• Title/Summary/Keyword: Benzyl Alcohol

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Oxidation of Benzyl Alcohols with Extraordinarily High Kinetic Isotope Effects

  • Jo, Myeong-Ran;Seok, Won-K.
    • Bulletin of the Korean Chemical Society
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    • v.32 no.spc8
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    • pp.3003-3008
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    • 2011
  • Reactions of benzyl alcohol and its derivatives by [Ru$^{IV}$(tpy)(dcbpy)(O)]$^{2+}$ (tpy = 2,2':6',2"-terpyridine; dcbpy = 4,4'-dicarboxy-2,2'-bipyridine) leading to the corresponding benzaldehydes in acetonitrile and water have been studied. Kinetic studies show that the reaction is first-order in both alcohol and oxidant, with k = 1.65 (${\pm}$ 0.1) $M^{-1}s^{-1}$ at $20^{\circ}C$, ${\Delta}H^{\ddag}$ = 4.3 (${\pm}$ 0.1) kcal/mol, ${\Delta}S^{\ddag}$ = -22 (${\pm}$ 1) eu, and $E_a$ = 4.9 (${\pm}$ 0.1) kcal/mol. High ${\alpha}$ C-H kinetic isotope effects are observed, but O-H solvent isotope effects are negligible. Spectral evidences with the isotope effects suggest that oxidation of benzyl alcohols occurs by a two-electron, hydride transfer. The catalytic cycles of aerobic benzyl alcohol oxidation are employed.

Enzymatic synthesis of benzyl alcohol galactoside using Escherichia coli β-galactosidase (대장균 β-galactosidase를 이용한 benzyl alcohol galactoside의 합성 연구)

  • Jung, Kyung-Hwan
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.2
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    • pp.572-580
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    • 2019
  • Recently, it has been reported that benzyl alcohol (BzOH) as an additive in cosmetics, food, and medicine lead to toxicity and allergy problem. Then, to circumvent this hurdle, we carried out the synthesis of benzyl alcohol galactoside (BzO-gal). Previously, it was confirmed that BzO-gal was synthesized by transgalactosylation reaction using Escherichia coli (E. coli) ${\beta}$-galactosidase (${\beta}-gal$). Meanwhile, in this study, two peaks of BzO-gal as sodium adduct ion (m/z=293.1004) and protonated ion (m/z=271.1180) were detected in the reaction mixture by liquid chromatography/electrospray ionization mass spectrometry (LC/ESI-MS). In addition, the amount of ${\beta}-gal$ and BzOH concentration, temperature, pH, and lactose concentration, respectively, were optimized (${\beta}-gal$, 0.75 U/mL; BzOH, 185 mM; temperature, $40^{\circ}C$, pH, 7.5; lactose, 350 g/l). Under these optimal conditions, 185 mM BzOH was converted into about 131 mM BzO-gal, in which the conversion yield was about 72%. In the future, BzO-gal will be applicable as a substitute for BzOH as a less toxic preservative for the cosmetic, pharmaceutical, and food industries, and we are planning to investigate the characteristics of BzO-gal as a preservative.

Preparation of Ag/TiO2 Particle for Aerobic Benzyl Alcohol Oxidation (Aerobic Benzyl Alcohol Oxidation 반응용 Ag/TiO2 제조)

  • Kim, Chang-Soo;Yoo, Kye Sang
    • Applied Chemistry for Engineering
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    • v.24 no.6
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    • pp.663-667
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    • 2013
  • $Ag/TiO_2$ particle was prepared using various ionic liquids by wet impregnation. The properties of the particles were significantly affected by the composition of ionic liquids. This is mainly attributed to different abilities of an ionic liquid to coordinate with the silver particle, leading to various coagulation of silver particles. The catalytic activity of the prepared samples was examined for the aerobic benzyl alcohol oxidation. Among the particles, $Ag/TiO_2$ prepared with 1-octyl-3-methylimidazolium tetrafluoroborate showed the best catalytic performance.

Electrochemical Synthesis of 𝛽-Hydroxynitrile by addition of Acetonitrile into Benzyl Alcohol (벤질알코올과 아세토나이트릴의 반응을 통한 𝛽-hydroxynitrile의 전기화학적 합성)

  • Choi, Hyebin;An, Jaun;Kwon, Ki-Young
    • Applied Chemistry for Engineering
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    • v.33 no.4
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    • pp.436-439
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    • 2022
  • 𝛽-Hydroxynitrile and 𝛽-ketonitrile were synthesized by the electrochemical oxidation of benzyl alcohol in an acetonitrile solvent. 𝛽-Hydroxynitrile was prepared by the reaction between benzaldehyde from the oxidation of benzyl alcohol and acetonitrile anion which was produced from the electrochemical reduction of acetonitrile. 𝛽-Hydroxynitrile was finally electrochemically converted into 𝛽-ketonitrile by applying 20 mA of current for 3 h. We demonstrated that 𝛽-hydroxynitrile or 𝛽-ketonitrile syntheses were prepared by electrochemical oxidation of benzyl alcohol with a commonly used Pt electrode at room temperature.

The Effect of Organic Solvent in the Dyeing of Silk Fiber (견섬유의 염색에 있어서 첨가용제의 영향( I ))

  • 황성민;윤남식;임용진;이동수;이인전
    • Textile Coloration and Finishing
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    • v.1 no.1
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    • pp.47-53
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    • 1989
  • The effect of organic solvent in the dyeing of silk fiber by acid dye was investigated. Acetophenone and benzyl alcohol were shown to be the most effective for the rate of dyeing of silk fiber by Milling Cyanine 5R (C.I. Acid Blue 113), a milling type acid dye, but, with benzyl alcohol, the equilibrium dye uptake was much lower than that in the absence of it. In the presence of solvent, maximum dye uptake shifted to lower temperature than 6$0^{\circ}C$, while without solvent, it was shown at about $60^\circ{C}$. When dyed by Orange II (C.I. acid Orange 7) under same condition equilibrium dye uptake of silk fiber was lower than that for milling type acid dye, and in the presence of benzyl alcohol, still much lower uptake resulted. All these fact reveals that organic solvents in the solvent-assisted dyeing of silk fiber broaden micelle spacings too much, resulting in increased rate of dyeing, and decreased equilibrium dye uptake, contrary to wool.

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Effect of Solvent in the Dyeing System of Acid Dye/Human Hair (산성염료/모발 염색계에 있어서 용매의 효과)

  • Lee, Jin;Lim, Sun-Nye;Jung, Nam-Young;Lee, Woong-Eui;Choi, Chang-Nam
    • Textile Coloration and Finishing
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    • v.23 no.4
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    • pp.250-256
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    • 2011
  • In this work, the effects of surfactant and solvents, such as benzyl alcohol and n-propyl alcohol, on the human hair dyeing with acid dye was investigated including the amount of dyes in hair according to dyeing time, temperature, and pH. And the damage of dyed hair was assessed by water retention, protein release, and SEM images of the dyed hairs. By adding benzyl alcohol in acid dyeing, the dyeing rate was increased and the dyeing equilibrium was established at early stage. The water retention of the dyed hair was increased and the protein release of the dyed hair was decreased. Therefore the hair was damaged less during the dyeing.

Kinetic Study on the Oxidation Reaction of Alcohols by Cr(VI)-Quinoline Compound (크롬(VI)-퀴놀린 화합물에 의한 알코올류의 산화반응에 대한 반응속도론적 연구)

  • Park, Young-Cho;Kim, Soo-Jong
    • Journal of Convergence for Information Technology
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    • v.11 no.9
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    • pp.109-114
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    • 2021
  • Cr(VI)-quinoline compound[(C9H7NH)2Cr2O7] was synthesized by the reaction between of quinoline and chromium(VI) trioxide, and structure was FT-IR, elemental analysis. The oxidation ability of benzyl alcohol greatly depends upon the dielectric constant of the used organic solvent, where carbon tetrachloride was worst and N,N'-dimethylformamide was best solvent. Noticeably, in N,N'-dimethylformamide solvent, Cr(VI)-quinoline compound oxidized substituted benzyl alcohols. The Hammett reaction constant(ρ)=-0.69(303K). As a resuit, Cr(VI)-quinoline compound was found as efficicent oxidizing agent that converted benzyl alcohol, allyl alcohol, primary alcohol and secondary alcohols to the corresponding aldehydes or ketones. Cr(VI)-quinoline compound was selective oxidizing agent of benzyl alcohol, allyl alcohol and primary alcohol in the presence of secondary alcohol ones.

Synthesis of Ru Incorporated TiO2 and Application to Oxidation of Benzyl Alcohol with Molecular Oxygen (Ru를 도입한 TiO2의 합성과 산소를 이용한 알코올 산화반응 연구)

  • Kim, Youngyeong;Choi, Myong Yong;Kwon, Ki-Young
    • Applied Chemistry for Engineering
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    • v.25 no.6
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    • pp.645-647
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    • 2014
  • We synthesized $TiO_2$ ($Ru_x/TiO_2$) incorporating $TiO_2$ and Ru via an one-step hydrothermal method. The physical properties were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). The prepared samples were applied as a catalyst for the oxidation of benzyl alcohol to benzaldehyde using molecular oxygen ($O_2$). Especially, the catalytic activities increased as the contents of ruthenium in $TiO_2$ increased without the formation of any byproducts.