• Title/Summary/Keyword: 1,2-Diketones

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Palladium Catalyzed Carbonylative Vinylation of Aryl Halides with Olefins and Carbon Monoxide

  • Kim, Jin-Il;Ryu, Cheol-Mo
    • Bulletin of the Korean Chemical Society
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    • v.8 no.4
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    • pp.246-250
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    • 1987
  • The reaction of aryl iodides or bromides with olefins in the presence of 1 mol % of $PdCl_2(PPh_3)_2$ and 3 equiv. of $n-Bu_3N\; at\; 100^{\circ}C$ in carbon monoxide atmosphere gave the corresponding aryl vinyl ketones in good yields with small amount of vinylated 1-aryl olefins. But, when the reaction was proceeded under the 10 atm of carbon monoxide, aryl vinyl ${\alpha}$-diketones and aryl vinyl ketones were obtained in moderate to good yields. The reaction was tolerant of a wide variety of functional groups on either the aryl halides or olefin compounds. Reactivity of aryl halide decrease in the order; aryl iodide > aryl bromide ${\gg}$aryl chloride. In general, the reaction proceeded well and gave good yields of aryl vinyl ketones and aryl vinyl ${\alpha}$-diketones when reactants are substituted with electron withdrawing groups.

Transition Metal Catalyzed the Double Hydrohydroxymethylation of Carbonyl Compounds by a Carbon Monoxide-Water System (전이금속촉매-일산화탄소-물계에 의한 카르보닐화합물의 이중 히드로히드록시메틸화 반응)

  • Sang Chul Shim;Kyung Eun Min;Keun Tae Huh
    • Journal of the Korean Chemical Society
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    • v.30 no.1
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    • pp.101-104
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    • 1986
  • Dialdehydes such as adipaldehyde, glutaraldehyde, and succinaldehyde were readily reduced to give their corresponding 1,6-hexanediol, 1,5-pentanediol, and 1,4-butanediol in good yields in the presence of catalytic amount of hexarhodium hexadecacarbonyl or iron pentacarbonyl in water and methoxyethanol or ethanol at 180$^{\circ}C$ for 4 hr under carbon monoxide atmosphere. Under the same reaction conditions, diketones such as 2,5-hexanedione, 2,4-pentanedione, and 2,3-butanedione afforded their corresponding 2,5-hexanediol, 2,4-pentanediol and 2,3-butanediol in moderate yields. For double hydrohydroxymethylation of dialdehydes or diketones, rhodium or iron carbonyl complexes are more effective than others. Particularly, benzoquinone gave hydroquinone quantitatively.

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MO Theoretical Studies on 1,5-Sigmatropic Hydrogen Shifts in Systems with Terminal Heteroatoms, O and S (말단 헤테로원자가 산소(O)와 황(S)인계의 1,5-수소원자 이동반응에 관한 MO 이론적 연구)

  • Ho Soon Kim;Ikchoon Lee
    • Journal of the Korean Chemical Society
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    • v.30 no.2
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    • pp.195-200
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    • 1986
  • MO studies have been carried out on 1,5-hydrogen shifts between tautomeric forms (6${\pi}$ system) of ${\beta}$-diketones, ${\beta}$-thioxoketones and ${\beta}$-dithioketones by determining transition state and analyzing structural stability effects on the activation barriers using MNDO method. The barrier was found to increase with the stability of the ground state having greater charge separation and with the increase (less stabilization) in the one electron energy ${\Delta}(2\sum\limits^{occ}{\varepsilon}i)^{\neq}$ in the activation process.

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Study on the Development of CVD Precursors I-Synthesis and Properties of New Titanium β-Diketonates

  • 홍성택;임종태;이중철;Ming Xue;이익모
    • Bulletin of the Korean Chemical Society
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    • v.17 no.7
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    • pp.637-642
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    • 1996
  • Preparation and properties of potential CVD (Chemical Vapor Deposition) precursors for the TiO2, a major component of the perovskite materials such as PT, PLT, PZT, and PLZT were investigated. Reactions between β-diketones and TiMe3, formed in situ failed to produce stable Ti(β-diketonate)3 complexes but a stable purple solid, characterized as (OTi(BPP)2)2 (BPP=1,3-biphenyl-1,3-propanedione) was obtained when BPP was used. Several new Ti(Oi-Pr)2(β-diketonate)2 complexes with aromatic or ring substituents were synthesized by the substitution reaction of Ti(OiPr)4by β-diketones and characterized with 1H NMR, IR, ICP, and TGA. Solid complexes such as Ti(Oi-Pr)2(BAC)2 (BAC=1.-phenyl-2,4-pentanedione), Ti(Oi-Pr)2(BPP)2, Ti(Oi-Pr)2(1-HAN)2 (1-HAN=2-hydroxy-1-acetonaphthone), Ti(Oi-Pr)2(2-HAN)2 (2-HAN=1-hydroxy-2-acetonaphthone), Ti(Oi-Pr)2(ACCP)2 (ACCP=2-acetylcyclopentanone), and Ti(Oi-Pr)2(HBP)2 (HBP=2-hydroxybenzophenone) were found to be stable toward moisture and air. Ti(Oi-Pr)2(ACCP)2 and Ti(Oi-Pr)2(HBP)2 were proved to have lower melting points and higher decomposition temperatures. However, these complexes are thermally stable and pyrolysis under an inert atmosphere resulted in incomplete decomposition. Ti(Oi-Pr)2(DPM)2 (DPM=dipivaloylmethane) and Ti(Oi-Pr)2(HFAA)2 (HFAA=hexafluoroacetylacetone) were sublimed substantially during the thermal decomposition. Pyrolysis mechanism of these complexes are dependent on type of β-diketone but removal of Oi-Pr ligands occurs before the decomposition of β-diketonate ligands.

Synthesis of Quinoxaline Derivatives Using TiO2 Nanoparticles as an Efficient and Recyclable Catalyst

  • Alinezhad, Heshmatollah;Tajbakhsh, Mahmood;Salehian, Fatemeh;Biparva, Pourya
    • Bulletin of the Korean Chemical Society
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    • v.32 no.10
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    • pp.3720-3725
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    • 2011
  • $TiO_2$ nanoparticles were synthesized and characterized by SEM and XRD techniques. The $TiO_2$ nanoparticles were employed as a recyclable, inexpensive and efficient catalyst for the synthesis of substituted quinoxalines in high to excellent yields and in relatively short duration.

Synthetic Studies on Fused Nitrogen-heterocycles from N-Amino-N,N $^\prime$-dihydrodiazinediones (I). Condensation of N-Amino-N,N $^\prime$-dihydrodiazinediones with 1,3-Dicarbonyl Compounds

  • Shin, Sung-Chul;Lee, Youn-Young
    • Bulletin of the Korean Chemical Society
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    • v.9 no.6
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    • pp.359-362
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    • 1988
  • The condensation of 1-amino-1,2-dihydro-3,6-pyridazinedione (1) and 2-amino-2,3-dihydro-1,4-phthalazinedione (2) with 1,3-diketones or 1,3-dialdehydes in polyphosphoric acid gave 6,9-dihydro-6,9-dioxopyridazino [1,2-a][1,2,3]triazines (3-6) and 6,11-dihydro-6,11-dioxo[1,2,3]triazino[1,2-b]phtha lazines (7-10), respectively. The condensation of 2 with 2,4-pentanedione in acetic acid gave N-alkylidene intermediate (11), which was cyclized to 9 by treatment with polyphosphoric acid.