Synthesis of polymers containing tertiary phosphine oxides using complex bases

Tertiary phosphine oxides have been prepared in excellent yield from primary alkyl halides or aromatic halides and activated sodium phosphinates obtained by reaction of dialkyl phosphine oxides with complex bases (NaNH₂/tBuONa). This reaction has been successfully applied to soluble and cross-linked bromopolystyrenes and to macroporous polystyrenes with bromooctyl substituents giving polymers which contain pendant phosphine oxide groups.     

Reduction of tertiary phosphine oxides with DIBAL-H

The reduction of tertiary phosphine oxides (TPOs) and sulfides with diisobutylaluminum hydride (DIBAL-H) has been studied in detail. An extensive solvent screen has revealed that hindered aliphatic ethers, such as MTBE, are optimum for this reaction at ambient temperature. Many TPOs undergo considerable reduction at ambient temperature and then stall due to inhibition. 31P and 13C NMR studies using isotopically labeled substrates as well as competition studies have revealed that the source of this inhibition is tetraisobutyldialuminoxane (TIBAO), which builds up as the reaction proceeds. TIBAO selectively coordinates the TPO starting material, preventing further reduction. Several strategies have been found to circumvent this inhibition and obtain full conversion with this extremely inexpensive reducing agent for the first time. Practical reduction protocols for these critical targets have been developed.     

Thermal properties of poly(tertiary phosphine oxides)

DTA and TGA (in air and in nitrogen) are presented for the poly(tertiary phosphine oxides), C₆H₅[(C₆H₅)P(O)CH₂CH₂]_nP(O)(C₆H₅)₂, where n = 1, 2, or 3.     

Metal-free reduction of tertiary phosphine oxides with Hantzsch ester简

The （COCl）2/Hantzsch ester is found to be an effective system for the metal-free reduction of tertiary phosphine oxides. The reaction proceeds under mild conditions, and is applicable to triarylphosphine oxides and alkyldiarylphosphine oxides to produce the corresponding tertiary phosphines in good to excellent yields. This new finding provides a practical, convenient and metal-free method for the reduction of tertiary phosphine oxides to tertiary phosphines, and shows potential application in organic synthesis.     

Extraction of uranium and plutonium by tertiary aliphatic phosphine oxides

The effect of the structure of the alkyl chain in trialkyl phosphine oxides (TAPO) upon their extractive ability for uranium(VI) and plutonium(IV) in various diluents has been investigated. Solid complex compounds of U(VI) with TAPO have been isolated and characterized by the DTA and infrared spectra measurements.     

Microemulsions with alkyldimethyl phosphine oxides and alkyldiethyl phosphine oxides

Alkyldimethyl phosphine oxides (C n DMPO) as well as alkyldiethyl phosphine oxides (C n DEPO) with chain lengths of n = 10 (decyl), 12 (dodecyl), and 14 (tetradecyl) were synthesized and purified to study how the formation of microemulsions depends on the size of the headgroup and on the length of the alkyl chain. For that purpose, equal amounts of water and n-octane were taken and surfactant was added to solubilize the two solvents. The resulting fish-shaped phase diagrams for C 10DEPO, C 12DEPO, and C 14DEPO show that the longer the hydrophobic chain the more efficient the surfactant. Simultaneously, the extension of the lamellar phase (L alpha) shifts toward lower total mass fractions gamma of the surfactant, i.e., the tendency to form lyotropic liquid crystals (LCs) increases. These trends are well-known for nonionic alkyl ethylene oxides and can thus be interpreted accordingly. What is astonishing, however, is the significant influence the size of the short side chains has. Replacing two methyl groups by two ethyl groups leads to a drastic drop of the three-phase region toward lower temperatures, while the efficiency remains nearly unchanged. Moreover, the tendency to form LCs decreases significantly.     

(3,5-Diallylisocyanuratomethyl)phosphine oxides and some of their properties

Reaction of sodium diallylisocyanurate with tris(chloromethyl)-, bis(chloromethyl)phenyl-, and (chloromethyl)diphenylphosphine oxides yields, depending on the stoichiometric ratio of the reagents, mono-, bis-, and tris(3,5-diallylisocyanuratomethyl)phosphine oxides.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Science Center, Russian Academy of Sciences, 420083 Kazan, Tatarstan, Russia. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2773–2777, December, 1992.     

Solvent extraction of some transition elements with sulphoxides and phosphine oxides

Transition elements are known to form anionic chloro complexes and some are efficiently extracted by tributyl phosphate (TBP) from hydrochloric acid medium. In this paper an attempt is made to compare the solvent extraction characteristics of di-n-butyl sulphoxide (DBSO) with TBP in respect of extraction of Cr(VI), Mn(II), Fe(III), Co(II), Cu(II), Zn(II) and Zr(IV) from HCl solutions. The effects of the organic group on the extraction behaviour has been studied by exploring the extraction of Fe(III) by diphenyl sulphoxide (DPSO) and triphenyl phosphine oxide (TPPO). Possible explanations for the extraction in terms of donor-acceptor interaction have been discussed.     

Quaternary ammonium salts as alkylating agents in the synthesis of tertiary phosphine oxides

A procedure was developed for the synthesis of tertiary phosphine oxides by alkylation of secondary phosphine oxides with quaternary ammonium salts. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 390–392, February, 1999     

The preparation and properties of some tertiary phosphine and phosphine chalcogenide adducts of BI3 and BBr3

The adducts of BI3 and BBr3 with various tertiary phosphines and their chalcogenide derivatives are described. The proton and boron-11 NMR spectra of many of these compounds are reported for the first time. Although the methyl proton-phosphorus-31 coupling constants are nearly identical in the (CH₃)₃PBX₃ (X = F, Cl, Br, I) series, the boron-phosphorus coupling constant, J_BP, is anomalously low for (CH₃)₃PBI₃ (116 Hz) relative to other members of the series. The phosphine adducts of BBr₃ and BI₃ are white, air and water insensitive solids, whereas the phosphine chalcogenide adducts are quite moisture sensitive. The BI₃ adducts with phosphine chalcogenides lose iodine fairly readily to form intractable material.     

Electron impact induced fragmentations and rearrangements of some phenyl substituted phosphine oxides

Electron impact induced fragmentations and rearrangements of 1-phenyl-2,2,3-trimethylphosphetane 1-oxide, 1-phenylphospholane 1-oxide and 1-phenylphosphorinane 1-oxide were investigated. A process common to all of these phosphine oxides was electron impact induced formation of new carbon-carbon bonds involving the phenyl rings. Evidence for such rearrangements included observation of hydrocarbon fragment ions containing seven or more carbons.     

Organometallic polymers. I. Synthesis of ferrocene-containing poly(phosphine oxides) and poly(phosphine sulfides)

Poly(phosphine oxides) and poly(phosphine sulfides) of ferrocene were synthesized in the melt phase. The resulting ferrocene polymers, linked by phosphorus bridges, were thermally stable and infusible solids, of low molecular weight (M?_n < 4000). Phenyldichlorophosphine, phenyldichlorophosphonate, and phenylphosphonothioic dichloride were copolymerized with ferrocene in the melt phase (80–110°C.) with ZnCl₂ as a catalyst. As the polymerization temperature was raised, cleavage of cyclopentadiene rings from iron became more pronounced, and cyclopentane-bridged polymers of ferrocene were produced in competition with the ferrocene–phosphorus polymers. The cleavage-polymerization process became predominant at 140°C. The structures of poly(phosphine oxides) (and sulfides) of ferrocene were verified by infrared and nuclear magnetic resonance spectroscopy.     

General and selective copper-catalyzed reduction of tertiary and secondary phosphine oxides: convenient synthesis of phosphines

Novel catalytic reductions of tertiary and secondary phosphine oxides to phosphines have been developed. Using tetramethyldisiloxane (TMDS) as a mild reducing agent in the presence of copper complexes, PO bonds are selectively reduced in the presence of other reducible functional groups (FGs) such as ketones, esters, and olefins. Based on this transformation, an efficient one pot reduction/phosphination domino sequence allows for the synthesis of a variety of functionalized aromatic and aliphatic phosphines in good yields.     

Flame-retardant properties of epoxide and unsaturated polyester resins modified with tertiary phosphine oxides containing chlorinated phenoxy groups

The flame-retardant properties of the epoxide resin “Epoxa AP-2” and the unsaturated polyester resin “Vinalkid 550P” modified with dimethyl(2,4,6-trichlorophenoxymethyl)phosphine oxide (DMPO), methyl-bis(pentachlorophenoxymethyl)phosphine oxide (MBPO) and tris(2,4,6-trichlorophenoxymethyl)phosphine oxide are examined. It is established that all three products are effective fire-retardants for epoxide as well as for unsaturated polyester resins. The effect is notable at about 10–15% presence. The oxygen indexes, determined by the ASTM-D-2863 method, show an increase of several units in comparison with the unmodified resins. The fire-retardant action of DMPO, MBPO and TTPO is significantly enhanced by the addition of Sb₂O₃.