LIQUID-PHASE STEREOSELECTIVE THYMOL HYDROGENATION OVER SUPPORTED NICKEL-CATALYSTS

Citation
Ai. Allakhverdiev et al., LIQUID-PHASE STEREOSELECTIVE THYMOL HYDROGENATION OVER SUPPORTED NICKEL-CATALYSTS, Catalysis letters, 29(1-2), 1994, pp. 57-67
Citations number
27
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry Physical
Journal title
ISSN journal
1011-372X
Volume
29
Issue
1-2
Year of publication
1994
Pages
57 - 67
Database
ISI
SICI code
1011-372X(1994)29:1-2<57:LSTHOS>2.0.ZU;2-H
Abstract
The stereoselective hydrogenation of thymol was studied in liquid phas e over several nickel catalysts, modified by coimpregnation of inorgan ic compounds containing chlorine. The total activity of all catalysts studied was decreased and was on the same order of magnitude, indicati ng that chlorine even after reduction remains on the surface and is re sponsible for the poisoning effects. Such blocking of accessible sites results in similar reaction rates for the catalysts studied. Selectiv ity and stereoselectivity to menthols and menthones changed significan tly. The modifiers could influence the rate of keto-enol transformatio ns, which is thought to be the key selectivity and stereoselectivity g overning step.