Catalytic epoxidation of alkenes in the presence of a weakly acidic cation exchanger containing transition metal ions

Котов, С. В.; Boneva, S.

doi:10.1016/s1381-1169(98)00208-8

Cited by 13 publications

(3 citation statements)

References 6 publications

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“…Similarly, Mo, V, and Ti cations on weakly acidic resins (Wofatit CA20) were examined; molybdenum was determined to be the most active metal with TBHP for epoxidation of cyclohexene, styrene, 2,4,4-trimethyl-1-pentenes (and 2,4,4-trimethyl-2-pentenes) and 1-octene. Nine repeated recyclings showed that 10% of the initial molybdenum was lost …”

Section: Oxidation Hydroxylation and Epoxidationmentioning

confidence: 99%

“…Nine repeated recyclings showed that 10% of the initial molybdenum was lost. 215 Terpenes such as limonene, camphene, R-pinene, and β-pinene were epoxidized by TBHP and CHP, in the presence of molybdic ions; both the oxidants showed conversions in the range of 70%-80%, given the neutrality and the nonaqueous conditions of the system: 216 The epoxidation of cyclohexene was examined with several phospho-and phosphono-peroxotungstic anions exchanged on polyacrylate-based quaternary ammonium resins; a commercial Amberlite IRA 918 was examined and compared with other resins obtained by co-polymerization of (meth)acrylate monomers, including glycidyl-, methyl-, or butyl-and ethylene glycol di-(meth)acrylate: Amberlite-supported catalysts afforded mainly allylic oxidation products (40% of 2-cyclohexenol and cyclohexenone); epoxycyclohexane was obtained at 84% yield with the hydrophilic co-polymers. 217 Porphyrins and phthalocyanins were developed to mimic the oxidation behavior of some cytochrome-based enzymes.…”

Section: Oxidation Hydroxylation and Epoxidationmentioning

confidence: 99%

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Organic Synthesis by Catalysis with Ion-Exchange Resins

Gelbard

2005

Ind. Eng. Chem. Res.

180

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This review is intended to give a wide scope on the uses of ion-exchange resins as catalysts or catalyst precursors in organic synthesis, for the preparation of fine or intermediate chemicals. Twelve families of reaction have been covered and presented according to the molecules to be synthesized, regardless of the anionic or cationic nature of the resins; thus, ∼300 references have been selected from January 1980. In acid-catalyzed reactions, the contribution of both Lewis acidity and Bro ¨nsted acidity are mentioned, and, when available, some aspects related to the stability or the recycling of the catalysts are reported. In base-catalyzed reactions, the importance of the thermal stability of anionic resins has been underlined. A table that is included as an appendix provides some data on the resins quoted here.

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Section: Oxidation Hydroxylation and Epoxidationmentioning

confidence: 99%

Section: Oxidation Hydroxylation and Epoxidationmentioning

confidence: 99%

Organic Synthesis by Catalysis with Ion-Exchange Resins

Gelbard

2005

Ind. Eng. Chem. Res.

180

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“…Metals supported on ion exchange resins have been studied in several processes, such as the reduction of nitrates on drinking water, the elimination of oxygen dissolved in water, − alkene epoxidation and hydroformylation of styrene . Particularly, palladium supported on resins has been addressed in several publications and reaction systems − with particular attention on hydrogenations and nitrates reduction …”

Section: Introductionmentioning

confidence: 99%

Catalytic Deoxygenation of Water: Preparation, Deactivation, and Regeneration of Palladium on a Resin Catalyst

Gross

Pisarello

Pierpauli

et al. 2009

Ind. Eng. Chem. Res.

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Oxygen dissolved in water is a cause of corrosion in heating installations. On the other hand, in the production of beverages such as beer, it leads to the oxidation of organic matter, decreasing the quality of the product. Therefore, its content must be substantially reduced. In this work, the catalytic deoxygenation of water using a palladium catalyst is studied. The catalyst consists of palladium ion-exchanged on a weak-basic macroporous resin. This work addresses the catalytic deactivation and regeneration of this type of catalyst, comparing results obtained in the laboratory with those obtained from an industrial reactor used to deoxygenate water for beer production. Two deactivation mechanisms are observed: (i) In the short term, the deposition of organic material (humic acids) coming with the water is responsible for activity lost; (ii) in the long term, the cause of the irreversible deactivation is the palladium leaching that occurs during the cleaning-in-place procedure, which is carried out with sodium hydroxide solution at 60 °C. This deactivation occurs in the presence of dissolved oxygen and is strongly favored by the presence of chlorine in the water. This study indicates the conditions necessary to regenerate the catalyst and to largely improve the stability during operation−regeneration cycles.

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Epoxidation – Homogeneous

Merlau

Borg‐Breen

Nguyen

2002

Encyclopedia of Catalysis

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In this article, catalyst systems for homogeneous epoxidation are reviewed with an emphasis on reaction elements that are of foremost interest to synthetic chemists: catalyst systems, substrate scope, and selectivity. General mechanisms and reaction conditions for each catalyst system are discussed followed by more detailed summaries of the epoxidation of specific classes of olefins: unfunctionalized terminal olefins, cis‐disubstituted, trans‐disubstituted, tri‐ and tetrasubstituted olefins, functionalized olefins including allylic alcohols, and electron‐deficient olefins. Major classes of catalysts addressed are early transition metal‐peroxo forming catalysts (inclusive of the Sharpless titanium tartrate catalyst for the asymmetric epoxidation of allylic alcohols and MTO), metal‐oxo forming catalysts (such as metalloporphyrin and Jacobsen/Katsuki salen catalysts), dioxirane and oxaziridine catalysts, Lewis acid and lanthanide catalysts, phase‐transfer and polyamino acid catalysts, and finally sulfur ylide catalysts for the formation of epoxides from aldehydes. Dedicated to Professor K. Barry Sharpless on the occasion of his 60th birthday.

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Catalytic epoxidation of alkenes in the presence of a weakly acidic cation exchanger containing transition metal ions

Cited by 13 publications

References 6 publications

Organic Synthesis by Catalysis with Ion-Exchange Resins

Organic Synthesis by Catalysis with Ion-Exchange Resins

Catalytic Deoxygenation of Water: Preparation, Deactivation, and Regeneration of Palladium on a Resin Catalyst

Epoxidation – Homogeneous

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