Cyclohexene Hydroperoxide Research Articles

Catalytic cyclohexene oxidation in the nano channels of a copper silicate material

Herein we examined the catalytic activity of the copper silicate material SGU-29 for the aerobic partial oxidation of cyclohexene under mild conditions (1 bar of O2 at 70 °C). In particular, the catalytic properties of the active sites provided by [CuO4] square planar units in SGU-29 were investigated for cyclohexene oxidation to generate three main oxidation products (i.e., 2-cyclohexene-1-ol, 2-cyclohexene-1-one, and cyclohexene hydroperoxide). Based on the molecular sieving effect of SGU-29, we especially investigated the intrazeolitic reaction, a catalytic cyclohexene oxidation occurring only in nanochannels of SGU-29. A conversion yield of 42% was obtained for the aerobic cyclohexene oxidation occurring only in SGU-29 nanochannels under 1 bar of O2 at 70 °C for 12 h. We demonstrated unequivocally that catalysis occurred only within the inner channels of SGU-29, rather than on its external surface or within the solvent, and we highlighted the special role of [CuO4] square planar units in catalysis.

Copper metal–organic framework: Structure and activity in the allylic oxidation of cyclohexene with molecular oxygen

Cu-MOF [Cu(bpy)(H 2O) 2(BF 4) 2(bpy)] (bpy: 4,4′-bipyridine) shows promising catalytic activity and high selectivity in allylic oxidation of cyclohexene with molecular oxygen as the only oxidant. Under close to ambient conditions and in the absence of solvent the selectivity in cyclohexene hydroperoxide reached 90%. The combined catalytic, spectroscopic, thermogravimetric, and electron microscopic study indicates that the reaction occurs at the surface of the latent porous framework and both bpy and water are involved in the active complex. Removal of the structural water at 100 °C in vacuum induces a crystal-to-crystal restructuring and opens the pores but eliminates the oxidation activity. Rehydration under ambient conditions in air regenerates Cu-MOF with small structural changes and each dehydration–rehydration cycle increases the oxidation activity. Not only dehydration–rehydration but also stirring the slurry during oxidation induces remarkable changes in the shape and size of the crystallites.

Selective photooxidation of cyclohexene with molecular oxygen sensitized by palladium phthalocyaninesulfonate

Photooxidation of cyclohexene by molecular oxygen was studied in an organic aqueous solution under visible light irradiation, using the title complex PdPcS and its analogues AlPcS and ZnPcS as sensitizer. The reaction gave cyclohexene hydroperoxide as the major product, and 2-cyclohexen-1-one and 2-cyclohexen-1-ol as the minor products. However, the product yield and selectivity, as well as the catalyst stability, were all greatly dependent on the sensitizer, organic solvent, and water concentration present in the mixed solution. Among the three sensitizers examined, PdPcS was the best in terms of both photoactivity and stability. The selectivity of cyclohexene hydroperoxide as high as 99% was obtained with PdPcS in a mixed solvent of CH 3CN and H 2O (85:15, v/v). Quenching experiments with sodium azide and benzoquinone showed that singlet oxygen was involved as the main reactive species responsible for the sensitized oxidation of cyclohexene.

Hydroperoxides form specific antigens in contact allergy

Concomitant positive reactions to colophonium, oxidized limonene, and/or oxidized linalool are recorded in patch test studies. The main allergens in these patch test mixtures are hydroperoxides, which form antigens by a radical pathway. Theoretically, concomitant reactions can be explained not only by concomitant sensitization or by true cross-reactions but also by the hydroperoxides acting as oxidizing agents on skin proteins to form non-specific antigens without hapten-protein binding. The aim of this study was to explore concomitant reactions and cross-reactivity patterns among hydroperoxide haptens. We investigated whether individuals allergic to the main allergen in colophonium, 15-hydroperoxyabietic acid, would also react to limonene hydroperoxide or linalool hydroperoxide. Only 1 of 29 individuals reacted to more than 1 hydroperoxide. The cross-reactivity pattern among cumene hydroperoxide, limonene hydroperoxide, 1-(1-hydroperoxy-1-methylethyl) cyclohexene (cyclohexene hydroperoxide), and 15-hydroperoxydehydroabietic acid was investigated in guinea-pigs. No general cross-reactivity was observed. Cross-reactions between cumene hydroperoxide and cyclohexene hydroperoxide show that similarity in the overall structure and the way of antigen formation are needed. Quantum calculations were used to determine the formation energies of the intermediary radicals. We concluded that hydroperoxides form specific antigens and that formation of non-specific antigens is unlikely. The concomitant patch test reactions described in the literature are best explained as a result of multiple sensitizations.

Zinc phthalocyanine photocatalyzed oxidation of cyclohexene

Cyclohexene photooxidation catalyzed by zinc phthalocyanine (ZnPc) using either red or white light results in the formation of cyclohexenone, cyclohexenol, trans-cyclohexanediol, cyclohexene oxide and cyclohexene hydroperoxide. The product yield increased as follows: cyclohexenone > cyclohexenol > trans-cyclohexanediol > cyclohexene oxide > cyclohexene hydroperoxide. The mechanism for the formation of these products involves both singlet oxygen and radicals (Type II and Type I mechanisms, respectively). The catalyst degraded slowly when low light intensities were employed. The product yields were found to depend on the light intensity, the nature of solvent, irradiation time and the rate of photodegradation of the catalyst.

Preparation and catalytic properties of chitosan bound Schiff base copper complexes

AbstractChitosan, a natural polymer, bound Schiff base copper complexes CT‐She‐Cu, CT‐o‐Bel‐Cu, CT‐m‐Bel‐Cu were prepared and characterize by inductively coupled plasma (ICP), FT‐IR and X‐ray photoelectron spectroscopy (XPS). Their catalytic activity in the oxidation of cyclohexene with molecular oxygen was studied. All the complexes have catalytic activity and the main oxidation products are 2‐cyclohexene‐ol, 2‐cyclohexene‐one and cyclohexene hydroperoxide, which were measured by gas chromatography/mass spectroscopy (GC/MS) and GC/IR. CT‐m‐Bel‐Cu was selected to study the influence of reaction temperature, amount of catalyst and additives such as acid and base on the oxidation of cyclohexene systematically. Copyright © 2004 John Wiley & Sons, Ltd.

Photooxidation of cyclohexene and benzene with oxygen by fullerenes grafted on mesoporous FSM-16

Fullerenes (C60 and C70) are grafted on mesoporous FSM-16 (pore size 2.7 nm), and the grafted fullerenes showed high activities (TON up to 3070 in 9 h) for allylic oxidation of cyclohexene with oxygen in benzene under the irradiation of UV-vis light. In these reactions, phenol is also formed by the oxidation of benzene with cyclohexene hydroperoxide produced in the allylic oxidation of cyclohexene.

Uncatalysed oxidation of cyclohexene

The oxidation products of cyclohexene find several applications as intermediates for the manufacture of useful chemicals like cyclohexanol, cyclohexenol/cyclohexenone, cyclohexadiene, etc. The uncatalysed oxidation of cyclohexene with molecular oxygen was studied in a batch reactor. The products, cyclohexene hydroperoxide, cyclohexenol, cyclohexenone and cyclohexene oxide were realised in the temperature range of 343–393 K. The effect of various kinetic parameters such as temperature, speed of agitation and wall material was studied. The kinetic data were generated at different temperatures and fitted successfully with a rate equation based on autocatalysis by total products. The values of rate constants and activation energy were determined. Recognising the fact that the industrial route to cyclohexene from benzene hydrogenation yields a mixture of cyclohexene and cyclohexane which are difficult to separate, some experiments on oxidation of the mixture of cyclohexene and cyclohexane were also conducted. The values of rate constants remain unchanged in the presence of cyclohexane. The reaction was also studied in an aluminium lined reactor to examine the wall catalytic effect, if any, of the stainless steel wall. The reaction was found to be significantly slower in the aluminium reactor while the selectivity towards the hydroperoxide remained unchanged. The oxidation of cyclohexene represents a unique example of an uncatalysed liquid-phase organic oxidation which can be conducted up to relatively high conversions.

Quantification of carbonyls produced by the decomposition of hydroperoxides

AbstractCarbonyls produced by the decomposition of cyclohexene hydroperoxide and various hydroperoxides of linoleic and linolenic acids and their methyl esters were determined by gas chromatography of the 2,4,6‐trichlorophenylhydrazones. The effect of temperature, iron and copper ions, ethanol and several antioxidants on the rate of decomposition, the nature of the products and their yield was observed. The hydroperoxides of methyl esters decomposed more slowly than those of free fatty acids. Ethanol slowed, and metal ions accelerated the rates of decomposition. Metal ions, especially copper, increased the yield and complexity of the carbonyls formed, but ethanol decreased carbonyl yields.Antioxidants and decomposition temperatures changed the relative yields of carbonyls produced. The 9‐ and 13‐hydroperoxides of linoleic acid gave similar carbonyls, but those of linolenic acid did not. The carbonyl mixtures produced from autoxidized fatty acid methyl esters were more complex than those produced from lipoxygenase‐treated fatty acids.

Oxidative transformations of cyclohexene hydroperoxide catalyzed by penta (dimethylsulfoxido) vanadyl hexathiocyanatoplatinate

Oxidation of cyclohexenyl hydroperoxide by molecular oxygen in the presence of penta(dimethylsulfoxido)vanadyl hexathiocyanatoplatinate proceeds at a high rate at low temperatures with the formation of bifunctional, oxygen-containing products. The main route of the reaction is the molecular oxidation of the hydroperoxide with ring opening in a complex [Catm...HOORn]; oxidation of cyclohexenyl hydroperoxide to a dihydroperoxide takes place simultaneously by a chain mechanism.

Oxidation of cyclohexene in the presence of metal molybdates

1. Under the conditions of low-temperature oxidation of cyclohexene, cobalt(II) molybdate catalyzes the epoxidation of the double bond by the cyclohexene hydroperoxide which is formed. 2. The catalytic function of manganese(II) molybdate is connected with radical breakdown of hydroperoxide on its surface. Parallel with this radical breakdown, molecular decomposition of hydroperoxide takes place on the surface with the formation of cyclohexanone. As well as taking part in chain initiation, manganese molybdate also participates in the radical breakdown stage. 3. The catalytic function of silver molbydate is associated with mutual activated absorption of oxygen and hydroperoxide on its surface. Formation of hydroperoxide takes place in the surface layers without giving rise to radicals in the liquid phase.

Oxidative anodic tosylamidation at a vanadium electrode

Cyclohexene hydroperoxide is converted efficiently to cyclohexenyl tosylamide by electrolysis only at a vanadium anode.

ChemInform Abstract: CATALYTIC TRANSFORMATION OF CYCLOHEXENE HYDROPEROXIDES TO EPOXY ALCOHOLS WITH VANADYL ACETYLACETONATE

Chemischer InformationsdienstVolume 6, Issue 27 Heterocyclic Compounds ChemInform Abstract: CATALYTIC TRANSFORMATION OF CYCLOHEXENE HYDROPEROXIDES TO EPOXY ALCOHOLS WITH VANADYL ACETYLACETONATE TAKASHI ITOH, TAKASHI ITOHSearch for more papers by this authorKIYOTOMI KANEDA, KIYOTOMI KANEDASearch for more papers by this authorSHIICHIRO TERANISHI, SHIICHIRO TERANISHISearch for more papers by this author TAKASHI ITOH, TAKASHI ITOHSearch for more papers by this authorKIYOTOMI KANEDA, KIYOTOMI KANEDASearch for more papers by this authorSHIICHIRO TERANISHI, SHIICHIRO TERANISHISearch for more papers by this author First published: July 8, 1975 https://doi.org/10.1002/chin.197527217Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume6, Issue27July 8, 1975 RelatedInformation

Oxidation by Transition Metal Complexes. VI. Oxidation of Cyclohexenes Catalyzed by Rhodium Complexes

Abstract Rhodium complexes can cause the catalytic oxidation of cyclohexene to give ketone, alcohol, and epoxide. The product distribution is dissimilar to that of the metal-catalyzed decomposition of cyclohexene hydroperoxide(V). Ketone and alcohol are derived from the decomposition of the intermediate hydroperoxide (V) but epoxide is not formed by the oxygen transfer reaction from V. Oxidation of methylcyclohexenes was also studied and discussed in relation to the effect of methyl substituent.

Homogeneous catalysis by transition metal complexes I. The homogeneous cyclohexene oxidation catalysed by low valent tertiary phosphine-transition metal complexes

The oxidation of cyclohexene catalysed by low oxidation state phosphine-transition metal complexes has been studied at 65° and 1 atm of oxygen. The process is a radical reaction but no marked oxygen activation promoted by coordination on the transition metal is usually involved, and the effective action of transition metal complexes is related to their interaction with performed cyclohexene hydroperoxide to form radicals. Only in few cases is oxygen activation probably involved.

Contribution to the study of mechanism of stabilizing action of esters of phosphorous acid

AbstractThe rate of the reaction of a series of phosphites with cyclohexene hydroperoxide and cyclohexene peroxy radicals was studied. The results of the measurements were compared with the stabilization efficiency of the same compounds in isotactic and in atactic polypropylene at 160°C and 120°C respectively and during the course of atmospheric ageing. It was found the reverse relation between the stabilization efficiency and the reaction constants of the reaction of phosphites with hydroperoxides. The main stabilization reaction of the phosphorous stabilizers seems to be the reaction of phosphites or of their decomposition products with radicals. The possibility of splitting off of free phenol from phosphites as a result of the reaction of the esters with hydroperoxide groups was checked.