- Selective Substitution of POCl 3 with Organometallic Reagents: Synthesis of Phosphinates and Phosphonates
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The selectivity of the substitution reaction of phosphoryl chloride with organometallic reagents was investigated using NMR spectroscopy. This led to the discovery that the selectivity of the substitution reaction can be tuned by choosing a proper organometallic reagent. A phosphinate could be obtained by using a Grignard reagent whereas an organozinc reagent provided a phosphonate. Based on these results, one-pot synthetic methods for the preparation of phosphinates and phosphonates using commercially available starting materials were developed. Both methods allow the synthesis of a broad range of either phosphinate or phosphonate derivatives in a straightforward and general procedure. Moreover, using these one-pot procedures, mixed systems substituted with different alkyl/aryl groups can be prepared.
- Verbelen, Bram,Dehaen, Wim,Binnemans, Koen
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p. 2019 - 2026
(2018/04/14)
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- Method of synthesizing alkyl phosphate
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The invention relates to a method of synthesizing alkyl phosphate. The method includes: in the process of synthesizing alkyl phosphate, using inert substance to mix with reactant alcohol; dropwise adding phosphorus oxychloride at low temperature, allowing reaction at normal temperature for a period of time, and rising temperature for reaction; using alkali for neutralizing, washing with water, and distilling to remove low-boiling-point solvent and reactant; depressurizing and distilling to obtain high-purity alkyl phosphate. Due to existence of the third inert substance, reaction is enabled to be milder, and high yield is realized; a lot of generated hydrogen chloride is removed in a gaseous mode, so that alkali consumption is reduced and production cost is lowered.
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Paragraph 0050; 0051
(2017/01/02)
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- Oxidizing alkoxylation of phosphine in alcoholic solutions of iodine
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Oxidizing alkoxylation of PH3 to trialkyl phosphates was performed in pyridine-alcoholic solutions of iodine. The optimal conditions of the reaction were found.
- Polimbetova,Borangazieva
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p. 2079 - 2082
(2007/10/03)
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- Oxidative P-O and P-C Coupling of Butanol with Phosphine in the Presence of Oxidizers and Platinum(IV) and Platinum(II)
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A butanol solution of Na2PtCl6 at 60-80°C in the presence of p-benzoquinone or NaBrO3 is found to rapidly consume even traces of PH3 until complete reduction of benzoquinone to hydroquinone or NaBrO3 to NaBr, respectively. The nature of products depends on the valence state of platinum and the nature of the oxidizer. Without an oxidizer, platinum(IV) is reduced to platinum(II) with formation of tributyl phosphate, the product of P-O coupling of PH3 with BuOH, while platinum(II) is reduced to platinum(0) with formation of butylbis(α-hydroxybutyl)phosphine oxide Bu(α-PrCHOH)2PO, the product of P-C coupling of PH3 with BuOH. In the presence of benzoquinone, which oxidizes Pt(0) to Pt(II), a P-C bond is formed, while in the presence of sodium bromate, which regenerates Pt(II) to Pt(IV), P-O coupling of PH3 with BuOH occurs. The products and principal steps of this new reaction were studied by the methods kinetics, red-ox potentiometry, chemical modeling, inhibition of free-radical reactions, 31P NMR, IR and X-ray photoelectron spectroscopy, X-ray spectral microanalysis, and gas-liquid chromatography. We showed that the P-C coupling of PH3 with BuOH is promoted by platinum(II) complex, while P-O coupling is promoted by platinum(IV) complex. In the key steps the Pt(II) butoxyphosphide complex PtCl3(OBu)(PH2)- arises from reaction of the Pt(II) phosphide complex with platinum(IV). The red-ox decomposition of intermediate complexes leads to formation of phosphinite (BuO)2PH2 and Pt(II), or (α-hydroxybutyl)phosphine and Pt(0). The catalytic cycles are completed by fast steps of oxidative butoxylation of (BuO)PH2 to (BuO)3PO or by α-hydroxybutylation of (PrCHOH)PH2 to Bu(PrCHOH)2PO, and oxidation of Pt(II) to Pt(IV) with bromate or Pt(0) to Pt(II) with benzoquinone, respectively.
- Dorfman,Polimbetova,Aibasov
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p. 231 - 247
(2007/10/03)
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- PREPARATION OF ALKYLDIHYDROXYALKYLPHOSPHINE OXIDES AND TRIALKYL PHOSPHATES FROM PHOSPHINE AND ALCOHOLS IN THE PRESENCE OF PLATINUM(IV) HALIDES
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31P NMR spectroscopy, gas chromatography, and potentiometric methods indicate that an alcoholic solution of Na2PtCl6 rapidly absorbs even traces of PH3 at 373-423 K to give trialkyl phosphates and alkyldihydroxyalkylphosphine oxides, platinum(IV) being reduced to platinum(0). At high temperatures oxidative C-phosphorylation prevails, while at low temperatures O-phosphorylation of alcohols by phosphine dominates. The rate of oxidative C- and O-phosphorylation of alcohol increases with increase in the concentrations of alcohol, phosphine, NaBr, NaI, Pt(IV) and Pt(II) and falls when H2O, HCl, or NaCl are added. Methods of chemical modeling and isolation of intermediate products show that phosphates are formed via stages of oxidation of dialkyl hydrogen phosphites resulting from dealkylation of trialkyl phosphites, while phosphine oxides are formed by isomerization of trihydroxyalkylphosphines.
- Dorfman, Ya. A.,Levina, L. V.,Aibasov, E. Zh.
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p. 1085 - 1092
(2007/10/02)
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- CHLORINATION OF PHOSPHINE IN ALCOHOLS
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Trialkyl phosphates are rapidly and selectively formed when dilute gaseous PH-Ar and Cl2-Ar mixtures are passed into alcohols (ROH, R=Bu, i-Bu, Am, i-Am, Oct) at 50-70 deg C.Analogous results are obtained in the presence of pyridine at 8-25 deg C.The reaction was studied by gas chromatography, 31P NMR spectroscopy, and potentiometry.The reaction was shown to pass successively through the stages of the chlorination of phosphine to PCl5, the alcoholysis of phosphorus pentachloride to phosphoryl chloride, and finally by the esterification of phsophoryl chloride to trialkyl and dialkyl phosphates.Pyridine, excess af alcohol, and high temperature accelerate the stage of the esterification of phosphoryl chloride to the trialkyl phosphate.
- Dorfman, Ya. A.,Polimbetova, G. S.,Aibasov, E. Zh.,Borangazieva, A. K.,Kokpanbaeva, A. O.,Faizova, F. Kh.
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p. 1860 - 1864
(2007/10/02)
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- Preparation of aliphatic phosphates
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A process for the preparation of trialkyl and trialkenyl phosphates. The process involves oxidation of the corresponding phosphite with oxygen or an oxygen-containing gas. The oxidation is catalyzed by a metal catalyst such as a transition metal carboxylate, for example, and is carried out at relatively low temperatures.
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