• Title/Summary/Keyword: Secondary alcohols

Search Result 48, Processing Time 0.028 seconds

Convenient Synthesies of Carboxylic Esters and Thiol Esters Using Acid Chlorides and Zinc Chloride

  • Kim, Sung-Gak;Lee, Won-Jae;Lee, Jae-ln
    • Bulletin of the Korean Chemical Society
    • /
    • v.5 no.5
    • /
    • pp.187-190
    • /
    • 1984
  • Reaction of acid chlorides with primary alcohols, secondary alcohols, and aryl alcohols in the presence of a catalytic amount of zinc chloride gave the corresponding esters in high yields, whereas the reaction with tertiary alcohols failed to give the esters due to the fast solvolytic reactions of tertiary alcohols with hydrogen chloride generated from the reaction. The use of molecular sieves as a scavenger for hydrogen chloride was found to be moderately effective in the reaction of mesitoyl chloride with tertiary alcohols. Reaction of acid chlorides with thiols in the presence of zinc chloride in acetonitrile proceeded cleanly, yielding the corresponding thiol esters in high yields.

Allyl Alcohol Found in Heated Garlic is a Potent Selective Inhibitor of Yeasts

  • Lee Se-Hi;Woo Yong-Ho;Kyung Kyu-Hang
    • Journal of Microbiology and Biotechnology
    • /
    • v.16 no.8
    • /
    • pp.1236-1239
    • /
    • 2006
  • Allyl alcohol (2-propen-l-ol), found in considerable amounts in heated garlic, was able to discriminate yeasts from bacteria and was approximately three orders of magnitude more inhibitory towards yeasts than bacteria. The average minimum inhibitory concentration (MIC) of allyl alcohol for bacteria and yeasts was 5.0% and 0.0056%, respectively. The unsaturated primary alcohols, including allyl alcohol and 2-buten-l-ol, seemed to work differently from all the other saturated alcohols and unsaturated secondary alcohols in inhibiting various yeasts. An alcohol dehydrogenase-negative (ADH$^-$) strain of Saccharomyces cerevisiae was as resistant to allyl alcohol as various bacteria, exhibiting an MIC of 5.0%. The unsaturated primary alcohols were apparently oxidized into the corresponding unsaturated aldehydes before they inhibited the yeasts.

Chemoselective Iodination of Alcohols with CeCl3·7H2O/NaI over SiO2 under Microwave Irradiation

  • Hosseinzadeh, Rahman;Tajbakhsh, Mahmood;Lasemi, Zahra;Sharifi, Ali
    • Bulletin of the Korean Chemical Society
    • /
    • v.25 no.8
    • /
    • pp.1143-1146
    • /
    • 2004
  • A simple and effective procedure for conversion of primary, secondary, allylic and benzylic alcohols into the corresponding iodides is described using $CeCl_3{\cdot}7H_2O/NaI\;over\;SiO_2$ under microwave irradiation. Benzylic alcohols are selectively converted in the presence of saturated alcohols into their corresponding benzylic iodides under these conditions.

Purification and Characterization of NAD-Dependent n-Butanol Dehydrogenase from Solvent-Tolerant n-Butanol-Degrading Enterobacter sp. VKGH12

  • Veeranagouda, Y.;Benndorf, Dirk;Heipieper, Hermann J.;Karegoudar, T.B.
    • Journal of Microbiology and Biotechnology
    • /
    • v.18 no.4
    • /
    • pp.663-669
    • /
    • 2008
  • The solvent-tolerant bacterium Enterobacter sp. VKGH12 is capable of utilizing n-butanol and contains an $NAD^+$-dependent n-butanol dehydrogenase (BDH). The BDH from n-butanol-grown Enterobacter sp. was purified from a cell-free extract (soluble fraction) to near homogeneity using a 3-step procedure. The BDH was purified 15.37-fold with a recovery of only 10.51, and the molecular mass estimated to be 38 kDa. The apparent Michaelis-Menten constant ($K_m$) for the BDH was found to be 4 mM with respect to n-butanol. The BDH also had a broad range of substrate specificity, including primary alcohols, secondary alcohols, and aromatic alcohols, and exhibited an optimal activity at pH 9.0 and $40^{\circ}C$. Among the metal ions studied, $Mg^{2+}$ and $Mn^{2+}$ had no effect, whereas $Cu^{2+},\;Zn^{2+}$, and $Fe^{2+}$ at 1 mM completely inhibited the BDH activity. The BDH activity was not inhibited by PMSF, suggesting that serine is not involved in the catalytic site. The known metal ion chelator EDTA had no effect on the BDH activity. Thus, in addition to its physiological significance, some features of the enzyme, such as its activity at an alkaline pH and broad range of substrate specificity, including primary and secondary alcohols, are attractive for application to the enzymatic conversion of alcohols.

The Positional Effect of Solute Functional Group among Positional Isomers of Phenylpropanol in Hydroxyl Group-Solvent Specific Interactions in Methanol/Water Mixed Solvents Monitored by HPLC

  • Cheong, Won-Jo;Ko, Joung-Ho;Kang, Gyoung-Won
    • Bulletin of the Korean Chemical Society
    • /
    • v.26 no.8
    • /
    • pp.1246-1250
    • /
    • 2005
  • We have evaluated the hydroxyl group-solvent specific interactions by using a Lichrosorb RP18 stationary phase and by measuring the retention data of carefully selected solutes in 50/50, 60/40, 70/30, 80/20, and 90/10(v/v%) methanol/water eluents at 25, 30, 35, 40, 45, and 50 ${^{\circ}C}$. The selected solutes are 3 positional isomers of phenylpropanol, that is, 1-phenyl-1-propanol, 1-phenyl-2-propanol, and 3-phenyl-1-propanol. There exist clear discrepancies in ${\Delta}H^o$ (solute transfer enthalpy from the mobile to the stationary phase) and $T{\Delta}S^o$ (solute transfer entropy) among positional isomers. The difference in ${\Delta}H^o$ and $T{\Delta}S^o$ between secondary alcohols (1-phenyl-1-propanol and 1-phenyl-2-propanol)is negligible compared to the difference between the primary alcohol (1-phenyl-3-propanol) and secondary alcohols. The $T{\Delta}S^o$ values of 3-phenyl-1-propanol are close to those of butylbenzene while the $T{\Delta}S^o$ values of secondary alcohols are close to those of propylbenzene. The difference in ${\Delta}{\Delta}H^o$ (specific solute-mobile phase interaction enthalpy) between the primary alcohol and the secondary alcohol decreases with increase of methanol content in the mobile phase. A unique observation is an extremum for 1-phenyl-3-propanol in the plot of $T{\Delta}{\Delta}S^o$ vs. methanol volume %. The positive sign of $T{\Delta}{\Delta}S^o$ of 3-phenyl-1-propanol implies that the entropy of 3-phenyl-1-propanol is greater than that of the hypothetical alkylbenzene (the same size and shape as phenylpropanol) in the mobile phase.

PVT Relations of Associating Fluids using the Cubic-Plus-Association EoS (CPA 상태방정식에 의한 회합성 유체의 PVT 관계)

  • Kim, Mi-Kyoung;Shim, Min-Young;Kim, Ki-Chang
    • Journal of Industrial Technology
    • /
    • v.20 no.A
    • /
    • pp.195-202
    • /
    • 2000
  • For modeling an equation of state suitable for describing associating fluids, we combined the cubic equation of state (Peng-Robinson) and an association term of SAFT. The resulting EoS (Cubic-Plus-Association) is not cubic with respect to volume and contains five pure compound parameters. Excellent correlations of both vapour pressures and saturated liquid volumes were obtained for n-alcohols and secondary alcohols. We considered a method for reducing the number of adjustable pure compound parameters from five to three, and the resulting 3-parameters EoS relation maintained the good correlation of vapour pressures and saturated liquid volumes.

  • PDF