• Title/Summary/Keyword: triphenylphosphine

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Homogeneous Catalysis (VI). Hydride Route with Chloro Ligand Dissociation for the Hydrogenation of Acrylonitrile with trans-Chlorocarbonylbis(triphenylphosphine)iridium(I)

  • Moon, Chi-Jang;Chin, Chong-Shik
    • Bulletin of the Korean Chemical Society
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    • v.4 no.4
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    • pp.180-183
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    • 1983
  • The reaction of $IrClH_2(CO)(Ph_3P)_2$ ($Ph_3P$=triphenylphosphine) with acrylonitrile (AN) produces a stoichiometric amount of propionitrile (PN) at $100^{\circ}C$ under nitrogen, which suggests that the catalytic hydrogenation of AN to PN with $IrCl(CO)(Ph_3P)_2$ proceeds through the hydride route where the formation of the dihydrido complex, $IrClH_2(CO)(Ph_3P)_2$ is the initial step. The rate of the hydrogenation of AN to PN with $IrCl(CO)(Ph_3P)_2$ is decreased by the presence of excess $Cl^-$ in the reaction system, which suggests that $Cl^-$ is the dissociating ligand in the catalytic cycle. It has been also found that the rate of the hydrogenation increases with inercase both in hydrogen pressure and in concentration of free $Ph_3P$, and with decrease in AN concentration in the reaction system.

Preparation, Reactions and Catalytic Activities of Water Soluble Iridium-Sulfonated Triphenylphosphine Complex

  • 진종식;장원태;양서균;주광석
    • Bulletin of the Korean Chemical Society
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    • v.18 no.3
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    • pp.324-327
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    • 1997
  • Water soluble iridium complex, IrCl(CO)(TPPTS)2·χH2O (1) (TPPTS=m-trisulfonated triphenylphosphine) has been prepared from the reaction of a water soluble complex, IrCl(COD)(TPPTS)2·6H2O (COD=l,5-cyclooctadiene) with CO and unambiguously characterized by electronic absorption, 31P NMR, 13C NMR and IR spectral data. Complex 1 catalyzes the hydration of terminal alkynes to give ketones in aqueous solutions at room temperature. The rate of PhC≡CH hydration dramatically increases with addition of MeOH to the reaction mixture in H2O, which is understood in terms of i) the excellent miscibility between H2O and MeOH and ii) the assumed catalytic hydration pathway involving the initial formation of (alkyne)IrCl(CO)(TPPTS)2.

Studies on the Desulfurization of 1,3,4-Oxathiazol-2-one and 1,2,4-Dithiazol-3-one with Trivalent Phosphorus Compounds (1,3,4-옥사티아졸-2-온과 1,2,4-디티아졸-3-온의 3가인 화합물과의 탈황반응에 관한 연구)

  • Dong Young Oh;Chung Ryeol Kim
    • Journal of the Korean Chemical Society
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    • v.27 no.5
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    • pp.368-375
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    • 1983
  • The reactions of various 5-aryl-1,3,4-oxathiazol-2-ones with triethylphosphite resulted in the formation of the corresponding benzonitriles and ethylphosphorothioate by desulfurization reaction in 66∼94% yields. 5-(4-Nitrophenyl)-1,3,4-oxathiazol-2-one was also reacted with trimethylphosphite, triethylphosphine, and triphenylphosphine to give 4-nitrobenzonitrile. But it did not react with triphenylphosphate. The reactions of 5-(4-bromophenyl)-1,2,4-dithiazol-3-one with triphenylphosphine resulted in the formation of 4-bromothiobenzoyl isocyanate and triphenylphosphine thioxide. The thioacyl isocyanate was fragmented into nitrile in ether but was stable in chloroform. This desulfurization reaction observed in each reaction may proceed by the intramolecular rearrangement after insertion of the phosphorus compound into the ring. The stable thioacyl isocyanate in chloroform reacted with imine to give 1,3,5-thiadiazin-4-one via 1,4-cycloaddition reaction.

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Synthesis of 1, 1-Diheteroaryl Ethylenes by a Tandem Appel's Dehydration/Thermal Rearrangement Methodology

  • 이기정;허 열;전종갑
    • Bulletin of the Korean Chemical Society
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    • v.20 no.3
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    • pp.341-344
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    • 1999
  • The hydrazones of 2-acetylfuran, 2-acetylthiophene, and 2-acetylpyrrole, were allowed to react with S-methylthioacetimidate hydroiodide (8) to give azinoureas 10, and the reaction of 10 with Appel's dehydration conditions (triphenylphosphine/carbon tetrachloride/triethylamine) led to the corresponding azinocarbodiimides 11, which underwent thermal rearrangement under the reaction conditions to give 1,1-diheteroaryl ethylenes 13.