zn(OTf)2-catalyzed dehydrative coupling reaction of propargyl alcohols with diarylphosphine oxides is reported. The reaction takes place under mild and solvent free conditions, and features a high regioselectivity to provide an effective method for the synthesis of some diarylphosphinyl allenes in moderate to high yields. [ABSTRACT FROM AUTHOR]

The broadening, shifting and mixing coefficients of the doublet spectral lines in the ν2 and ν4 bands of PH3 perturbed by H2 have been determined at room temperature. Indeed, the collisional spectroscopic parameters: intensities, line widths, line shifts and line mixing parameters, are all grouped together in the collisional relaxation matrix. To analyse the collisional process and physical effects on spectra of phosphine (PH3), we have used the measurements carried out using a tunable diode-laser spectrometer in the ν2 and ν4 bands of PH3 perturbed by hydrogen (H2) at room temperature. The recorded spectra are fitted by the Voigt profile and the speed-dependent uncorrelated hard collision model of Rautian and Sobelman. These profiles are developed in the studies of isolated lines and are modified to account for the line mixing effects in the overlapping lines. The line widths, line shifts and line mixing parameters are given for six A1 and A2 doublet lines with quantum numbers K = 3n, (n = 1, 2, …) and overlapped by collisional broadening at pressures of less than 50 mbar. [ABSTRACT FROM AUTHOR]

We reported the synthesis of tris(pyridyl)phosphine selenide (TppSe) and tris(4-methylpyridin-2-yl)phosphine selenide (MeTppSe), which were prepared by a simple and straightforward one-pot method with red phosphorus in a KOH/DMSO suspension, and treatment of resulted phosphines with selenium in hot toluene. These compounds were characterized by mass spectroscopy, 1H, 13C and 31P NMR spectroscopies and the structure of MeTppSe was characterised by a single-crystal X-ray diffraction. Furthermore, The reactions of selenides with Fe(ClO4)2·6H2O afforded two new iron(II) mononuclear metal complexes [Fe(TppSe)2][ClO4]2·3DMF (1) and [Fe(MeTppSe)2][ClO4]2·2DMF (2). Detailed structural analyses and magnetic susceptibility measurements confirm no spin transition from low-spin to the high-spin state between 2 and 300 K in two iron(II) complexes. [ABSTRACT FROM AUTHOR]

Efficient Mizoroki-Heck couplings were obtained using a very easily synthesizable palladium(II) complex of hemilabile N-O ligand (picolinate), with high turnover frequencies up to >10,000 h−1, in just 15 min, with high selectivity of >99% to the desired products. Wide applicability of the simple-looking palladium complex catalyst was established with differently functionalized substrates. Catalyst screening studies revealed intricate details of dependence of catalyst performance on different reaction parameters and conditions and arriving at the optimized facile methodology. [ABSTRACT FROM AUTHOR]

The polymeric precursor [RuCl2(CO)2]n reacts with the ligands, P∩P (a, b) and P∩O (c, d), in 1:1 M ratio to generate six-coordinate complexes [RuCl2(CO)2(ƞ2-P∩P)] (1a, 1b) and [RuCl2(CO)2(ƞ2-P∩O)] (1c, 1d), where P∩P: Ph2P(CH2)nPPh2, n = 2(a), 3(b); P∩O: Ph2P(CH2)nP(O)Ph2, n = 2(c), 3(d). The complexes are characterized by elemental analyses, mass spectrometry, thermal studies, IR, and NMR spectroscopy. 1a-1d are active in catalyzed transfer hydrogenation of acetophenone and its derivatives to corresponding alcohols with turnover frequency (TOF) of 75-290 h−1. The complexes exhibit higher yield of hydrogenation products than catalyzed by RuCl3 itself. Among 1a-1d, the Ru(II) complexes of bidentate phosphine (1a, 1b) show higher efficiency than their monoxide analogs (1c, 1d). However, the recycling experiments with the catalysts for hydrogenation of 4-nitroacetophenone exhibit a different trend in which the catalytic activities of 1a, 1b, and 1d decrease considerably, while 1c shows similar activity during the second run. [ABSTRACT FROM AUTHOR]

Two monosubstituted diiron complexes, namely (µ-SCH2CH2CH2S-µ)Fe2(CO)5L (L = P(2-C4H3O)3, 2; Ph2PCH2CH2CH3, 3), have been prepared by the carbonyl substitution of the parent complex (µ-SCH2CH2CH2S-µ)Fe2(CO)6 (1) with the corresponding monophosphine ligands in the presence of Me3NO·2H2O. The new complexes were characterized by elemental analysis, spectroscopy and single crystal X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Phosphorus K-edge X-ray absorption spectroscopy (XAS) is a highly effective experimental method for investigating metal-phosphorus bonding and electronic structure. Here, we provide a comprehensive review of P K-edge XAS studies of transition metal complexes and show how they were used to investigate a wide range of chemical phenomena, including covalent metal-ligand bonding, redox non-innocence in ligands, molecular magnetism, and luminescence. Limitations of the technique are discussed along with opportunities for future work. [ABSTRACT FROM AUTHOR]

The unified reaction valley approach (URVA) combined with the local mode, ring puckering and electron density analysis is applied to elucidate the mechanistic differences of the non-catalysed and the Au[I]-N-heterocyclic carbene (NHC)-catalysed [3,3]-sigmatropic rearrangement of allyl acetate. Using a dual-level approach (DFT and DLPNO-CCSD(T)), the influence of solvation, counter-ions, bulky and electron withdrawing/donating substituents as well as the exchange of the Au[I]-NHC with a Au[I]-phosphine catalyst is investigated. The catalyst breaks up the rearrangement into two steps by switching between Au[I]–π and Au[I]–σ complexation, thus avoiding the energy-consuming CO cleavage in the first step. Based on local stretching force constantska(C=C), we derive for the first time a quantitative measure of the π-acidity of the Au[I] catalyst; in all catalysed reactions, the bond ordern(C=C) drops from 2 to 1.65. The ring puckering analysis clarifies that all reactions start and end via a six-membered ring with a boat form. All Au[I]–σ-complex intermediates show a considerable admixture of the chair form. The non-catalysed [3,3]-sigmatropic rearrangement goes through a maximum of charge separation between the allyl and acetate units at the transition state, while all catalysed reactions proceed via a minimum of charge separation reached in the region of the Au[I]–σ-complex. [ABSTRACT FROM PUBLISHER]

A novel series of N-heterocyclic carbene-phosphine palladium(II) complexes has been synthesized and fully characterized by IR, 1H NMR, 13C NMR, and 31P NMR spectroscopies, and elemental analysis. The new N-heterocyclic carbene (NHC)-phosphine palladium(II) complexes 3a-h have been easily prepared by the reaction of the corresponding PEPPSI (pyridine-enhanced precatalyst preparation stabilization and initiation) complexes 2a-h and triphenylphosphine in dichloromethane in high yields. These complexes were applied as catalyst precursors which efficiently catalyzed Sonogashira reactions between aryl bromides and phenylacetylene to afford the corresponding products in good yields. The bulky NHC-Pd-PPh3 complexes 3 were tested against Gram-positive and Gram-negative bacteria to study their biological activity. All the complexes exhibit antibacterial against these organisms. Investigation of the anti-acetylcholinesterase activity of the studied complexes showed that compounds 3a and 3b exhibited moderate activity at 100 μg mL−1 and product 3b is the most active. [ABSTRACT FROM AUTHOR]

An efficient copper (I) halotriphenylphosphine catalyzed one-pot multicomponent reaction (MCR) of 3-substituted indole derivatives has been developed using a variety of aldehydes (aromatic, aliphatic, and heteroaromatic), indole, and active methylene substrates such as malononitrile and ethyl 2-cyano acetate. This reaction proceeds smoothly and obtained good to excellent yields (68–93%) using water as green solvent under ambient conditions. The obtained products were confirmed by 1H, 13C NMR, and mass spectroscopy techniques. The one-pot MCR occurs through formation of Knoevenagel adducts then followed by Michael addition of indole. [ABSTRACT FROM AUTHOR]

The reaction of p-acetylaniline with chlorodiphenylphosphine afforded the new ligand (p-CH3CO)C6H4N(H)PPh2 (1) in good yield. Monooxidized thioxo (p-CH3CO)C6H4N(H)P(S)Ph2 (2) and selenoxo (p-CH3CO)C6H4N(H)P(Se)Ph2 (3) were synthesized by the reaction of 1 with elemental sulfur or grey selenium. Compounds 1-3 were identified and characterized by multinuclear NMR spectroscopy (¹H, 13C, 31P, 77Se NMR) and elemental analysis. Compounds 2 and 3 were structurally characterized by single crystal X-ray diffraction which showed that the p-acetyl substituent on the aniline aromatic ring has a profound influence on the elongation of the P-N bond distance compared to several structurally characterized analogues found in literature. As such, subsequent reactions involving the P-N bond (i.e. insertion reactions) may be influenced in a favorable manner and proceed with ease. [ABSTRACT FROM AUTHOR]

Phosphine (PH3) is a toxidrome-spanning chemical that is widely used as an insecticide and rodenticide. Exposure to PH3causes a host of target organ and systemic effects, including oxidative stress, cardiopulmonary toxicity, seizure-like activity and overall metabolic disturbance. A custom dynamic inhalation gas exposure system was designed for the whole-body exposure of conscious male Sprague-Dawley rats (250–350 g) to PH3. An integrated plethysmography system was used to collect respiratory parameters in real-time before, during and after PH3exposure. At several time points post-exposure, rats were euthanized, and various organs were removed and analyzed to assess organ and systemic effects. The 24 h post-exposure LCt50, determined by probit analysis, was 23,270 ppm × min (32,345 mg × min/m3). PH3exposure affects both pulmonary and cardiac function. Unlike typical pulmonary toxicants, PH3induced net increases in respiration during exposure. Gross observations of the heart and lungs of exposed rats suggested pulmonary and cardiac tissue damage, but histopathological examination showed little to no observable pathologic changes in those organs. Gene expression studies indicated alterations in inflammatory processes, metabolic function and cell signaling, with particular focus in cardiac tissue. Transmission electron microscopy examination of cardiac tissue revealed ultrastructural damage to both tissue and mitochondria. Altogether, these data reveal that in untreated, un-anesthetized rats, PH3inhalation induces acute cardiorespiratory toxicity and injury, leading to death and that it is characterized by a steep dose-response curve. Continued use of our interdisciplinary approach will permit more effective identification of therapeutic windows and development of rational medical countermeasures and countermeasure strategies. [ABSTRACT FROM AUTHOR]

Extraction behaviour of trivalent americium and europium was investigated with 1-phenyl-3-methyl-4-acetyl-5-pyrazolone (HPMAP) and tri-n-octylphosphine oxide (TOPO) in a room-temperature ionic liquid, 1-methyl-3-octyl-imidazolium bis(trifluoromethylsulphonyl) imide (C8mim·Tf2N). In select cases, comparison was made using xylene, a molecular diluent. For binary extraction studies involving only PMAP, Eu3+was marginally better extracted than Am3+and the species extracted into C8mim·Tf2N conformed to species of the type M(PMAP)3(where M = Am or Eu). On the other hand, cationic species were extracted for the ternary extraction systems involving HPMAP and TOPO. Luminescence spectroscopic studies suggested no inner-sphere water molecules in the extracted species. The luminescence decay lifetime showed mono-exponentials, suggesting the extraction of single species. [ABSTRACT FROM PUBLISHER]

Three-coordinate copper halide complexes with a bidentate phosphine ligand have received much attention. Here, a series of three-coordinate dinuclear copper halide complexes containing a diphenylamino monodentate phosphine ligand, [CuX(dpnp)]2 (dpnp = N-[2-(diphenylphosphino)-4,5-dimethylphenyl]-N-phenylaniline, X = I (1), Br (2) and Cl (3)), were synthesized, and their molecular structures and photophysical properties were investigated. The structural analysis reveals that two copper(I) centers are bridged by two halogen ligands to form a dinuclear structure with a four-membered Cu2X2 ring. Crystal structures of 1–3 contain 1-D supramolecular arrays constructed by intermolecular C–H⋯π interactions. These complexes exhibit blue emission in the solid state at room temperature and have peak emission wavelengths at 483–487 nm with microsecond lifetimes (τ = 13.9–38.1 μs) and low emission quantum yields (<0.01%). The emission of complex 1 mainly originates from intraligand (IL) transition, whereas the emissions of complexes 2 and 3 are from a combination of MLCT, XLCT and IL transitions. The three complexes displayed good thermal stability. [ABSTRACT FROM AUTHOR]

Dialkyl[1,1-bis(alkylchloroalanyl)organylmethyl]phosphine•dialkylchloroalane(1/1) complexes (1a–1d) were synthesized and fully characterized. In 1a–1d, dative bonding between phosphorus or chlorine as a donor atom and aluminum as an acceptor atom results in a bicyclic system. The 31P{1H} NMR spectra of all compounds dissolved in d6-benzene indicate the presence of several isomers in solution. The 27Al{1H} NMR spectra of 1a–1d dissolved in d6-benzene as well show very broad singlets between 177 and 140 ppm. For all compounds, crystal structures consist of two fused four- and five-membered rings. The 1λ3-phosphaalkyne reacts at the Al–C bond of the starting material, whereas the Al–Cl moiety remains intact. The heterocycle isolated is a molecular complex of the underlying insertion compound and a third equivalent of dialkylaluminum chloride. The four- and five-membered rings both contain two chlorine-bridged aluminum atoms, Al3 and Al1, slightly more symmetrical than that between Al1 and Al6. In the four-membered ring the two aluminum atoms Al1 and Al6 approach each other at an average distance of 289.1 pm which tallies with the element–element distance (286.3 pm) in aluminum metal. [ABSTRACT FROM AUTHOR]