Liquid-liquid extraction of mercury(II) with triphenylphosphine sulphide: Application to medicinal and environmental samples

A method is proposed for the separation and determination of mercury(II) in environmental samples after its extraction from salicylate solution using triphenylphosphine sulphide (TPPS) as an extractant. The extraction conditions are optimized and reported. The nature of the extracted species is ascertained by a plot of log of distribution ratio versus log of concentration of salicylate and TPPS. Received: 22 January 1997 / Revised: 7 May 1997 / Accepted: 10 May 1997     

Extraction and separation of scandium salicylate with triphenylphosphine oxide

Scandium can be extracted from 5.0 × 10^–2 mol/l sodium salicylate solution, adjusted to pH 4.0–5.0 with 0.5% triphenylphosphine oxide dissolved in toluene as an extractant. After stripping from the organic phase with 0.5 mol/l HCl it can be subsequently determined spectrophotometrically with Alizarin Red S. The method permits a separation of Sc(III) from Ti(IV), V(V), Cr(VI), Fe(III), Y(III), La(III), Ce(III), Nd(III) and Sm(III) in synthetic mixtures. The method is fast, simple and selective. Received: 6 May 1996 / Revised: 21 July 1996 / Accepted: 25 July 1996     

Extraction and determination of zinc in pharmaceutical samples

A systematic study of extraction of zinc salicylate is reported. Optimum conditions for the extraction and determination of zinc are evaluated from a critical study of the effect of pH, sodium salicylate concentration and triphenylphosphine oxide concentration. The effect of foreign ions on the extraction is also discussed. The probable composition of the species has been deduced from the extraction data. The method has been used to separate zinc from cadmium and mercury in binary mixtures and for the determination of zinc in various pharmaceutical products.     

Extraction studies of thorium(IV) with triphenylphosphine oxide

A simple method is described for the solvent extraction of thorium. Thorium is extracted quantitatively from 5·10^–3M sodium salicylate solution at pH 2.5–3.25 using 2.16·10^–2M triphenylphosphine oxide as an extractant dissolved in toluene. The extracted metal ion is stripped with hydrochloric acid (0.1M) and determined spectrophotometrically with Thoron-1 at 540 nm. The method permits separation of thorium from lanthanum, cerium, neodymium, samarium and uranium from binary mixtures and is applicable to the analysis of monazite sand. The method is precise, accurate and selective.     

Extraction and separation of scandium salicylate with triphenylphosphine oxide

Scandium can be extracted from 5.0 × 10⁻² mol/1 sodium salicylate solution, adjusted to pH 4.0–5.0 with 0.5% triphenylphosphine oxide dissolved in toluene as an extractant. After stripping from the organic phase with 0.5 mol/1 HCl it can be subsequently determined spectrophotometrically with Alizarin Red S. The method permits a separation of Sc(III) from Ti(IV), V(V), Cr(VI), Fe(III), Y(III), La(III), Ce(III), Nd(III) and Sm(III) in synthetic mixtures. The method is fast, simple and selective.     

Liquid-liquid extraction of mercury(II) with triphenylphosphine sulphide: Application to medicinal and environmental samples

A method is proposed for the separation and determination of mercury(II) in environmental samples after its extraction from salicylate solution using triphenylphosphine sulphide (TPPS) as an extractant. The extraction conditions are optimized and reported. The nature of the extracted species is ascertained by a plot of log of distribution ratio versus log of concentration of salicylate and TPPS.     

Efficient scavenging of Ph3P and Ph3P=O with high-loading merrifield resin

[see reaction]. A simple, highly effective method for removing triphenylphosphine and/or triphenylphosphine oxide from reaction mixtures is described. Commercially available high-loading chloromethylated polystyrene 1, modified in situ with NaI, acts as a scavenger resin. Several coupling reactions catalyzed by Pd(0) or Ni(0) which require the removal of triphenylphosphine are tested.     

Synthesis of hydroxyphosphoranes from triphenylphosphine and triphenylphosphine oxide

Novel hydroxyphosphoranes were synthesized using the oxidative method from triphenylphosphine, 1,1′-dihydroxydicyclohexyl, benzopinacol, and aminophenol in the presence oftert-butyl hydroperoxide. Hydroxyphosphoranes were also obtained from triphenylphosphine oxide, and the series of dihydric phenols and diols mentioned above. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1779–1781, October, 1993.     

Electroreduction of tetra-coordinate phosphonium derivatives; one-pot transformation of triphenylphosphine oxide into triphenylphosphine

Electroreduction of triphenylphosphine dichloride in acetonitrile was performed successfully in an undivided cell fitted with an aluminium sacrificial anode and a platinum cathode, wherein Al³⁺, which was electrogenerated at the anode would react as a Lewis acid with triphenylphosphine dichloride to afford tetra-coordinate chlorotriphenylphosphonium species and subsequent two-electron reduction at the cathode would give triphenylphosphine. One-pot transformation of triphenylphosphine oxide to triphenylphosphine was achieved successfully by the treatment of triphenylphosphine oxide with oxalyl chloride and subsequent electroreduction. In a similar manner, some tetra-coordinate triphenylphosphonium species derived from triphenylphosphine oxide were reduced electrochemically to triphenylphosphine in moderate yields.     

One-pot solid phase synthesis of (E)-nitroalkenes

An efficient one-pot protocol for the synthesis of (E)-nitroalkenes by reaction of aldehydes and nitroalkanes in the presence of polymer-bound triphenylphosphine, iodine and imidazole is described. Although the reaction works with similar efficiency with triphenylphosphine and its polymer-bound version, easy removal of the unwanted polymer-bound triphenylphosphine oxide and its recovery as triphenylphosphine provide the edge for practical application of the method.     

Adduct of Triphenylphosphine Oxide and Sulfuric Acid: Synthesis and Structure

Adduct of triphenylphosphine oxide and sulfuric acid was synthesized by reacting arenesulfonic acids with triphenylphosphine oxide (1 : 2) in the presence of the moisture of air. According to the X-ray diffraction data, the phosphorous atom has a distorted tetrahedral coordination. The sulfuric acid molecule is disordered over two sites and is linked with two triphenylphosphine oxide molecules through hydrogen bonds.     

Origin of the oxygen in the oxidation of triphenylphosphine by potassium persulfate—application of the 18O isotope effect in 31P NMR

Potassium persulfate oxidizes triphenylphosphine to triphenylphosphine oxide in 60% aqueous acetonitrile. It has been suggested that the oxygen of the product, triphenylphosphine oxide, might originate from solvent water, following nucleophilic attack on an intermediate phosphonium ion. We have investigated the origin of the oxygen in the oxidation of triphenylphosphine by potassium persulfate in 60% aqueous acetonitrile containing 20% [¹⁸O]water. The product was analyzed by using the ¹⁸O isotope effect in ³¹P NMR spectroscopy. The magnitude of the ¹⁸O isotope-induced shift was determined by synthesizing triphenylphosphine [¹⁸O]oxide and was found to be 0.038 ppm upfield. The product of the oxidation reaction in 20% [¹⁸O]water displayed no ¹⁸O isotope effect. The origin of the oxygen in the oxidation reaction is the persulfate ion, consistent with an alternative mechanism involving nucleophilic attack by water at the sulfur atom of a phosphonium peroxysulfate intermediate.     

Reaction of triphenylphosphine with poly(ethylene terephthalate) and certain model compounds at elevated temperature

Triphenylphosphine and poly(ethylene terephthalate) react at 370°C to produce ethylene, triphenylphosphine oxide, carbon dioxide, benzoic acid, and terephthalic acid. The reaction proceeds by the initial formation of a zwitterionic species which then generates a phosphonium ylid and leads to the observed products. Any flame retardant activity from the use of triphenyl-phosphine may be attributed to the formation of triphenylphosphine oxide. The co-production of ethylene renders triphenylphosphine a less effective flame retardant than triphenylphosphine oxide.     

μ‐Phthalocyaninato‐bis(triphenylphosphinoxidnatrium): Synthese und Kristallstruktur

μ‐Phthalocyaninato‐bis({triphenylphosphine oxide}sodium): Synthesis and Crystal Structure Blue μ‐phthalocyaninato‐bis({triphenylphosphine oxide}sodium) ( 1 ) is prepared by heating triphenylphosphine oxide with disodium phthalocyaninate at 160 °C. 1 is centrosymmetric (space group P1). The Na atom is located in a tetragonal pyramid co‐ordinating four isoindole N atoms at a distance varying between 2.409(2) and 2.438(2) Å, and one O atom at 2.198(2) Å. The Na–Na distance is 2.823(5) Å, and the Na–O–P angle is 145.5(1)°.     

Phosphonium salt-catalysed synthesis of nitriles from in situ activated oximes

A metal-free catalytic method for the conversion of aromatic and aliphatic aldoximes to nitriles at room temperature using oxalyl chloride (1.2 equiv) in combination with 5 mol % of triphenylphosphine oxide is reported. Of the many potential pathways leading from oxime to nitrile a manifold involving chlorophosphonium salt-catalysed decomposition of oxime chlorooxalates formed in situ is shown to be operative.     

Reaction of polyperoxides with triphenylphosphine

The triphenylphosphine deoxygenation of the polyperoxides, poly(styrene peroxide), poly(methyl methacrylate peroxide), and poly(α-methylstyrene peroxide) proceed via the phosphorane intermediates, which in the presence of moisture hydrolyze to give the respective diols. At higher temperatures and under dry conditions the phosphorane decomposes into epoxide and triphenylphosphine oxide. The reaction has been studied by ¹H-, ¹³C-, and ³¹P-NMR spectroscopy. The results obtained are consistent with a concerted insertion of the biphile, triphenylphosphine, into the peroxy bond and this reaction pathway seems to be new as far as the chemistry of polyperoxides is concerned. Though the aim of this investigation was to test the selective deoxygenation of polyperoxide by triphenylphosphine as a method of preparing polyethers, it turned out to be a fruitful method of synthesis of stereospecific diols. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1167–1172, 1997     

Convenient Synthesis of Substituted 2-Phenylbenzothiazoles Using Solid-Supported Triphenylphosphine

We report an improved procedure using solid-supported triphenylphosphine for the concise synthesis of biologically relevant 2-phenylbenzothiazoles featuring a variety of substituents on both the benzothiazole and phenyl rings. Substituted 2-phenylbenzothiazoles were synthesized by heating equimolar quantities of 2-aminothiophenol disulfides with benzaldehydes and p-toluenesulfonic acid in the presence of polymer-supported triphenylphosphine in dimethylformamide/toluene. Appealing features of this new method include simple isolation of product (removal of phosphine oxide by-product by filtration), avoidance of column chromatography, and good yields of substituted 2-phenylbenzothiazole products.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.     

Reaction of N-sulfinyltrifluoromethanesulfonamide with triphenylphosphine and triphenylphosphine oxide

The reaction of N-sulfinyltrifluoromethanesulfonamide with triphenylphosphine and triphenylphosphine oxide or of trifluoromethanesulfonamide with dichloro(triphenyl)phosphorane leads to trifluoro-N-(triphenyl-λ⁵-phosphanylidene)methanesulfonamide, which is hydrolyzed to trifluoromethanesulfonamide and triphenylphosphine oxide via the intermediate trifluoro-N-[hydroxy(triphenyl)phosphoranyl]methanesulfonamide.     

Elucidation of the Structure of Products of Triphenylphosphine Electrooxidation in the Presence of Camphene

The structure of the products of anodic oxidation of triphenylphosphine in the presence of camphene carried out in acetonitrile with sodium perchlorate as supporting electrolyte has been studied. The major product, triphenylphosphine oxide, has been isolated from the solution in the form of cocrystals of free triphenylphosphine oxide and its complex with sodium perchlorate. The molecular structure of the cocrystals has been studied by X-ray diffraction analysis. Triphenylcamphenylphosphonium perchlorate, bornylacetamide, and a terpene compound with triphenylphosphonium and acetamide substituents in the cycle have been detected by NMR ¹³C as the electrolysis side products.

     

Oxidimetric determination of triphenylphosphine

A method for the determination of triphenylphosphine based on its oxidation to phosphine oxide by iodine or chloramine-T in acid medium in presence of benzene or carbon tetrachloride is described. The oxidation is completed within 2 min and the analytical values are accurate to within 0.5%. The method is applicable to determination of triphenylphosphine in its metal complexes.