cas 24560-98-3, CIS-9,10-EPOXYSTEARIC ACID

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Lipase catalysed oxidations in a sugar-derived natural deep eutectic solvent
Chemoenzymatic oxidations involving the CAL-B/H2O2 system was developed in a sugar derived Natural Deep Eutectic Solvent (NaDES) composed by a mixture of glucose, fructose and sucrose. Good to excellent conversions of substrates like cyclooctene, limonene, oleic acid and stilbene to their corresponding epoxides, cyclohexanone to its corresponding lactone and 2-phenylacetophenone to its corresponding ester, demonstrate the viability of the sugar NaDES as a reaction medium for epoxidation and Baeyer-Villiger oxidation.
Vagnoni, Martina,Samorì, Chiara,Pirini, Daniele,Vasquez De Paz, Maria Katrina,Gidey, Dawit Gebremichael,Galletti, Paola
(2021/05/06)

Reactive Species and Reaction Pathways for the Oxidative Cleavage of 4-Octene and Oleic Acid with H2O2over Tungsten Oxide Catalysts
Oxidative cleavage of carbon-carbon double bonds (C-C) in alkenes and fatty acids produces aldehydes and acids valued as chemical intermediates. Solid tungsten oxide catalysts are low cost, nontoxic, and selective for the oxidative cleavage of C-C bonds with hydrogen peroxide (H2O2) and are, therefore, a promising option for continuous processes. Despite the relevance of these materials, the elementary steps involved and their sensitivity to the form of W sites present on surfaces have not been described. Here, we combine in situ spectroscopy and rate measurements to identify significant steps in the reaction and the reactive species present on the catalysts and examine differences between the kinetics of this reaction on isolated W atoms grafted to alumina and on those exposed on crystalline WO3 nanoparticles. Raman spectroscopy shows that W-peroxo complexes (W-(η2-O2)) formed from H2O2 react with alkenes in a kinetically relevant step to produce epoxides, which undergo hydrolysis at protic surface sites. Subsequently, the CH3CN solvent deprotonates diols to form alpha-hydroxy ketones that react to form aldehydes and water following nucleophilic attack of H2O2. Turnover rates for oxidative cleavage, determined by in situ site titrations, on WOx-Al2O3 are 75% greater than those on WO3 at standard conditions. These differences reflect the activation enthalpies (ΔH?) for the oxidative cleavage of 4-octene that are much lower than those for the isolated WOx sites (36 ± 3 and 60 ± 6 kJ·mol-1 for WOx-Al2O3 and WO3, respectively) and correlate strongly with the difference between the enthalpies of adsorption for epoxyoctane (ΔHads,epox), which resembles the transition state for epoxidation. The WOx-Al2O3 catalysts mediate oxidative cleavage of oleic acid with H2O2 following a mechanism comparable to that for the oxidative cleavage of 4-octene. The WO3 materials, however, form only the epoxide and do not cleave the C-C bond or produce aldehydes and acids. These differences reflect the distinct site requirements for these reaction pathways and indicate that acid sites required for diol formation are strongly inhibited by oleic acids and epoxides on WO3 whereas the Al2O3 support provides sites competent for this reaction and increase the yield of the oxidative cleavage products.
Yun, Danim,Ayla, E. Zeynep,Bregante, Daniel T.,Flaherty, David W.
p. 3137 - 3152
(2021/04/06)

Quantification and molecular imaging of fatty acid isomers from complex biological samples by mass spectrometry
Elucidating the isomeric structure of free fatty acids (FAs) in biological samples is essential to comprehend their biological functions in various physiological and pathological processes. Herein, we report a novel approach of using peracetic acid (PAA) induced epoxidation coupled with mass spectrometry (MS) for localization of the CC bond in unsaturated FAs, which enables both quantification and spatial visualization of FA isomers from biological samples. Abundant diagnostic fragment ions indicative of the CC positions were produced upon fragmentation of the FA epoxides derived from either in-solution or on-tissue PAA epoxidation of free FAs. The performance of the proposed approach was evaluated by analysis of FAs in human cell lines as well as mapping the FA isomers from cancer tissue samples with MALDI-TOF/TOF-MS. Merits of the newly developed method include high sensitivity, simplicity, high reaction efficiency, and capability of spatial characterization of FA isomers in tissue samples.
Jagodinsky, Justin C.,Li, Lingjun,Li, Zihui,Liu, Yuan,Ma, Min,Morris, Zachary S.,Shi, Xudong,Welham, Nathan V.,Xu, Meng,Zhang, Hua
p. 8115 - 8122
(2021/06/22)

PROCESS FOR THE PREPARATION OF HYDROPEROXY ALCOHOLS USING A HETEROGENOUS CATALYST
The present invention relates to a process for preparing hydroperoxy alcohols using hydrogen peroxide as an oxidant in a solvent selected from water-soluble carboxylic acids, in the presence of a metallic mixed oxide heterogeneous catalyst. It also pertains to the use of this catalyst in the synthesis of hydroperoxy alcohols.
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Page/Page column 14-16-20

(2021/07/02)

An assay for DNA polymerase β lyase inhibitors that engage the catalytic nucleophile for binding
DNA polymerase β (Pol β) repairs cellular DNA damage. When such damage is inflicted upon the DNA in tumor cells treated with DNA targeted antitumor agents, Pol β thus diminishes their efficacy. Accordingly, this enzyme has long been a target for antitumor therapy. Although numerous inhibitors of the lyase activity of the enzyme have been reported, none has yet proven adequate for development as a therapeutic agent. In the present study, we developed a new strategy to identify lyase inhibitors that critically engage the lyase active site primary nucleophile Lys72 as part of the binding interface. This involves a parallel evaluation of the effect of the inhibitors on the wild-type DNA polymerase β (Pol β) and Pol β modified with a lysine analogue at position 72. A model panel of five structurally diverse lyase inhibitors identified in our previous studies (only one of which has been published) with unknown modes of binding were used for testing, and one compound, cis-9,10-epoxyoctadecanoic acid, was found to have the desired characteristics. This finding was further corroborated by in silico docking, demonstrating that the predominant mode of binding of the inhibitor involves an important electrostatic interaction between the oxygen atom of the epoxy group and Nε of the main catalytic nucleophile, Lys72. The strategy, which is designed to identify compounds that engage certain structural elements of the target enzyme, could find broader application for identification of ligands with predetermined sites of binding.
Chen, Shengxi,Cheng, Qi,Daskalova, Sasha M.,Eisenhauer, Brian M.,Fahmi, NourEddine,Feng, Xizhi,Gao, Mingxuan,Hecht, Sidney M.,Ji, Xun,Khdour, Omar M.
supporting information

(2020/07/21)

A fluorescence-based activity assay for immobilized lipases in non-native media
A new method for the analysis of lipase activity in the immobilized state is developed. The fluorescence assay aims to quantify the potential of lipases for the application in organic solvents. As lipases are universally immobilized on polymeric carriers for the use in bioorganic synthesis, the assay includes an immobilization step on the walls of polymeric cuvettes. The activity of the immobilized lipase is probed by 4-methylumbelliferyl ester hydrolysis. The activity retention as a function of solvent concentration is used as a measure for the solvent resistance of the enzyme variant. The method is applied to two different lipases, Candida antarctica lipase B (CalB) and Bacillus subtilis lipase A (BSLA) in the presence of the solvents acetonitrile and ethanol. By comparison of the assay results with a commercial biocatalyst consisting of CalB on polymeric carrier (Novozyme 435) it is demonstrated that the assay allows a good prediction of the activity of the respective lipase as immobilisate on polymeric carriers. The assay surpasses the respective analysis in solution in terms of accuracy and precision.
Ingenbosch, Kim N.,Rousek, Anna,Wunschik, Dennis S.,Hoffmann-Jacobsen, Kerstin
p. 22 - 27
(2019/01/30)

Highly efficient epoxidation of vegetable oils catalyzed by a manganese complex with hydrogen peroxide and acetic acid
Epoxidized vegetable oils (EVOs) are versatile building blocks for lubricants, plasticizers, polyvinyl chloride (PVC) stabilizers, and surface coating formulations. In this paper, a catalytic protocol for the efficient epoxidation of vegetable oils is presented that is based on a combination of a manganese catalyst, H2O2 as an oxidant, and acetic acid as an additive. This protocol relies on the use of a homogeneous catalyst based on the non-noble metal manganese in combination with a racemic mixture of the N,N′-bis(2-picolyl)-2,2′-bispyrrolidine ligand (rac-BPBP). The optimized reaction conditions entail only 0.03 mol% of the manganese catalyst with respect to the number of double bonds (ca. 0.1 wt% with respect to the oil) and ambient temperature. This epoxidation protocol is highly efficient, since it allows most of the investigated vegetable oils, including cheap waste cooking oil, to be fully epoxidized to EVOs in more than 90% yield with excellent epoxide selectivities (>90%) within 2 h of reaction time. In addition, the protocol takes place in a biphasic reaction medium constituted by the vegetable oil itself and an aqueous acetic acid phase, from which the epoxidized product can be easily separated via simple extraction. In terms of efficiency and reaction conditions, the current epoxidation protocol outperforms previously reported catalytic protocols for plant oil epoxidation, representing a promising alternative method for EVO production.
Chen, Jianming,De Liedekerke Beaufort, Marc,Gyurik, Lucas,Dorresteijn, Joren,Otte, Matthias,Klein Gebbink, Robertus J. M.
p. 2436 - 2447
(2019/05/21)

Tailoring chemoenzymatic oxidation: Via in situ peracids
Epoxidation chemistry often suffers from the challenging handling of peracids and thus requires in situ preparation. Here, we describe a two-phase enzymatic system that allows the effective generation of peracids and directly translate their activity to the epoxidation of olefins. We demonstrate the approach by application to lipid and olefin epoxidation as well as sulfide oxidation. These methods offer useful applications to synthetic modifications and scalable green processes.
Re, Rebecca N.,Proessdorf, Johanna C.,La Clair, James J.,Subileau, Maeva,Burkart, Michael D.
supporting information
p. 9418 - 9424
(2019/11/14)

Selective Epoxidation of Fatty Acids and Fatty Acid Methyl Esters by Fungal Peroxygenases
Recently discovered fungal unspecific peroxygenases from Marasmius rotula and Chaetomium globosum catalyze the epoxidation of unsaturated fatty acids (FA) and FA methyl esters (FAME), unlike the well-known peroxygenases from Agrocybe aegerita and Coprinopsis cinerea. Reactions of a series of unsaturated FA and FAME with cis-configuration revealed high (up to 100 %) substrate conversion and selectivity towards epoxidation, although some significant differences were observed between enzymes and substrates with the best results being obtained with the C. globosum enzyme. This and the M. rotula peroxygenase appear as promising biocatalysts for the environmentally-friendly production of reactive FA epoxides given their self-sufficient monooxygenase activity and the high conversion rate and epoxidation selectivity.
Aranda, Carmen,Olmedo, Andrés,Kiebist, Jan,Scheibner, Katrin,del Río, José C.,Martínez, Angel T.,Gutiérrez, Ana
p. 3964 - 3968
(2018/08/11)

Allyl-Palladium-Catalyzed α,β-Dehydrogenation of Carboxylic Acids via Enediolates
A highly practical and step-economic α,β-dehydrogenation of carboxylic acids via enediolates is reported through the use of allyl-palladium catalysis. Dianions underwent smooth dehydrogenation when generated using Zn(TMP)2?2 LiCl as a base in the presence of excess ZnCl2, thus avoiding the typical decarboxylation pathway of these substrates. Direct access to 2-enoic acids allows derivatization by numerous approaches.
Zhao, Yizhou,Chen, Yifeng,Newhouse, Timothy R.
supporting information
p. 13122 - 13125
(2017/09/13)

Identification and Quantitation of C=C Location Isomers of Unsaturated Fatty Acids by Epoxidation Reaction and Tandem Mass Spectrometry
Unsaturated fatty acids (FAs) serve as nutrients, energy sources, and signaling molecules for organisms, which are the major components for a large variety of lipids. However, structural characterization and quantitation of unsaturated FAs by mass spectrometry remain an analytical challenge. Here, we report the coupling of epoxidation reaction of the C=C in unsaturated FAs and tandem mass spectrometry (MS) for rapid and accurate identification and quantitation of C=C isomers of FAs in a shotgun lipidomics approach. Epoxidation of the C=C leads to the production of an epoxide which, upon collision induced dissociation (CID), produces abundant diagnostic ions indicative of the C=C location. The total intensity of the same set of diagnostic ions for one specific FA C=C isomer was also used for its relative and absolute quantitation. The simple experimental setup, rapid reaction kinetics (90% for monounsaturated FAs), and easy-to-interpret tandem MS spectra enable a promising methodology particularly for the analysis of unsaturated FAs in complex biological samples such as human plasma and animal tissues.
Zhao, Yaoyao,Zhao, Hansen,Zhao, Xu,Jia, Jia,Ma, Qiang,Zhang, Sichun,Zhang, Xinrong,Chiba, Hitoshi,Hui, Shu-Ping,Ma, Xiaoxiao
p. 10270 - 10278
(2017/10/13)

Halofunctionalization of alkenes by vanadium chloroperoxidase from: Curvularia inaequalis
The vanadium-dependent chloroperoxidase from Curvularia inaequalis is a stable and efficient biocatalyst for the hydroxyhalogenation of a broad range of alkenes into halohydrins. Up to 1 200 000 TON with 69 s-1 TOF were observed for the biocatalyst. A bienzymatic cascade to yield epoxides as reaction products is presented.
Dong, Jia Jia,Fernández-Fueyo, Elena,Li, Jingbo,Guo, Zheng,Renirie, Rokus,Wever, Ron,Hollmann, Frank
supporting information
p. 6207 - 6210
(2017/07/10)

Strategies for synthesis of epoxy resins from oleic acid derived from food wastes
The use of biomass-sourced chemical feedstocks creates a conflict over land use between food and fuel/chemical production. Such conflict could be reduced by making use of the annual 1.3 Pg food waste resource. Oleic acid is available from seed oils such as pumpkin, grape, avocado and mango. Its esterification with diols 1,3-propanediol, resorcinol and orcinol was used to form diesters and the naturally occurring norspermidine was used to prepare a diamide, all under ambient conditions. These compounds were then epoxidized and polymerized. When esterification was followed by epoxidation and subsequent curing at elevated temperature with p-phenylenediamine or diethylenetriamine, hard insoluble resins were formed. When the sequence was changed such that the epoxidized oleic acid was first reacted with cis-1,2-cyclohexanedicarboxylic anhydride and then esterified with orcinol and resorcinol, insoluble crosslinked polymers were also obtained.
Hayes, Theodore,Hu, Yingxue,Sanchez-Vazquez, Sandra A.,Hailes, Helen C.,Aliev, Abil E.,Evans, Julian R. G.
p. 3159 - 3170
(2016/10/04)

Industrial resin "INDION 130" modified with vanadyl cations as highly efficient heterogeneous catalyst for epoxidation of fatty compounds with TBHP as oxidant
Industrial grade cation-exchange resin "INDION 130" was modified with vanadyl cations by an ion-exchange method and then used for the epoxidation of unsaturated fatty materials including acids, esters and vegetable oils using tert-butyl hydroperoxide (TBHP) in decane as oxidant. The effect of oxidant/double bond ratio, catalyst concentration, recycling of the catalyst and temperature on the conversion to epoxides was studied. After the epoxidation, the catalyst could easily be recovered by filtration and successfully reused for at least seven runs without any loss in catalytic activity.
Khatri, Praveen K.,Aila, Mounika,Porwal, Jyoti,Kaul, Savita,Jain, Suman L.
p. 5960 - 5965
(2015/08/18)

Surfactants derived from epoxidized oils and compositions thereof
Present invention relates to surfactants derived from epoxidized oils and compositions thereof. Particularly this invention describes surfactants derived from epoxidized oils covalently attached to water soluble polymers via thioether bond forming linker and formulations thereof.
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Page/Page column 5

(2015/07/27)

Immobilized oxo-vanadium Schiff base on graphene oxide as an efficient and recyclable catalyst for the epoxidation of fatty acids and esters
Oxo-vanadium Schiff base was covalently immobilized onto chemically functionalized graphene oxide (GO) using 3-aminopropyltriethoxysilane as a coupler. The loading of vanadyl Schiff base onto GO nanosheets was confirmed by FTIR, XRD, TGA, and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The synthesized heterogeneous catalyst was found to be efficient and selective for the epoxidation of fatty acids and esters using t-butyl hydroperoxide (TBHP) as an oxidant. Interestingly, the immobilized catalyst showed a higher catalytic efficiency than the homogeneous vanadyl acetylacetonate. The recycling experiment results indicated that the catalyst was highly stable and maintained very high activity, and selectivity even after being used for six cycles. This journal is the Partner Organisations 2014.
Verma, Sanny,Aila, Mounika,Kaul, Savita,Jain, Suman L.
p. 30598 - 30604
(2014/08/05)

Epoxidation of alkenes bearing a carboxylic acid group by iron complexes of the tetradentate ligand N,N′-dimethyl-N,N′-bis(2-pyridylmethyl)-1, 2-diaminoethane and its derivatives
The addition of carboxylic acids enhances the rate and selectivity of alkene oxidations catalyzed by [(bpmen)Fe(OTf)2] (bpmen = N,N′-dimethyl-N,N′-bis(2-pyridylmethyl)-1,2-diaminoethane). The syntheses and characterizations of four derivatives of this iron complex with varying substitutions on the pyridine ring and with a substituted piperazine backbone are reported. These [(L)Fe(OTf)2] complexes and [(bpmen)Fe(OTf)2] are employed as catalysts for the oxidation of alkenes bearing a carboxylic acid functional group, namely oleic acid, undecylenic acid, 5-hexenoic acid and 4-pentenoic acid, with hydrogen peroxide as the oxidant. Comparisons with the analogous ester substrates demonstrate the beneficial impact of the acid functional group on conversion and selectivity when using [(bpmen)Fe(OTf)2] as a catalyst. For the oleic and undecylenic acids, epoxide product is formed with moderate to high conversions and high selectivities. Under the conditions employed, 4-pentenoic acid is oxidized to a γ-lactone, most likely via the epoxide intermediate, and 5-hexenoic acid to a mixture of epoxide and δ-lactone. Of the iron complexes with bpmen derivatives as ligands, only the N,N′-dimethyl-N, N′-bis(5-chloropyridin-2-ylmethyl)-1,2-diaminoethane variant shows appreciable activity. The effect of solvent choice is also investigated.
Morris, Lilliana S.,Girouard, Michael P.,Everhart, Matthew H.,McClain, William E.,Van Paridon, John A.,Pike, Robert D.,Goh, Christopher
p. 149 - 159
(2014/03/21)

Fe(6-Me-PyTACN)-catalyzed, one-pot oxidative cleavage of methyl oleate and oleic acid into carboxylic acids with H2O2 and NaIO 4
The first Fe-based catalytic system for the oxidative cleavage of unsaturated fatty acids and esters to carboxylic acids is reported. The system comprises [Fe(OTf)2(6-Me-PyTACN)] (2) (6-Me-PyTACN = 1-[(6-methyl-2-pyridyl)methyl]-4,7-dimethyl-1,4,7-triazacyclononane, OTf = trifluoromethane sulfonate anion) as the catalyst (3 mol%) either with a combination of hydrogen peroxide and NaIO4 or exclusively with NaIO4 as the oxidant, and operates at 0 °C or ambient temperature. Under these standard conditions (method A), methyl oleate is converted in a one-pot procedure into 50-55% of both nonanoic and azelaic acid, together with some epoxide and aldehyde intermediates as byproducts. These yields can be further improved by addition of sulfuric acid (method B) to hydrolyze the epoxide byproducts, by including a pH neutralization step and addition of more catalyst (1 mol%). Under the optimized conditions, both methyl oleate and oleic acid are converted into high yields of the corresponding carboxylic acids (80-85%). Overall, this catalytic system provides an alternative to the industrial ozonolysis of oleic acid and to catalytic Ru- and Os-based systems for the oxidative cleavage of unsaturated fatty acids and esters.
Spannring, Peter,Prat, Irene,Costas, Miquel,Lutz, Martin,Bruijnincx, Pieter C. A.,Weckhuysen, Bert. M.,Klein Gebbink, Robertus J. M.
p. 708 - 716
(2014/03/21)

METHOD OF OXIDATIVE MOLECULAR CLEAVAGE OF A FATTY COMPOUND
A method of oxidative molecular cleavage of a fatty compound, includes: —forming a liquid composition, referred to as a fatty composition, consisting of at least one aliphatic carboxylic acid, the fatty composition including the fatty compound; characterised in that it then involves: —adding, to the fatty composition, a solution of at least one quaternary ammonium salt in water capable of forming an emulsion from the fatty compound and water, then; —adding, to the emulsion, a liquid solution of at least one tungstophosphoric acid in a composition including hydrogen peroxide (H2O2), in such a way as to form, in situ in the emulsion, a quantity of a phase-transfer catalyst, formed from tungstophosphoric acid and at least one quaternary ammonium from the quaternary ammonium salt(s), and to allow the oxidative molecular cleavage of the fatty compound.
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Paragraph 0085-0087

(2015/01/06)

Molecular characterization of NbEH1 and NbEH2, two epoxide hydrolases from Nicotiana benthamiana
Plant epoxide hydrolases (EH) form two major clades, named EH1 and EH2. To gain a better understanding of the biochemical roles of the two classes, NbEH1.1 and NbEH2.1 were isolated from Nicotiana benthamiana and StEH from potato and heterologously expressed in Escherichia coli. The purified recombinant proteins were assayed with a variety of substrates. NbEH1.1 only accepted some aromatic epoxides, and displayed the highest enzyme activity towards phenyl glycidyl ether. In contrast, NbEH2.1 displayed a broad substrate range and similar substrate specificity as StEH. The latter enzymes showed activity towards all fatty acid epoxides examined. The activity (Vmax) of NbEH1.1 towards phenyl glycidyl ether was 10 times higher than that of NbEH2.1. On the contrary, NbEH2.1 converted cis-9,10-epoxystearic acid with Vmax of 3.83 μmol min mg-1 but NbEH1.1 could not hydrolyze cis-9,10- epoxystearic acid. Expression analysis revealed that NbEH1.1 is induced by infection with tobacco mosaic virus (TMV) and wounding, whereas NbEH2.1 is present at a relatively constant level, not influenced by treatment with TMV and wounding. NbEH1.1 transcripts were present predominantly in roots, whereas NbEH2.1 mRNAs were detected primarily in leaves and stems. Overall, these two types of tobacco EH enzymes are distinguished not only by their gene expression, but also by different substrate specificities. EH1 seems not to participate in cutin biosynthesis and it may play a role in generating signals for activation of certain defence and stress responses in tobacco. However, members of the EH2 group hydrate fatty acid epoxides and may be involved in cutin monomer production in plants.
Huang, Fong-Chin,Schwab, Wilfried
p. 6 - 15
(2013/07/11)

Fe-catalyzed one-pot oxidative cleavage of unsaturated fatty acids into aldehydes with hydrogen peroxide and sodium periodate
A one-pot method has been developed for the oxidative cleavage of internal alkenes into aldehydes by using 0.5mol % of the nonheme iron complex [Fe(OTf)2(mix-bpbp)] (bpbp=N,N'-bis(2-picolyl)-2,2'-bipyrrolidine) as catalyst and 1.5equivalents of hydrogen peroxide and 1equivalent of sodium periodate as oxidants. A mixture of diastereomers of the chiral bpbp ligand can be used, thereby omitting the need for resolution of its optically active components. The cleavage reaction can be performed in one pot within 20h and under ambient conditions. Addition of water after the epoxidation, acidification and subsequent pH neutralization are crucial to perform the epoxidation, hydrolysis, and subsequent diol cleavage in one pot. High aldehyde yields can be obtained for the cleavage of internal aliphatic double bonds with cis and trans configuration (86-98 %) and unsaturated fatty acids and esters (69-96 %). Good aldehyde yields are obtained in reactions of trisubstituted and terminal alkenes (62-63 %). The products can be easily isolated by a simple extraction step with an organic solvent. The presented protocol involves a lower catalyst loading than conventional methods based on Ru or Os. Also, hydrogen peroxide can be used as the oxidant in this case, which is often disproportionated by second- and third-row metals. By using only mild oxidants, overoxidation of the aldehyde to the carboxylic acid is prevented. Copyright
Spannring, Peter,Yazerski, Vital,Bruijnincx, Pieter C. A.,Weckhuysen, Bert M.,Klein Gebbink, Robertus J. M.
p. 15012 - 15018
(2013/11/06)

Acidic three-liquid-phase microemulsion systems based on balanced catalytic surfactant for epoxidation and sulfide oxidation under mild conditions
Didecyldimethylammonium tungstate has been designed as a balanced catalytic surfactant to form acidic three-liquid-phase microemulsion systems at room temperature in the presence of water, a non-chlorinated solvent and dimethyldioctylammonium salts (hydrogen sulfate and dihydrogen phosphate). The triphasic system is efficient for the oxidation of olefins, sulfides and thiophenes under mild conditions. Moreover, the recovery and reusability of the catalyst, the straightforward separation of products and catalysts in two distinct phases as well as the possible use of environmentally friendly solvents such as tert-butyl acetate, make this system particularly attractive for catalytic oxidation reactions involving hydrogen peroxide as the primary oxidant under acidic or neutral conditions.
Fressancourt-Collinet, Marion,Hong, Bing,Leclercq, Loic,Alsters, Paul L.,Aubry, Jean-Marie,Nardello-Rataj, Veronique
supporting information
p. 409 - 420
(2013/05/22)

Epoxidation of oleic acid catalyzed by PSCI-Amano lipase optimized by experimental design
The present work focuses on the oleic acid epoxide production by using PSCI Amano Lipase as biocatalyst in the reaction. An experimental design (central composite design - CCD) adopting surface response was applied to this purpose. Reactions were performed in a shaker equipment and different variables were investigated, such as temperature (25-55 °C), enzyme load (10-20 wt% of oleic acid mass), hydrogen peroxide load (0.1-0.2%) and reaction time. PSCI-Amano enzyme showed its best behavior as biocatalyst after 3 h of reaction at 55 °C, 10% enzyme load, 0.2% hydrogen peroxide and, applying 150 rpm as stirring. On these conditions, the epoxide yield was around 88%.
Correa, Flavia De Abreu,Sutili, Felipe K.,Miranda, Leandro S.M.,Leite, Selma G.F.,De Souza, Rodrigo O.M.A.,Leal, Ivana C.R.
experimental part
p. 7 - 11
(2012/09/08)

Prilezhaev dihydroxylation of olefins in a continuous flow process
Epoxidation of both terminal and non-terminal olefins with peroxy acids is a well-established and powerful tool in a wide variety of chemical processes. In an additional step, the epoxide can be readily converted into the corresponding trans-diol. Batch-wise scale-up, however, is often troublesome because of the thermal instability and explosive character of the peroxy acids involved. This article describes the design and semi-automated optimization of a continuous flow process and subsequent scale-up to preparative production volumes in an intrinsically safe manner. Olefins go with the flow: Prilezhaev dihydroxylation can be performed on a large scale in continuous flow microreactor systems in the oxidation of terminal and internal olefins. Major drivers for a continuous flow process include better control, improved safety, and a faster overall process, leading to a significantly higher throughput. Copyright
Van Den Broek, Bas A. M. W.,Becker, René,K?ssl, Florian,Delville, Mari?lle M. E.,Nieuwland, Pieter J.,Koch, Kaspar,Rutjes, Floris P. J. T.
experimental part
p. 289 - 292
(2012/06/01)

A novel vegetable oil-lactate hybrid monomer for synthesis of high-T g polyurethanes
A study was conducted to introduce a vegetable oil-lactate hybrid monomer for synthesis of high Tg polyurethanes (PU). The conjugation of epoxidized soybean oil (ESO) was investigated, which was prepared by epoxidation of soybean oil using lipase as catalyst, with lactic acid (LA) through ring-opening reaction. It was demonstrated that 1000 mg of ESO and 600 mg of LA were charged in a reactor that contained a stirrer bar. The reactor was purged with nitrogen for around 15 minutes to remove the air and it was sealed. The reaction was allowed to continue for 6 hours and the final reaction mixture was washed with water to remove unreacted chemicals till the pH value of the washing solution turned to 7.0 and the desired product, lactic acid-epoxidized soybean oil (LA-ESO) was recovered by evaporating the water off under reduced pressure.
Miao, Shida,Zhang, Songping,Zhiguo, Su,Wang, Ping
experimental part
p. 243 - 250
(2010/10/20)

Epoxidation of soybean oil using a homogeneous catalytic system based on a molybdenum (VI) complex
The ability of bis(acetyl-acetonato)dioxo-molybdenum (VI) [MoO 2(acac)2] to catalyse the epoxidation of soybean oil in the presence of tert-butyl hydroperoxide as oxidizing agent has been investigated. The influence of reaction time and temperature in the course of the epoxidation reaction was evaluated by quantitative 1H NMR. When epoxidation was carried out in refluxing toluene at 110 °C for 2 h, a 70.1% conversion of substrate was obtained, producing 54.1% epoxidation with a selectivity of 77.2%. The 1H NMR spectroscopic method selected for the purpose of this work allowed a simple and rapid evaluation of the mono- and diepoxides obtained following the epoxidation of soybean oil.
Farias, Maritana,Martinelli, Márcia,Bottega, Diana Pagliocchi
scheme or table
p. 213 - 219
(2010/11/16)

Design of and mechanistic studies on a biomimetic iron-imidazole catalyst system for epoxidation of olefins with hydrogen peroxide
Novel iron catalysts, both defined and in situ generated, for the epoxidation of aromatic and aliphatic olefins with hydrogen peroxide as terminal oxidant are described. Our catalyst approach is based on bio-inspired 1-aryl-substituted imidazoles in combination with cheap and abundant iron trichloride hexahydrate. We show that the free 2-position of the imidazole ligand motif plays a key role for catalytic activity, as substitution leads to a dramatic depletion of yield and conversion. X-ray studies, UV/Vis titrations, and NMR studies were carried out to clarify the mechanism.
Schroeder, Kristin,Enthaler, Stephan,Bitterlich, Bianca,Schulz, Thomas,Spannenberg, Anke,Tse, Man Kin,Junge, Kathrin,Beller, Matthias
experimental part
p. 5471 - 5481
(2009/12/27)

An improved iron-catalyzed epoxidation of aromatic and aliphatic olefins with hydrogen peroxide as oxidant
A convenient and practical method for the iron-catalyzed epoxidation of aromatic and aliphatic olefins is described. The iron catalyst system is generated in situ from iron trichloride hexahydrate, pyridine-2,6-dicarboxylic acid (H2pydic), and benzylamines. By variation of the benzylamine ligand, a variety of aliphatic and aromatic olefins were oxidized in high yield (up to 96%) and good-to-excellent selectivity in the presence of hydrogen peroxide as the terminal oxidant. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
Bitterlich, Bianca,Schroeder, Kristin,Tse, Man Kin,Beller, Matthias
scheme or table
p. 4867 - 4870
(2009/05/26)

Epoxidation of carbon-carbon double bond with membrane bound peroxygenase
A method has been discovered for the epoxidation of a compound having at least one carbon-carbon double bond, the method involves reacting a compound having at least one carbon-carbon double bond, a solvent, an oxidant, and membrane bound peroxygenase. Also discovered is a method for preparing the membrane bound peroxygenase involving grinding seeds containing peroxygenase to produce ground seeds, homogenizing the ground seeds in a buffer to form a slurry, centrifuging the slurry to produce a first supernatant, centrifuging the first supernatant to produce a second supernatant, and filtering said second supernatant through a protein-binding membrane filter to produce membrane bound peroxygenase; optionally the second supernatant is filtered through a hydrophilic membrane filter prior to filtering the second supernatant through a protein-binding membrane filter.
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Page/Page column 6-8

(2008/06/13)

Analysis of fatty acid epoxidation by high performance liquid chromatography coupled with evaporative light scattering detection and mass spectrometry
Conventionally, epoxidation of unsaturated fatty acids has been studied either with titrimetric methods or in a lengthy procedure involving derivatization followed by gas chromatography (GC). We have developed a more rapid and descriptive analysis procedure for the substances using high performance liquid chromatography (HPLC) with evaporative light scattering detection (ELSD). Chemo-enzymatic epoxidation of unsaturated fatty acids (oleic, linoleic and linolenic acid, respectively) has been performed using hydrogen peroxide and immobilized lipase from Candida antarctica (Novozym 435). The fatty acids and their epoxidation products were separated by HPLC on a C-18 reversed-phase column using methanol-water containing 0.05% acetic acid as mobile phase. The method facilitated the simultaneous determination of fatty acids and epoxides differing from each other in the number of epoxide rings, the degree of unsaturation and the position of the epoxide rings and double bonds. An important aspect of the method development was the use of electrospray ionization and tandem mass spectrometry to confirm the structure of the epoxide products. It is suggested that the HPLC method, providing more information about the kind and concentration of fatty acids and their epoxides, represents a powerful complement to the existing methods for monitoring epoxidation processes on fatty acids.
Orellana-Coca, Cecilia,Adlercreutz, Dietlind,Andersson, Maria M.,Mattiasson, Bo,Hatti-Kaul, Rajni
p. 189 - 199
(2007/10/03)

Transition Metal Catalyzed Oxidations in Perfluorinated Solvents
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Klement, Ingo,Luetjens, Henning,Knochel, Paul
p. 1454 - 1456
(2007/10/03)

Enantioconvergent transformation of racemic cis-dialkyl substituted epoxides to (R,R) threo diols by microsomal epoxide hydrolase catalysed hydrolysis
Both enantiomers of (±)-9,10-epoxystearic acid (1b), cis-(±)-5,6-epoxyhexadecane (1c) and cis-(±)-11,12-epoxyhexadecan-1-ol (1d) as well as the meso cis-9,10-epoxyoctadecane (1a) undergo microsomal epoxide hydrolase catalyzed hydration at the (S) carbon to give the corresponding (R,R) threo diols in a >90 e.e. Copyright (C) 1996 Elsevier Science Ltd.
Bellucci, Giuseppe,Chiappe, Cinzia,Cordoni, Antonio,Ingrosso, Giovanni
p. 9089 - 9092
(2007/10/03)

Direct epoxidation of unprotected olefinic carboxylic acids using HOF-CH3CN
The reaction of HOF·CH3CN complex, made directly by passing fluorine through aqueous acetonitrile, with double bond containing unprotected carboxylic acids and alcohols results in fast and almost quantitative epoxidation.
Rozen, Shlomo,Bareket, Yifat,Dayan, Sharon
p. 531 - 534
(2007/10/02)

Application of chemical P-450 model systems to studies on drug metabolism. Part X. Novel hydroxylactonization of γ,δ- and β,γ-unsaturated carboxylic acids with an iron porphyrin-iodosylbenzene system
The oxidative hydroxylactonization of γ,δ- and β,γ-unsaturated carboxylic acids by a chemical cytochrome P-450 model and rat liver microsomal systems has been investigated. In the chemical system using meso-tetrakis(2,6-dichlorophenyl)porphyrin iron chloride [Fe(TDClPP)Cl] with iodosylbenzene (PhIO), γ,δ-unsaturated carboxylic acids have been converted into δ-hydroxy-γ-lactones in high yield and with high stereoselectivity. As an example of a β,γ-unsaturated carboxylic acid, indomethacin has been converted into the corresponding β-hydroxy γ-lactone. Several experiments directed toward mechanistic elucidation of the lactonization exclude a mechanism occurring via an epoxide intermediate. The products have been used as standards to identify the metabolites in the microsomal oxidation. In the case of indomethacin, the γ-lactone form is detected as a metabolite in the rat liver microsomal system, in a yield of 1.33%; the yield is significantly decreased in the presence of 2-diethylaminoethyl-2,2-diphenylvalerate hydrochloride (SKF-525A) and under a mixed CO-O2 (4:1) atmosphere. Thus, these metabolites are considered to be formed by a cytochrome P-450-dependent reaction.
Komuro, Masakatsu,Higuchi, Tsunehiko,Hirobe, Masaaki
p. 2309 - 2313
(2007/10/03)

The action of hypochlorous acid on phosphatidylcholine liposomes in dependence on the content of double bonds. Stoichimetry and NMR analysis
Kinetics of the consumption of hypochlorous acid in its reaction with double bonds of unsaturated phospholipids and fatty acids were measured using luminol chemiluminescence.Stoichiometry ratios between the consumption of HOCl/OCl- and the loss of double bonds vary from 2:1 to 1:1.Highest values were found in DMPC liposomes containing 5 molpercent oleic acid or OPPC.With increasing content of double bonds or higher numbers of double bonds in a fatty acid acyl chain ddue to incorporated unsaturated fatty acids or phospholipids in DMPC liposomes the stoichiometry ratio falls continuously to 1:1.A ratio of about 1:1 was observed in multilamellar and unilamellar liposomes composed of egg yolk phosphatidylcholine.Products of the reaction of oleic acid with hypochlorous acid were analysed by 1H-NMR spectroscopy.Chlorohydrins were formed in both DMPC liposomes containing 5 or 40 molpercent oleic acid.Keywords: Hypochlorous acid; Chlorohydrins; Double bond; Phospholipids; Fatty acids
Arnhold, J.,Panasenko, O. M.,Schiller, J.,Vladimirov, Yu. A.,Arnold, K.
p. 55 - 64
(2007/10/03)

An Efficient Preparation of 18O-Labeled Epoxides
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Borhan, Babak,Nazarian, Saman,Stocking, Emily M.,Hammock, Bruce D.,Kurth, Mark J.
p. 4316 - 4318
(2007/10/02)

SODIUM PERBORATE OXIDATIONS OF CYCLIC AND ACYCLIC ALKENES TO OXIRANES OR VICINAL ACETOXY ALCOHOLS
Under different reaction conditions, sodium perborate/acetic anhydride oxidizes alkenes into oxiranes or vicinal acetoxy alcohols in good yields.
Xie, Gaoyang,Xu, Linxiao,Hu, Jun,Ma, Shiming,Hou, Wei,Tao, Fenggang
p. 2967 - 2968
(2007/10/02)