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Cinnamyl Alcohol (cinnamyl + alcohol)

Distribution by Scientific Domains
Chemistry71%

Terms modified by Cinnamyl Alcohol

  • cinnamyl alcohol dehydrogenase
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    Selected Abstracts

    Chiral capillary electrophoresis applied to the determination of phenylglycidol enantiomers obtained from cinnamyl alcohol by asymmetric epoxidation using new titanium(IV) alkoxide compounds as catalysts

    ELECTROPHORESIS, Issue 16 2004
    Sonia Morante-Zarcero
    Abstract A capillary electrophoresis method for the simultaneous determination of phenylglycidol enantiomers in the presence of an excess of cinnamyl alcohol was developed. The effects of the nature, pH and concentration of the buffer, the nature and concentration of chiral selector, the addition of methanol or acetonitrile, and the capillary temperature on the chiral resolution of phenylglycidol enantiomers were studied. Separations were achieved using 20 mM succinylated ,-cyclodextrin dissolved in a 10 mM borate buffer (pH 10.0). Chiral resolution for the phenylglycidol enantiomers in the optimized electrophoretic conditions was higher than 2.0 with an analysis time less than 7 min. The method developed was validated in terms of selectivity, linearity, precision (instrumental repeatability, method repeatability, intermediate precision), the limits of detection and quantitation, and accuracy. Limits of detection of 6.5 mg/L and 8.3 mg/L for (2S,3S)-(,)-3-phenylglycidol ((S,S)-PG) and (2R,3R)-(+)-3-phenylglycidol ((R,R)-PG), respectively, were obtained. The method was applied to study the asymmetric epoxidation of cinnamyl alcohol with titanium(IV) alkoxide compounds as catalysts in order to evaluate their catalytic activity and stereoselectivity of the epoxidation processes. [source]

    Biocatalytic aldehyde reduction using tailor-made whole-cell catalysts: a novel synthesis of the aroma chemical cinnamyl alcohol,

    FLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2007
    Francoise Chamouleau
    Abstract A biocatalytic method for the synthesis of the aroma chemical cinnamyl alcohol by means of a wholecell-catalysed reduction of cinnamyl aldehyde has been developed. As a biocatalyst, recombinant whole cells overexpressing an alcohol dehydrogenase from Lactobacillus kefir and a glucose dehydrogenase from Thermoplasma acidophilum have been used in combination with d- glucose as co-substrate. The reduction process proceeds with a conversion of 98%, even at a high substrate input of 166 g/l cinnamyl aldehyde, and gives a yield of 77% of the desired product, cinnamyl alcohol. In addition to high product concentrations, further advantages of this approach are the use of a low-cost whole-cell catalyst, the high purity of the product, as well as the fact that there is no need for the addition of external co-factor in the biotransformation step. Copyright © 2007 John Wiley & Sons, Ltd. [source]

    Dramatic Pressure Effects on the Selectivity of the Aqueous/Organic Biphasic Hydrogenation of trans -Cinnamaldehyde Catalyzed by Water-Soluble Ru(II)-Tertiary Phosphane Complexes

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1-2 2003
    Gábor Papp
    Abstract In a water/chlorobenzene biphasic reaction, the hydrogenation of trans- cinnamaldehyde, catalyzed by water-soluble Ru(II)-phosphane complexes at pH,3.04 (phosphate buffer), produces a 61:39 mixture of cinnamyl alcohol and dihydrocinnamaldehyde at 1,bar H2; however, the selectivity is increased to 93:7 by increasing the hydrogen pressure to 8,bar. [source]

    Liquid-Phase Hydrogenation of Unsaturated Aldehydes: Enhancing Selectivity of Multiwalled Carbon Nanotube-Supported Catalysts by Thermal Activation

    CHEMCATCHEM, Issue 2 2010
    Bruno
    Abstract Platinum and iridium organometallic precursors are used to prepare nanosized, thermally stable multiwalled carbon nanotube-supported catalysts. The materials are characterized by N2 adsorption at 77,K, temperature-programmed desorption coupled with mass spectrometry, H2 chemisorption, transmission electron microscopy and thermogravimetric analysis; they are tested in the selective hydrogenation of cinnamaldehyde to cinnamyl alcohol under mild conditions (363,K and 1,MPa). A thermal activation at 973,K is found to have a very positive effect over both activity and selectivity, leading to selectivities of approximately 70,%, at 50,% conversion, regardless of the active metal phase (Pt or Ir). Since no noticeable differences in the metal particle sizes are detected, the results are interpreted in light of an enhanced metal/support interaction. This effect, induced by the removal of oxygenated surface groups, is thought to change the adsorption mechanism of the cinnamaldehyde molecule. [source]