• Title/Summary/Keyword: Primary alcohols

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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
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    • v.16 no.8
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    • pp.1236-1239
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    • 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.

Reducing Characteristics of Potassium Tri-sec-butylborohydride

  • Yoon, Nung-Min;Hwang, Young-Soo;Yang, Ho-Seok
    • Bulletin of the Korean Chemical Society
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    • v.10 no.4
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    • pp.382-388
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    • 1989
  • The approximate rates and stoichiometry of the reaction of excess potassium tri-sec-butylborohydride ($K_s-Bu_3BH$) with selected organic compounds containing representative functional groups were determined under the standard conditions (0$^{\circ}C$, THF) in order to define the characteristics of the reagent for selective reductions. Primary alcohols evolve hydrogen in 1 h, but secondary and tertiary alcohols and amines are inert to this reagent. On the other hand, phenols and thiols evolve hydrogen rapidly. Aldehydes and ketones are reduced rapidly and quantitatively to the corresponding alcohols. Reduction of norcamphor gives 99.3% endo- and 0.7% exo-isomer of norboneols. The reagent rapidly reduces cinnamaldehyde to the cinamyl alcohol stage and shows no further uptake of hydride. p-Benzoquinone takes up one hydride rapidly with 0.32 equiv hydrogen evolution and anthraquinone is cleanly reduced to the 9,10-dihydoxyanthracene stage. Carboxylic acids liberate hydrogen rapidly and quantitatively, however further reduction does not occur. Anhydrides utilize 2 equiv of hydride and acyl chlorides are reduced to the corresponding alcohols rapidly. Lactones are reduced to the diol stage rapidly, whereas esters are reduced moderately (3-6 h). Terminal epoxides are rapidly reduced to the more substituted alcohols, but internal epoxides are reduced slowly. Primary and tertiary amides are inert to this reagent and nitriles are reduced very slowly. 1-Nitropropane evolves hydrogen rapidly without reduction and nitrobenzene is reduced to the azoxybenzene stage, whereas azobenzene and azoxybenzene are inert. Cyclohexanone oxime evolves hydrogen without reduction. Phenyl isocyanate utilizes 1 equiv of hydride to proceed to formanilide stage. Pyridine and quinoline are reduced slowly, however pyridine N-oxide takes up 1.5 equiv of hydride in 1 hr. Disulfides are rapidly reduced to the thiol stage, whereas sulfide, sulfoxide, sulfonic acid and sulfone are practically inert to this reagent. Primary alkyl bromide and iodide are reduced rapidly, but primary alkyl chloride, cyclohexyl bromide and cyclohexyl tosylate are reduced slowly.

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
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    • v.5 no.5
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    • pp.187-190
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    • 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.

A Selectivity Character for the Phase Transfer Reactions of Alcohols by Tetra-n-Butyl Ammonium Chloride (Tetra-n-Butyl Ammonium Chloride에 의한 알코올류의 상전이 반응에 대한 선택 특이성)

  • Jee, Jong-Gi;Cboi, Won-Bok;Lee, Kwang-Pill
    • Analytical Science and Technology
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    • v.8 no.1
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    • pp.33-40
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    • 1995
  • Only trace amounts of hydroxide ion can be extracted from aqueous phase into organic phase by Tetra-n-Butyl Ammonium Chloride(TBAC). Addition of small amounts of primary alcohols, particularly certain dials, dramatically changes the behavior of Phase Transfer Catalysis systems, and surprising amounts of base can be found in the organic phase. Quantitative measurements were carried out for the extraction amounts of primary alkoxides, secondary alkoxides, and diol anions into organic phase. On the other hand, the selectivity constants for extraction of primary alcohols and benzylalcohol could be separated to the equilibrium constants of the ion pairs such as $Q^+RO^-$ and $Q^+Cl^-$ in the aqueous and organic phases and this distribution coefficients between phases on anions respectively. In a word, the colligated property for the selectivity of $Q^+RO^-$ in which $Q^+$ is quaternary cation and $RO^-$ alkoxide ion could be discussed in more detail by using of the corresponding free energies to the various constants mentioned.

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Reaction of Lithium Gallium Hydride with Selected Organic Compounds Containing Representative Functional Groups

  • Choe, Jeong Hun;Yun, Mun Yeong;Yun, Jong Hun;Jeong, Dong Won
    • Bulletin of the Korean Chemical Society
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    • v.16 no.5
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    • pp.416-421
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    • 1995
  • The approximate rates and stoichiometry of the reaction of excess lithium gallium hydride with selected organic compounds containing representative functional groups were examined under the standard conditions (diethyl ether, 0 $^{\circ}C)$ in order to compare its reducing characteristics with lithium aluminum hydride and lithium borohydride previously reported, and enlarge the scope of its applicability as a reducing agent. Alcohols, phenol, and amines evolve hydrogen rapidly and quantitatively. However lithium gallium hydride reacts with only one active hydrogen of primary amine. Aldehydes and ketones of diverse structure are rapidly reduced to the corresponding alcohols. Conjugated aldehyde and ketone such as cinnamaldehyde and methyl vinyl ketone are rapidly reduced to the corresponding saturated alcohols. p-Benzoquinone is mainly reduces to hydroquinone. Caproic acid and benzoic acid liberate hydrogen rapidly and quantitatively, but reduction proceeds slowly. The acid chlorides and esters tested are all rapidly reduced to the corresponding alcohols. Alkyl halides and epoxides are reduced rapidly with an uptake of 1 equiv of hydride. Styrene oxide is reduced to give 1-phenylethanol quantitatively. Primary amides are reduced slowly. Benzonitrile consumes 2.0 equiv of hydride rapidly, whereas capronitrile is reduced slowly. Nitro compounds consumed 2.9 equiv of hydride, of which 1.9 equiv is for reduction, whereas azobenzene, and azoxybenzene are inert toward this reagent. Cyclohexanone oxime is reduced consuming 2.0 equiv of hydride for reduction at a moderate rate. Pyridine is inert toward this reagent. Disulfides and sulfoxides are reduced slowly, whereas sulfide, sulfone, and sulfonate are inert under these reaction conditions. Sulfonic acid evolves 1 equiv of hydrogen instantly, but reduction is not proceeded.

Chemical Variability of Leaf Cuticular Waxes According to Leaf Position in Tea Tree

  • Kim, Kwan-Su;Song, Yeon-Sang;Moon, Youn-Ho;Park, Si-Hyung
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.spc1
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    • pp.297-303
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    • 2006
  • Cuticular waxes on tea (Camellia sinensis L.) loaves consisted mainly of alkanes, fatty acids, primary alcohols, triterpenes, and a group of unknown compounds, dominated by primary alcohols and triterpenes. Tea tree accessions used in this study were M-1, M-2, Sakimidori, and Yabukita. For all accessions, the alkane, fatty acid, and primary alcohol constituents consisted of a homologues series, and the major constituents of primary alcohol class were the C28 and C30 homologues. Triterpenes consisted of friedelin, $\beta-amyrin$, and three unidentified ones and friedelin was the most abundant. Leaf area and the total amounts of cuticular waxes per leaf increased with lower leaf position from the apical bud in Yabukita variety. With different leaf position, total wax amount per unit leaf area on the youngest leaves of P1 (the uppermost leaf position) showed the largest amount $(12.80{\mu}g/cm^2)$, and on mature loaves of P2 to P6 ranged from 7.08 to $7.77{\mu}g/cm^2$, and then on the oldest loaves of P7 (the lowest leaf position) remained at an increased level $(17.53{\mu}g/cm^2)$. During leaf development (lower leaf position), the amount of primary alcohols decreased from P1 to P6 and increased at P7, whereas that of triterpenes increased from P1 to P7. The percentage of each wax class in the total wax amount occurred a decrease in primary alcohol and an increase in triterpene, with leaf age.

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
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    • v.25 no.8
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    • pp.1143-1146
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    • 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
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    • v.18 no.4
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    • pp.663-669
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    • 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.

Reducing Characteristics of Potassium Triethylborohydride

  • Yoon, Nung-Min;Yang H.S.;Hwang, Y.S.
    • Bulletin of the Korean Chemical Society
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    • v.8 no.4
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    • pp.285-291
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    • 1987
  • The approximate rates, stoichiometries and products of the reaction of potassium triethylborohydride $(KEt_3BH)$ with selected organic compounds containing representative functional groups under the standard condition $(0^{\circ}C,$ THF) were examined in order to explore the reducing characteristics of this reagent as a selective reducing agent. Primary alcohols, phenols and thiols evolve hydrogen rapidly whereas secondary and tertiary alcohols evolve very slowly. n-Hexylamine is inert to this reagent. Aldehydes and ketones are reduced rapidly and quantitatively to the corresponding alcohols. Reduction of noncamphor gives 3% exo- and 97% endo-norboneol. Anthraquinone is cleanly reduced to 9,10-dihydro-9,10-dihydroxyanthracene stage. Carboxylic acids liberate hydrogen rapidly and quantitatively but further reduction does not occur. Anhydrides utilize 2 equiv of hydride to give an equimolar mixture of acid and alcohol. Acid chlorides, esters and lactones are rapidly and quantitatively reduced to the corresponding alcohols. Epoxides are reduced at moderate rates with Markovnikov ring opening to give the more substituted alcohols. Primary amides liberate 1 equiv of hydrogen rapidly. Further reduction of caproamide is slow whereas benzamide is not reduced. Tertiary amides are reduced slowly. Benzonitrile utilizes 2 equiv of hydride in 3 h to go to the amine stage whereas capronitrile takes only 1 equiv. The reaction of nitro compounds undergo rapidly whereas azobenzene and azoxybenzene are reduced slowly. Cyclohexanone oxime rapidly evolves hydrogen without reduction. Phenyl isocyanate utilizes 1 equiv of hydride to proceed to formanilide stage. Pyridine N-oxide and pyridine is reduced rapidly. Disulfides are rapidly reduced to the thiol stage whereas sulfoxide, sulfonic acid are practically inert to this reagent. Sulfones and cyclohexyl tosylate are slowly reduced. Octyl bromide is reduced rapidly but octyl chloride and cyclohexyl bromide are reduced slowly.