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Статті в журналах з теми "Olefin oxidation"

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Автор: Grafiati

Опубліковано: 6 вересня 2023

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1

Perkins, Robert J., Hai-Chao Xu, John M. Campbell, and Kevin D. Moeller. "Anodic coupling of carboxylic acids to electron-rich double bonds: A surprising non-Kolbe pathway to lactones." Beilstein Journal of Organic Chemistry 9 (August 9, 2013): 1630–36. http://dx.doi.org/10.3762/bjoc.9.186.

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Carboxylic acids have been electro-oxidatively coupled to electron-rich olefins to form lactones. Kolbe decarboxylation does not appear to be a significant competing pathway. Experimental results indicate that oxidation occurs at the olefin and that the reaction proceeds through a radical cation intermediate.

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2

Rayati, Saeed, Saeed Zakavi, Parisa Jafarzadeh, Omid Sadeghi, and Mostafa M. Amini. "Manganese meso-tetra-4-carboxyphenylporphyrin immobilized on MCM-41 as catalyst for oxidation of olefins with different oxygen donors in stoichiometric conditions." Journal of Porphyrins and Phthalocyanines 16, no. 03 (March 2012): 260–66. http://dx.doi.org/10.1142/s1088424612500307.

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Oxidation of olefins with tert-butyl hydroperoxide (TBHP), tetra-n-butylammonium periodate (TBAP) and potassium peroxomonosulfate (Oxone) in the presence of MCM-41 immobilized meso-tetra-4-carboxyphenylporphyrinatomanganese(III) acetate has been studied. The results of this study show better catalytic performance of the heterogonous catalyst using TBHP as oxidant in comparison with Oxone and TBAP in oxidation of the used olefins with the exception of cyclooctene. However, different order of reactivity of various olefins has been observed in the presence of Oxone and TBHP. In spite of the absence of good electron-withdrawing groups at the periphery of porphyrin ligand, the catalyst was recovered and reused (at least four times) without detectable catalyst leaching or a significant loss of the catalytic efficiency. All results have been obtained in the absence of using excess molar ratios of olefin to the oxidant, commonly employed as a strategy to overcome the instability of metalloporphyrins in oxidative conditions.

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3

Lin, Bo-Lin, Jay A. Labinger, and John E. Bercaw. "Mechanistic investigations of bipyrimidine-promoted palladium-catalyzed allylic acetoxylation of olefins." Canadian Journal of Chemistry 87, no. 1 (January 1, 2009): 264–71. http://dx.doi.org/10.1139/v08-133.

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Several pyridine-like ligands were found to improve Pd(OAc)2-catalyzed allylic oxidation of allylbenzene to cinnamyl acetate by p-benzoquinone in acetic acid. The best ligand examined, bipyrimidine, was used to identify the catalyst precursor for this system, (bipyrimidine)Pd(OAc)2, which was fully characterized. Mechanistic studies suggest the reaction takes place through disproportionation of (bipyrimidine)Pd(OAc)2 to form a bipyrimidine-bridged dimer, which reacts with olefin to form a PdII-olefin adduct, followed by allylic C–H activation to produce (η3-allyl)PdII species. The (η3-allyl)PdII intermediate undergoes a reversible acetate attack to generate a Pd0-(allyl acetate) adduct, which subsequently reacts with p-benzoquinone to release allyl acetate and regenerate (bipyrimidine)Pd(OAc)2. No KIE is observed for the competition experiment between allylbenzene-d0 and allylbenzene-d5 (CD2=CDCD2C6H5), suggesting that allylic C–H activation is not rate-determining. Catalytic allylic acetoxylations of other terminal olefins as well as cyclohexene were also effected by (bipyrimidine)Pd(OAc)2.Key words: olefin, palladium catalysis, allylic C–H oxidation, p-benzoquinone, bipyrimidine.

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4

Křeček, Václav, Jiří Protiva, Miloš Buděšínský, Eva Klinotová, and Alois Vystrčil. "Preparation of C(18)-empiric 20,29,30-trinorlupane derivatives. 1H, 13C NMR and mass spectra." Collection of Czechoslovak Chemical Communications 51, no. 3 (1986): 621–35. http://dx.doi.org/10.1135/cccc19860621.

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Reaction of amide I with nitrous acid gave the olefins II, III and IV. On allylic oxidation of olefin IV α,β-unsaturated ketone V is formed from which olefins VIII and IX were prepared by a sequence of further reactions. Addition of hydrogen to the double bond of olefin IV and α,β-unsaturated ketone V takes place on catalytic hydrogenation from the β-side and leads to derivatives with cis-annellated rings D/E. This made the preparation of hydrocarbons VI and VII epimeric on C(18) possible, which represent reference compounds for the study of the effect of substituents on the chemical shifts of the methyl groups and the saturated carbon atoms of 18αH and 18βH-lupane derivatives. The configuration of the hydroxyl group in epimers XI and XII were derived from 1H NMR spectra. Deuteration of olefins III, IV and IX gave deuteriohydrocarbons XVI to XVIII. The 1H, 13C NMR and mass spectra of the substances prepared are discussed.

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5

STINSON, STEPHEN. "IRON-CATALYZED OLEFIN OXIDATION." Chemical & Engineering News 79, no. 30 (July 23, 2001): 9. http://dx.doi.org/10.1021/cen-v079n030.p009.

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6

Lorber, Christian. "[ONNO]-type amine bis(phenolate)-based vanadium catalysts for ethylene homo- and copolymerization." Pure and Applied Chemistry 81, no. 7 (June 30, 2009): 1205–15. http://dx.doi.org/10.1351/pac-con-08-08-05.

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Анотація:

The synthesis and solution and solid-state structural characterization of a family of amine bis(phenolate) [ONNO]-vanadium complexes is reviewed. These compounds have oxidation states ranging from vanadium(II) to vanadium(V), and were evaluated as olefin polymerization catalysts. In association with EtAlCl2 cocatalyst, we studied the homopolymerization of ethylene, propene, and 1-hexene, as well as the copolymerization of ethylene with α-olefins (1-hexene, 1-octene) and cycloolefins (norbornene, cyclopentene). Some of these catalysts were shown to produce copolymers with a good activity and comonomer content.

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7

Herrmann, Wolfgang A., Richard W. Fischer, and Dieter W. Marz. "Methyltrioxorhenium as Catalyst for Olefin Oxidation." Angewandte Chemie International Edition in English 30, no. 12 (December 1991): 1638–41. http://dx.doi.org/10.1002/anie.199116381.

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8

Fukusumi, Takanori, Natsuki Takei, Yubi Tateno, Takuya Aoki, Ai Ando, Kouhei Kozakai, Hiroko Shima, et al. "Ene-thiol reaction of C3-vinylated chlorophyll derivatives in the presence of oxygen: synthesis of C3-formyl-chlorins under mild conditions." Journal of Porphyrins and Phthalocyanines 17, no. 12 (December 2013): 1188–95. http://dx.doi.org/10.1142/s1088424613500983.

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Reactions of thiol with the C 3-vinyl group of various chlorophyll (Chl) derivatives were examined. The reactions resemble thiol-olefin co-oxidation, except that the vinyl C = C double bond was cleaved to afford a formyl group without any transition metal catalyst, and that the simple anti-Markovnikov adduct of thiol to olefin was obtained as a minor product. Peripheral substituents of Chl derivatives little affected the reaction, while the central metal atom of the chlorin macrocycle influenced the composition of the products. Oxygen and acid dissolved in the reaction mixture can facilitate the oxidation. Sufficiently mild conditions in this regioselective oxidation at the C 31-position are significant in bioorganic chemistry.

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9

Ma, Baochun, Wei Zhao, Fuming Zhang, Yingshuai Zhang, Songyun Wu, and Yong Ding. "A new halide-free efficient reaction-controlled phase-transfer catalyst based on silicotungstate of [(C18H37)2(CH3)2N]3[SiO4H(WO5)3] for olefin epoxidation, oxidation of sulfides and alcohols with hydrogen peroxide." RSC Adv. 4, no. 61 (2014): 32054–62. http://dx.doi.org/10.1039/c4ra04036h.

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10

Patrzałek, Michał, Aleksandra Zasada, Anna Kajetanowicz та Karol Grela. "Tandem Olefin Metathesis/α-Ketohydroxylation Revisited". Catalysts 11, № 6 (9 червня 2021): 719. http://dx.doi.org/10.3390/catal11060719.

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EWG-activated and polar quaternary ammonium salt-tagged ruthenium metathesis catalysts have been applied in a two-step one-pot metathesis-oxidation process leading to functionalized α-hydroxyketones (acyloins). In this assisted tandem process, the metathesis catalyst is used first to promote ring-closing metathesis (RCM) and cross-metathesis (CM) steps, then upon the action of Oxone™ converts into an oxidation catalyst able to transform the newly formed olefinic product into acyloin under mild conditions.

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11

Herrmann, Wolfgang A., Richard W. Fischer, and Dieter W. Marz. "Methyltrioxorhenium als Katalysator für die Olefin-Oxidation." Angewandte Chemie 103, no. 12 (December 1991): 1706–9. http://dx.doi.org/10.1002/ange.19911031234.

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12

Pilic, Branka, Dragoslav Stoiljkovic, Ivana Bakocevic, Slobodan Jovanovic, Davor Panic, and Ljiljana Korugic-Karasz. "The charge percolation mechanism and simulation of Ziegler-Natta polymerizations. Part III. Oxidation states of transition metals." Journal of the Serbian Chemical Society 71, no. 4 (2006): 357–72. http://dx.doi.org/10.2298/jsc0604357p.

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The oxidation state of the transition metal (Mt) active centre is the most disputable question in the polymerization of olefins by Ziegler-Natta (ZN) and metallocene complexes. In this paper the importance and the changes of the Mt active centers are presented and discussed on the basis of a charge percolation mechanism (CPM) of olefin polymerization. Mt atoms can exist in different oxidation states and can be easily transformed from one to another state during activation. In all cases, the Mt atoms are present in several oxidation states, i.e., Mt+(n-1), Mt+(n) to Mt+(n+1), producing an irregular charge distribution over the support surface. There is a tendency to equalize the oxidation states by a charge transfer from Mt+(n-1) (donor) to Mt+(n+1) (acceptor). This cannot occur since the different oxidation states are highly separated on the support. However, monomer molecules are adsorbed on the support producing clusters with stacked ?-bonds, making a ?-bond bridge between a donor and an acceptor. Once a bridge is formed (percolation moment), charge transfer occurs. The donor and acceptor equalize their oxidation states simultaneously with the polymerization of the monomer. The polymer chain is desorbed from the support, freeing the surface for subsequent monomer adsorption. The whole process is repeated with the oxidation-reduction of other donor-acceptor ensembles.

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13

Chen, Ruichao, Yuhong Ma, Changwen Zhao, Zhifeng Lin, Xing Zhu, Lihua Zhang, and Wantai Yang. "Construction of DNA microarrays on cyclic olefin copolymer surfaces using confined photocatalytic oxidation." RSC Adv. 4, no. 87 (2014): 46653–61. http://dx.doi.org/10.1039/c4ra07442d.

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14

Lu, Yue, Han Zhang, Shaojun Liu, Chenglong Li, Lixiang Li, Baigang An, and Chengguo Sun. "Hemin-based conjugated effect synthesis of Fe–N/CNT catalysts for enhanced oxygen reduction." New Journal of Chemistry 45, no. 15 (2021): 6940–49. http://dx.doi.org/10.1039/d1nj00020a.

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15

Bunchuay, T., R. Ketkaew, P. Chotmongkolsap, T. Chutimasakul, J. Kanarat, Y. Tantirungrotechai, and J. Tantirungrotechai. "Microwave-assisted one-pot functionalization of metal–organic framework MIL-53(Al)-NH2 with copper(ii) complexes and its application in olefin oxidation." Catalysis Science & Technology 7, no. 24 (2017): 6069–79. http://dx.doi.org/10.1039/c7cy01941f.

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16

Piola, Lorenzo, Fady Nahra, and Steven P. Nolan. "Olefin metathesis in air." Beilstein Journal of Organic Chemistry 11 (October 30, 2015): 2038–56. http://dx.doi.org/10.3762/bjoc.11.221.

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Анотація:

Since the discovery and now widespread use of olefin metathesis, the evolution of metathesis catalysts towards air stability has become an area of significant interest. In this fascinating area of study, beginning with early systems making use of high oxidation state early transition metal centers that required strict exclusion of water and air, advances have been made to render catalysts more stable and yet more functional group tolerant. This review summarizes the major developments concerning catalytic systems directed towards water and air tolerance.

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17

Carroll, AR, RW Read, and WC Taylor. "Intramolecular Oxidative Coupling of Aromatic Compounds. VII. A Convenient Synthesis of (±)-Deoxyschizandrin." Australian Journal of Chemistry 47, no. 8 (1994): 1579. http://dx.doi.org/10.1071/ch9941579.

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A convenient synthesis of (�)-deoxyschizandrin was achieved through the key step of reductive coupling of the bisacetonylbiphenyl (3). The latter compound was synthesized by oxidative cleavage of the bis olefin (5) formed by Claisen rearrangement of the bismethallyl ether of 2,2′,4,4′-tetramethoxybiphenyl-3,3′-diol. The synthesis of 2,2′,4,4′-tetramethoxy-6,6′-di(prop 1-enyl)biphenyl-3,3′-diol (2) is also described. The diphenolic oxidation of (2) did not lead to products with β,β′ carbons linked.

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18

Singh, Adesh Kumar, Varsha Tiwari, Kunj Bihari Mishra, Surabhi Gupta, and Jeyakumar Kandasamy. "Urea–hydrogen peroxide prompted the selective and controlled oxidation of thioglycosides into sulfoxides and sulfones." Beilstein Journal of Organic Chemistry 13 (June 13, 2017): 1139–44. http://dx.doi.org/10.3762/bjoc.13.113.

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A practical method for the selective and controlled oxidation of thioglycosides to corresponding glycosyl sulfoxides and sulfones is reported using urea–hydrogen peroxide (UHP). A wide range of glycosyl sulfoxides are selectively achieved using 1.5 equiv of UHP at 60 °C while corresponding sulfones are achieved using 2.5 equiv of UHP at 80 °C in acetic acid. Remarkably, oxidation susceptible olefin functional groups were found to be stable during the oxidation of sulfide.

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19

Yi, Jigyoung, Hye Mi Ahn, Jong Ho Yoon, Cheal Kim, and Suk Joong Lee. "Preparation of a bispyridine based porous organic polymer as a new platform for Cu(ii) catalyst and its use in heterogeneous olefin epoxidation." New Journal of Chemistry 42, no. 17 (2018): 14067–70. http://dx.doi.org/10.1039/c8nj02214c.

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A new type of bispyridine (bpy) incorporated POP was prepared via a cobalt-catalyzed acetylene trimerization. Subsequent metalation of CuCl₂ gave POP-Cu(ii) which displayed outstanding olefin oxidation activity.

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20

Nunes, Carla D., Pedro D. Vaz, Vítor Félix, Luis F. Veiros, Tânia Moniz, Maria Rangel, Sara Realista, Ana C. Mourato, and Maria José Calhorda. "Vanadyl cationic complexes as catalysts in olefin oxidation." Dalton Transactions 44, no. 11 (2015): 5125–38. http://dx.doi.org/10.1039/c4dt03174a.

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21

Gimferrer, Martí, Pedro Salvador, and Albert Poater. "Computational Monitoring of Oxidation States in Olefin Metathesis." Organometallics 38, no. 24 (December 4, 2019): 4585–92. http://dx.doi.org/10.1021/acs.organomet.9b00591.

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22

Nunes, Carla D., and Maria José Calhorda. "Molybdenum(II) catalyst precursors in olefin oxidation reactions." Inorganica Chimica Acta 431 (May 2015): 122–31. http://dx.doi.org/10.1016/j.ica.2015.03.018.

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23

OLDENBURG, P., and L. QUEJR. "Bio-inspired nonheme iron catalysts for olefin oxidation." Catalysis Today 117, no. 1-3 (September 30, 2006): 15–21. http://dx.doi.org/10.1016/j.cattod.2006.05.022.

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24

Grate, John H., David R. Hamm, and Suresh Mahajan. "Palladium and phosphomolybdovanadate catalyzed olefin oxidation to carbonyls." Molecular Engineering 3, no. 1-3 (1993): 205–29. http://dx.doi.org/10.1007/bf00999634.

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25

Ogoshi, Hisanobu, Yasuhiko Suzuki, and Yasuhisa Kuroda. "Olefin Oxidation Catalyzed by Electron Deficient Metallo-Porphyrin." Chemistry Letters 20, no. 9 (September 1991): 1547–50. http://dx.doi.org/10.1246/cl.1991.1547.

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26

Wang, Jian-Cheng, Yu-Hong Hu, Gong-Jun Chen, and Yu-Bin Dong. "Cu(ii)/Cu(0)@UiO-66-NH2: base metal@MOFs as heterogeneous catalysts for olefin oxidation and reduction." Chemical Communications 52, no. 89 (2016): 13116–19. http://dx.doi.org/10.1039/c6cc06076e.

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Анотація:

Two copper-loaded MOF materials, Cu(ii)@Ui-O-66-NH₂ (1) and Cu(0)@UiO-66-NH₂ (2), which can be highly active heterogeneous catalysts for olefin oxidation and hydrogenation, are reported.

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27

Song, Xiaojing, Yan Yan, Yanning Wang, Dianwen Hu, Lina Xiao, Jiehui Yu, Wenxiang Zhang, and Mingjun Jia. "Hybrid compounds assembled from copper-triazole complexes and phosphomolybdic acid as advanced catalysts for the oxidation of olefins with oxygen." Dalton Transactions 46, no. 47 (2017): 16655–62. http://dx.doi.org/10.1039/c7dt03198j.

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Hybrid compounds of [CuI4(3atrz)₄][PMoVI11Mo^VO₄₀] (1) and [CuI6(3atrz)₆][PMo₁₂O₄₀]₂ (2) are active catalysts for olefin oxidation.

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28

Iyer, Shyam R., Maedeh Moshref Javadi, Yan Feng, Min Young Hyun, Williamson N. Oloo, Cheal Kim, and Lawrence Que. "A chameleon catalyst for nonheme iron-promoted olefin oxidation." Chem. Commun. 50, no. 89 (September 17, 2014): 13777–80. http://dx.doi.org/10.1039/c4cc06164k.

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29

Saraiva, Marta S., Cristina I. Fernandes, Teresa G. Nunes, Maria José Calhorda, and Carla D. Nunes. "Pore size matters! Helical heterogeneous catalysts in olefin oxidation." Applied Catalysis A: General 504 (September 2015): 328–37. http://dx.doi.org/10.1016/j.apcata.2015.01.040.

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30

Mansour, E. M. K., P. Maillard, P. Krausz, S. Gaspard, and C. Giannotti. "Photochemically induced olefin oxidation by titanyl and vanadyl porphyrins." Journal of Molecular Catalysis 41, no. 3 (August 1987): 361–66. http://dx.doi.org/10.1016/0304-5102(87)80113-x.

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31

Zhang, Baoan, Nengsheng Liu, Qingsong Lin, and Dai Jin. "The effects of Mo oxidation states on olefin metathesis." Journal of Molecular Catalysis 65, no. 1-2 (March 1991): 15–28. http://dx.doi.org/10.1016/0304-5102(91)85078-g.

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32

Dauth, Alexander, and Jennifer A. Love. "Preparation of 2-Azarhodacyclobutanes by Rhodium(I)-Olefin Oxidation." Angewandte Chemie International Edition 51, no. 15 (February 28, 2012): 3634–37. http://dx.doi.org/10.1002/anie.201107669.

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33

Wu, Nan, Zhi-Min Zong, Yi-Wei Fei, Jun Ma та Feng Guo. "Thermal oxidation stability of poly-α -olefin lubricating oil". Asia-Pacific Journal of Chemical Engineering 12, № 5 (вересень 2017): 813–17. http://dx.doi.org/10.1002/apj.2121.

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34

Muñiz, Kilian. "Electronic Effects in Olefin Oxidation by Imidoosmium(VIII) Compounds." European Journal of Organic Chemistry 2004, no. 10 (May 2004): 2243–52. http://dx.doi.org/10.1002/ejoc.200300774.

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35

Dauth, Alexander, and Jennifer A. Love. "Preparation of 2-Azarhodacyclobutanes by Rhodium(I)-Olefin Oxidation." Angewandte Chemie 124, no. 15 (February 28, 2012): 3694–97. http://dx.doi.org/10.1002/ange.201107669.

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36

Pilić, B., D. Stoiljković, I. Bakočević, S. Jovanović, D. Panić, and Lj Korugić-Karasz. "Polymer Structure Prediction by Computer Simulation of Ziegler-Natta Polymerization Based on Charge Percolation Mechanism." Materials Science Forum 518 (July 2006): 381–86. http://dx.doi.org/10.4028/www.scientific.net/msf.518.381.

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Анотація:

Recently, a new charge percolation mechanism (CPM) of the Ziegler-Natta (ZN) polymerization of olefins by supported transition metal (Mt) complexes has been presented: a macromolecular chain is formed by polymerization of the monomer cluster (nM) adsorbed on the support (S) between two immobilized Mt ions, some in the higher (Mtn+1, i.e. acceptors) and the other in the lower (Mtn-1, i.e. donors) oxidation state: (Mtn-1...nM...Mtn+1)/S → (Mtn Mtn)/S + polymer. A special computer program «Lattice» has been developed to simulate olefin polymerization based on CPM using a Monte Carlo procedure. The effects of reaction conditions (Mt concentration, Mt/S ratio, sequence of chemical components addition and time) of ethylene and propylene polymerization by various Mt precursors (TiCl4/MgCl2, CrOx) and supports (MgCl2, SiO2) on molecular mass and molecular mass distribution can be predicted by simulation and confirmed by published experimental results.

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37

Ma, Yuefeng, Jian Xu, Xiangqiong Zeng, Haizhen Jiang, and Jiusheng Li. "Preparation and performance evaluation of mPAO8 using olefin from coal as raw material." Industrial Lubrication and Tribology 69, no. 5 (September 4, 2017): 678–82. http://dx.doi.org/10.1108/ilt-03-2016-0049.

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Purpose The purpose of this paper is to prepare metallocene polyalphaolefin 8 (mPAO8) by the oligomerization of olefin from coal with metallocene catalyst system and compare it with commercially available polyalphaolefin 8 (PAO8) from Chevron. Design/methodology/approach Molecular structures, component and mass were determined by nuclear magnetic resonance spectroscopy, gas chromatography and gel permeation chromatography, respectively. The physico-chemical properties, including Noack volatility, viscosity index and elemental analyses, were studied. The oxidative stability was evaluated by pressurized differential scanning calorimetry, whereas the thermal stability was studied by thermo-gravimetric analysis. Findings The produced mPAO8 consisted of a large part of tetramer, pentamer and a small part of trimer and hexamer. Additive T501 significantly improved the oxidation stability of PAO8 from Chevron and the synthesized mPAO8. Both samples had similar properties, such as oxidative stability, additive response, pour point and Noack volatility loss. But mPAO8 possessed a higher thermal stability, better viscosity index and flash point than PAO8. Therefore, the mPAO8 prepared by the oligomerization of olefin from coal could be used as base oil for lubricant development. Originality/value The mPAO8 base oil was successfully prepared by successive carbon numbers and shows similar properties with commercially available PAO8 products from Chevron. The findings can cover the shortage of the synthesis lubricants market in China.

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38

Chen, Jian, Mengjing Zhu, Fuwei Xiang, Junfeng Li, Hongjun Yang, and Zhipeng Mao. "Research Progress on Microreactor Technology in Oxidation Reactions." Current Organic Chemistry 25, no. 10 (June 1, 2021): 1235–45. http://dx.doi.org/10.2174/1385272825666210319092545.

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In recent years, the development of the chemical industry has been moving in a green, safe and efficient direction. Oxidation reactions are one of the most important types of reactions and have key applications in food, medicine, cosmetics, and petrochemicals. However, the occurrence of the oxidation reaction is accompanied by a strong exothermic phenomenon, and improper control can easily lead to safety problems and even explosions. The realization of an environmentally friendly oxidation reaction is a key industrial milestone. The unique structural characteristics of microreactors result in good mass and heat transfer performance, precise control of the reaction temperature, reduced risk of explosion, improved safety production and selectivity of products. These unique advantages of the microreactor determine its significant application value in oxidation reactions. In this paper, the research progress of several typical oxidation reactions, including alkane oxidation, alcohol oxidation, aldosterone oxidation, aromatics oxidation and olefin oxidation combined with microreactors, is reviewed systematically.

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39

Paryzek, Zozislaw, and Jacek Martynow. "Tetracyclic triterpenes. X. Solvent effect in reactions of tetrasubstituted triterpenoidal olefins with ozone. An allylic oxidation." Canadian Journal of Chemistry 66, no. 9 (September 1, 1988): 2130–36. http://dx.doi.org/10.1139/v88-338.

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The highly hindered 8,9 double bond in lanostane derivatives was found susceptible to oxidation with ozone. The reaction depends on the polarity of the solvent. It is proposed that the structure of the initial complex formed between the olefin and ozone is influenced by the reaction medium. Reaction of 3β-acetoxy-5α-lanost-8-ene with ozone gives 8α, 9α-epoxide in methylene chloride, while 3β-acetoxy-5α-lanost-8-en-7-one, an allylic oxidation product, is the main compound formed in ethyl acetate.

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40

Quiller, Ryan G, Xiaoying Liu, and Cynthia M Friend. "Mechanistic Insights into Selectivity Control for Heterogeneous Olefin Oxidation: Styrene Oxidation on Au(111)." Chemistry - An Asian Journal 5, no. 1 (January 4, 2010): 78–86. http://dx.doi.org/10.1002/asia.200900399.

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41

Sales, Rita N., Samantha K. Callear, Pedro D. Vaz, and Carla D. Nunes. "Substrate–Solvent Crosstalk—Effects on Reaction Kinetics and Product Selectivity in Olefin Oxidation Catalysis." Chemistry 3, no. 3 (July 19, 2021): 753–64. http://dx.doi.org/10.3390/chemistry3030054.

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In this work, we explored how solvents can affect olefin oxidation reactions catalyzed by MCM-bpy-Mo catalysts and whether their control can be made with those players. The results of this study demonstrated that polar and apolar aprotic solvents modulated the reactions in different ways. Experimental data showed that acetonitrile (aprotic polar) could largely hinder the reaction rate, whereas toluene (aprotic apolar) did not. In both cases, product selectivity at isoconversion was not affected. Further insights were obtained by means of neutron diffraction experiments, which confirmed the kinetic data and allowed for the proposal of a model based on substrate–solvent crosstalk by means of hydrogen bonding. In addition, the model was also validated in the ring-opening reaction (overoxidation) of styrene oxide to benzaldehyde, which progressed when toluene was the solvent (reaching 31% styrene oxide conversion) but was strongly hindered when acetonitrile was used instead (reaching only 7% conversion) due to the establishment of H-bonds in the latter. Although this model was confirmed and validated for olefin oxidation reactions, it can be envisaged that it may also be applied to other catalytic reaction systems where reaction control is critical, thereby widening its use.

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42

Fajkoš, Jan, та Jiří Joska. "Solvolytic rearrangements in 4β,5-cyclopropano-5β-androstane-3β,17β,19-triol 3-acetate 17-benzoate 19-p-toluenesulfonate". Collection of Czechoslovak Chemical Communications 54, № 3 (1989): 751–59. http://dx.doi.org/10.1135/cccc19890751.

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The title tosylate V was prepared from the tosylate III by Simmons-Smith methylenation. Its acetolysis afforded three products with modified steroid skeletons: The diene VIII, the olefin XI, and the pentacyclic diacetate XIII. The 3-oxo derivatives XIV, XVI, XVII, and XIX-compounds of potentional biological interest-were prepared as follows: Oxidation of the monoacetate X followed by hydrolysis yielded the testosterone analogue XIV and oxidation of the diol IX gave the dione XVI. Using similar reaction sequence the triol diester XII afforded the oxo compounds XVII and XIX.

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43

Pliss, E. M., V. A. Machtin, I. V. Tikhonov, A. V. Sirik, A. M. Grobov, and O. A. Yasinsky. "Catalytic inhibition of olefin oxidation with Mn and Cu compounds." Russian Chemical Bulletin 70, no. 10 (October 2021): 2027–30. http://dx.doi.org/10.1007/s11172-021-3312-2.

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44

Govindan, S. V., and P. L. Fuchs. "Regiospecific quassinoidal A-ring synthesis via an olefin oxidation strategy." Journal of Organic Chemistry 53, no. 11 (May 1988): 2593–97. http://dx.doi.org/10.1021/jo00246a036.

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45

MORI, Tomonori, Motowo YAMAGUCHI, and Takamichi YAMAGISHI. "Hydrogen Peroxide Oxidation of Olefin Catalyzed by Polyaminopolycarboxylatoruthenium(III) Complexes." NIPPON KAGAKU KAISHI, no. 5 (1997): 329–34. http://dx.doi.org/10.1246/nikkashi.1997.329.

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46

Birnbaum, Eva R., Jay A. Labinger, John E. Bercaw, and Harry B. Gray. "Catalysis of aerobic olefin oxidation by a ruthenium perhaloporphyrin complex." Inorganica Chimica Acta 270, no. 1-2 (April 1998): 433–39. http://dx.doi.org/10.1016/s0020-1693(97)06000-3.

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47

Kato, Tadahiro, Toshifumi Hirukawa, and Kohji Namiki. "Selective terminal olefin oxidation of n-3 polyunsaturated fatty acids." Tetrahedron Letters 33, no. 11 (March 1992): 1475–78. http://dx.doi.org/10.1016/s0040-4039(00)91651-4.

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48

Brown, John M., Robert A. John, and Andrew R. Lucy. "Observations on olefin oxidation by neutral and cationic phosphineiridium complexes." Journal of Organometallic Chemistry 279, no. 1-2 (January 1985): 245–57. http://dx.doi.org/10.1016/0022-328x(85)87022-4.

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49

Nair, Vipin A., M. M. Suni та K. Sreekumar. "Polystyrene-supported β-diketone-linked palladium complexes for olefin oxidation". Designed Monomers and Polymers 6, № 1 (січень 2003): 81–89. http://dx.doi.org/10.1163/156855503321127556.

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50

Páez-Mozo, E., N. Gabriunas, R. Maggi, D. Acosta, P. Ruiz, and B. Delmon. "Selective olefin oxidation with cobalt phthalocyanine encapsulated in Y-zeolite." Journal of Molecular Catalysis 91, no. 2 (July 1994): 251–58. http://dx.doi.org/10.1016/0304-5102(94)00027-1.

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