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Littérature scientifique sur le sujet « Alkane oxygenation »

Auteur : Grafiati

Publié le 9 mars 2023

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Articles de revues sur le sujet "Alkane oxygenation"

Shul'pin, Georgiy B., Alexander E. Shilov et Georg Süss-Fink. « Alkane oxygenation catalysed by gold complexes ». Tetrahedron Letters 42, n^o 41 (octobre 2001) : 7253–56. http://dx.doi.org/10.1016/s0040-4039(01)01517-9.

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Shul'pin, Georgiy B. « Alkane Oxygenation with Hydrogen Peroxide Catalysed by Soluble Derivatives of Nickel and Platinum ». Journal of Chemical Research 2002, n^o 7 (juillet 2002) : 351–53. http://dx.doi.org/10.3184/030823402103172257.

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Various alkanes can be oxidised by hydrogen peroxide in acetonitrile solution at 70°C if Ni(ClO4)2 (in the presence of 1,4,7-trimethyl-1,4,7-triazacyclononane) or H2PtCl6 are used as catalysts; whereas the nickel-catalysed reaction seems to proceed via attack of hydroxyl radicals on an alkane, the oxidation in the presence of platinum occurs possibly with participation of oxo or peroxo derivatives of this metal.

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Julsing, Mattijs K., Manfred Schrewe, Sjef Cornelissen, Inna Hermann, Andreas Schmid et Bruno Bühler. « Outer Membrane Protein AlkL Boosts Biocatalytic Oxyfunctionalization of Hydrophobic Substrates in Escherichia coli ». Applied and Environmental Microbiology 78, n^o 16 (8 juin 2012) : 5724–33. http://dx.doi.org/10.1128/aem.00949-12.

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ABSTRACTThe outer membrane of microbial cells forms an effective barrier for hydrophobic compounds, potentially causing an uptake limitation for hydrophobic substrates. Low bioconversion activities (1.9 U gcdw−1) have been observed for the ω-oxyfunctionalization of dodecanoic acid methyl ester by recombinantEscherichia colicontaining the alkane monooxygenase AlkBGT ofPseudomonas putidaGPo1. Using fatty acid methyl ester oxygenation as the model reaction, this study investigated strategies to improve bacterial uptake of hydrophobic substrates. Admixture of surfactants and cosolvents to improve substrate solubilization did not result in increased oxygenation rates. Addition of EDTA increased the initial dodecanoic acid methyl ester oxygenation activity 2.8-fold. The use of recombinantPseudomonas fluorescensCHA0 instead ofE. coliresulted in a similar activity increase. However, substrate mass transfer into cells was still found to be limiting. Remarkably, the coexpression of thealkLgene ofP. putidaGPo1 encoding an outer membrane protein with so-far-unknown function increased the dodecanoic acid methyl ester oxygenation activity of recombinantE. coli28-fold. In a two-liquid-phase bioreactor setup, a 62-fold increase to a maximal activity of 87 U gcdw−1was achieved, enabling the accumulation of high titers of terminally oxyfunctionalized products. Coexpression ofalkLalso increased oxygenation activities toward the natural AlkBGT substrates octane and nonane, showing for the first time clear evidence for a prominent role of AlkL in alkane degradation. This study demonstrates that AlkL is an efficient tool to boost productivities of whole-cell biotransformations involving hydrophobic aliphatic substrates and thus has potential for broad applicability.

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Shul’pin, Georgiy B., Tawan Sooknoi, Vladimir B. Romakh, Georg Süss-Fink et Lidia S. Shul’pina. « Regioselective alkane oxygenation with H2O2 catalyzed by titanosilicalite TS-1 ». Tetrahedron Letters 47, n^o 18 (mai 2006) : 3071–75. http://dx.doi.org/10.1016/j.tetlet.2006.03.009.

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Shul’pin, Georgiy B., Camilla C. Golfeto, Georg Süss-Fink, Lidia S. Shul’pina et Dalmo Mandelli. « Alkane oxygenation with H2O2 catalysed by FeCl3 and 2,2′-bipyridine ». Tetrahedron Letters 46, n^o 27 (juillet 2005) : 4563–67. http://dx.doi.org/10.1016/j.tetlet.2005.05.007.

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Company, Anna, Julio Lloret, Laura Gomez et Miquel Costas. « ChemInform Abstract : Alkane C-H Oxygenation Catalyzed by Transition Metal Complexes ». ChemInform 44, n^o 11 (8 mars 2013) : no. http://dx.doi.org/10.1002/chin.201311257.

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Sahoo, Prakash C., Amardeep Singh, Manoj Kumar, R. P. Gupta, D. Bhattacharyya et S. S. V. Ramakumar. « Photosensitized biohybrid for terminal oxygenation of n-alkane to α, ω-dicarboxylic acids ». Molecular Catalysis 535 (janvier 2023) : 112889. http://dx.doi.org/10.1016/j.mcat.2022.112889.

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Barloy, Laurent, Pierrette Battioni et Daniel Mansuy. « Manganese porphyrins supported on montmorillonite as hydrocarbon mono-oxygenation catalysts : particular efficacy for linear alkane hydroxylation ». Journal of the Chemical Society, Chemical Communications, n^o 19 (1990) : 1365. http://dx.doi.org/10.1039/c39900001365.

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Guisado-Barrios, Gregorio, Alexandra M. Z. Slawin et David T. Richens. « Iron complexes of new hydrophobic derivatives of tris(2-pyridylmethyl)amine : synthesis, characterization, and catalysis of alkane oxygenation by H2O2 ». Journal of Coordination Chemistry 63, n^o 14-16 (20 juillet 2010) : 2642–58. http://dx.doi.org/10.1080/00958972.2010.506216.

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Sutradhar, Manas, Nikita V. Shvydkiy, M. Fátima C. Guedes da Silva, Marina V. Kirillova, Yuriy N. Kozlov, Armando J. L. Pombeiro et Georgiy B. Shul'pin. « A new binuclear oxovanadium(v) complex as a catalyst in combination with pyrazinecarboxylic acid (PCA) for efficient alkane oxygenation by H2O2 ». Dalton Transactions 42, n^o 33 (2013) : 11791. http://dx.doi.org/10.1039/c3dt50584g.

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Thèses sur le sujet "Alkane oxygenation"

SUAREZ, BERTOA RICARDO. « Sustainable procedures in organic synthesis ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2009. http://hdl.handle.net/10281/7474.

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O-acyl-N-benzyllactamides are obtained in good yield by reaction of 4-benzyl-5-methyl-1,3-oxazolidine-2,4-diones with Grignards reagents and with lithium alkyls. Three alkanes and two ethers were oxidised with ozone in dichloromethane solution or in aqueous pH 3 suspension. Cyclodecane and cyclododecane were converted into the corresponding cycloalkanones. n-decane was converted into a mixture of isomeric n-decanones and carboxylic acids. An ester was formed from the ethers. Hence, one of the methylene groups of these substrates is generally converted into a carbonyl group. Some of these reactions have preparative value. The oxidation of naphthalene in dichloromethane or acetonitrile with excess ozone gives phthalic aldehyde, 2-formyl benzoic acid and phthalic anhydride. Small amounts of the (E)- and (Z)-isomer of 3-phenyl-(2-formyl)-propenal and are also observed in some cases. The reaction is faster in acetonitrile than in dichloromethane owing to the higher solubility of ozone in the former solvent. The reaction is faster on lowering the temperature because of the increase of the concentration of ozone in solution at lower temperature. With a 1:1 or a 1:2 naphthalene:ozone ratio high conversion and low selectivity for the anhydride is observed. The ozonation of cyclohexane in dichloromethane or acetonitrile gives cycloxexanone, cyclohexanol and acidic material. The influence of solvent, reactant concentration, amount of ozone, temperature, reaction time is studied. A reaction mechanism is proposed based on the results of a simulation of the reaction energetics. The ozonation of N-phenylmorpholine in dichloromethane or acetonitrile produced a lactame and a diformylderivative. These products derive from the attack of ozone at the heterocyclic ring. The reaction mechanism has been investigated by DFT calculations which show that the reaction occurs through the insertion of ozone at the carbon-hydrogen bond of a methylenic group of the morpholine ring. The regioselectivity is due to the to the significantly lower energy barrier calculated for the attack of ozone in α to nitrogen than in α to oxygen. Also, the energy barrier decreases with increasing the polarity of the solvent, accounting for the higher reaction rate observed for the reaction carried out in acetonitrile than in dichloromethane. The ozonation of trans- and cis-decalin in dichloromethane or acetonitrile gives the corresponding 9-hydroxydecalinns, 2- and 3-decalones and acidic material. The influence of solvent, reactant concentration, amount of ozone, temperature, reaction time is studied. A reaction mechanism is proposed based on the results of a simulation of the reaction energetics. The N,N bis(salicylidene)ethylenediaminocobalt(II) catalysed oxidative carbonylation of para-substituted aromatic primary amines at 100 °C in methanol gives carbamates in high yields. In presence of excess dimethylamine also N-aryl-N’,N’-dimethylureas are formed. In methylene chloride moderate yields in isocyanate are obtained. 1-methylbenzylamine gives the carbamate and the urea in high yield. i-propylamine gives only the urea. An α-aminoalcohol gives a 1,3-oxazolidin-2-one. Aliphatic secondary amines react faster and give carbamates in methanol and ureas in methylene chloride. The turnover frequency is also measured in two cases.

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Guisado, Barrios Gregorio. « Towards the development of selective hydrocarbon oxygenation catalysts ». Thesis, University of St Andrews, 2010. http://hdl.handle.net/10023/925.

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The synthesis of pure tris(6-hydroxymethyl-2-pyridylmethyl)amine (H₃L₁₁) is reported for the first time. New complexes of H₃L₁₁ with copper(II), manganese(II) and iron(III) have been characterised by X-ray crystallography. Linear [Fe₃(L₁₁)₂](ClO₄)₃ reveals the tightest Fe-O-Fe angle (87.6°) and shortest Fe...Fe distance (2.834 Å) presently found for a weakly antiferromagnetically-coupled high spin alkoxide-bridged polyiron(III) system. H₃L₁₁ provides a route to various hydrophobic peralkylated TPA ligand derivatives for creating a hydrophobic pocket for the assembly of iron catalysts for the novel 1-hydroxylation of n-alkanes. New 6-py substituted TPA ligands containing methyl (L₁₅) and n-octyl (L₁₆) ether linkages were synthesised via alkylation. Two further novel 6-py substituted ligands were synthesized incorporating n-hexyl substituents on one (L₂₁) and two (L₂₂) of the py moieties. Here a urea spacer group was used to promote hydrogen–bond assisted heterolytic O-O cleavage (generation of the potent FeV=O oxidant) within the hydroxoperoxoiron(III) precursor. High spin [FeII(L)(CH₃CN)[subscript(x)]](CF₃SO₃)₂ complexes (x = 0–2, L = L₁₅,₁₆,₂₁,₂₂) were characterised in solution by ¹H NMR. The structure of [Fe(L₂₂)](CF₃SO₃)₂ reveals a distorted iron(II) centre bound to four N atoms and two urea carbonyls. Iron(II) complexes of H₃L₁₁, L₁₅,₁₆,₂₁,₂₂ and tris(6-Br)-TPA (L₂₄), were investigated for catalysis of the oxygenation of cyclohexane by H₂O₂. Reaction of the iron(II) complexes with H₂O₂ and [superscript(t)]BuOOH was followed by time-resolved EPR and UV-VIS spectrophotometry. A correlation between the observed catalytic activity and the nature of the FeIII(L)-OOR intermediates generated is apparent. A convenient ‘one-pot’ synthesis of benzene-1,3,5-triamido-tris(l-histidine methyl ester) is reported along with attempts at preparing N,N’-bis(pyridylmethyl)-1,3- diaminopropane-2-carboxylic acid (L₂₅), a new water soluble pyridine-amine ligand. The final demetallation step resulted in ligand hydrolysis to the novel amino acid; 1,3-diaminopropane- 2-carboxylic acid which was characterised as its HCl salt by X-ray crystallography.

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Schneider, Ludovic. « Systèmes hybrides photosensibilisateur-laccase pour la catalyse d'oxydation de composés organiques ». Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4372.

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Les laccases sont des enzymes de type oxydase, réalisant de manière efficace la réduction du dioxygène en eau. Des études réalisées au laboratoire ont permis de montrer que l’irradiation sous atmosphère inerte d’un système de type, EDTA/[Ru(bpy)3]2+/laccase, conduisait à la photoréduction de l’enzyme via la formation d'une espèce [Ru(bpy)3]2+*. La substitution de l’EDTA par un alcène de type p-styrène sulfonate conduit également à la photoréduction de l’enzyme. L'ouverture à l'air du système permet une consommation d’oxygène concomitante à la détection par RMN de produits d’oxydation tels que l’époxyde, le diol et le p-benzaldéhyde sulfonate. L’influence de la concentration des différents partenaires, de la source d’irradiation et du pH sur l’efficacité de cette réaction a été évaluée. D’autres alcènes tels que le styrène, le cyclohéxène ou le cyclooctène sont également substrats. Le marquage isotopique en présence soit d'H218O soit d'18O2 ainsi que l’utilisation de générateurs d’espèces réactives de l’oxygène, ont permis de proposer un mécanisme majoritaire où l’espèce RuIII, photoproduite avec l'assistance de la laccase, pourrait arracher un électron du substrat qui à son tour réagirait avec le dioxygène présent dans le milieu pour conduire aux produits observés. D’autres complexes photoactivables à base de ruthénium ou de manganèse ont également été employés. Afin d’aborder le contrôle de la réactivité, le greffage covalent d’un photosensibilisateur à base de ruthénium sur une lysine unique à proximité du site d'oxydation des substrats de l'enzyme a été effectué
Laccases are oxidases that efficiently perform the reduction of dioxygen into water. Studies in the laboratory have allowed to show that irradiation under inert atmosphere of a EDTA/[Ru(bpy)3]2+/laccase system, lead to the photoreduction of the enzyme via the irradiation of [Ru(bpy)3]2+*. The substitution of EDTA by the alkene p-styrene sulfonate results similarly in a photoreduction of the enzyme. Opening the system to air allows a dioxygen consumption with a simultaneous detection of oxidation products such as the epoxide, diol and p-benzaldehyde sulfonate detected by NMR. The influence of the concentration of the partners, the irradiation source and pH on the efficiency of the reaction was evaluated. Other alkenes such as styrene, cyclohexene and cyclooctene are also substrates. Isotopic labeling experiments in the presence of either H218O or 18O2, as well as the use of reactive oxygen species generators, allowed us to propose a main mechanism where the laccase assisted RuIII photogenerated specie would withdraw an electron from the substrate which in turn would react with dioxygen to yield the products observed. Other ruthenium and manganese photosensitizers were also used. To address the control of the reactivity, a covalent grafting of a ruthenium photosensitizer, on a unique lysine nearby the substrate oxidation site of the laccase was done

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Tseng, Tzu-Hsien, et 曾資賢. « Non-Heme Iron Model Study for Alkane C-H Oxygenation ». Thesis, 2014. http://ndltd.ncl.edu.tw/handle/90344934585443563899.

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碩士
國立中興大學
化學系所
102
Recently, the energy consumption is the urgent issue for scientists to devote great effort to solve the problems. The upper layer of petroleum which is abundant with methane comes with low remunerative value. Nowadays, a costly two-stage process is used to transform methane to methanol under a hard condition with very low yield. The qualities such as transportation, safety, storage, and commercial value of methanol are much advantageous than methane. However, the shortcoming is that there would be huge amount of energy consumption during the process of transformation. Methane monooxygenase (MMOs) which are inclusive of particular MMO (pMMO) and soluble MMO (sMMO) achieve this chemistry efficiently under ambient conditions. Those two MMOs carry out the oxidation from methane to methanol. The report refers to the sMMO system and synthesis of complexes which are similar to the ligand environment and active center of MMO and possess the unprecedented ability of oxidation. We announced here that the treatment of 1 equivalence complex and 1 equivalent of oxidant to cyclohexane, substrate for catalysis, could oxidize cyclohexane to cyclohexanol and cyclohexaone successfully under the normal pressure and temperature. The announcement mentioned above is based on the known criteria of cyclohexane C-H bond dissociation energy ( BDEC-H = 99.3 kcal/mol) which closely approximates to methane ( BDEC-H = 104 kcal/mol).

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簡佑芩. « (I)Structrual and Functional Models for the Trinuclear Copper Clusters of the Particulate Methane Monooxygenase (II)Monooxygenase-like Oxygenation of Alkane Molecules Catalyzed by Trinuclear Manganese Complex ». Thesis, 2010. http://ndltd.ncl.edu.tw/handle/33409504356936432529.

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碩士
國立臺灣師範大學
化學系
99
In first study, a new modified trinuclear copper complex, [CuICuICuI(7-dipy)](BF4) (2), was first employed as a catalyst to oxidize the CH bonds of cyclohexane (CH BDE is 99.3 kcal mol-1). ESI-MS spectra demonstrate that the oxygenation of [CuICuICuI(7-dipy)](BF4) (2)either by dioxygen will obtain a stable [CuIICuII(-O)CuII(7-dipy)](BF4 )2(3) complex. The catalysis of CH bond oxygenation of cyclohexane was carried out under room temperature in the presence of 50 equivalents of oxidant, and a product mixture of cyclohexanol and cyclohexanone were observed with 34% conversion according to the consuming of the oxidant by the quantitative GC-MS analysis. However, there is nearly no reaction by employing [CuIICuII(-O)CuII(7-dipy)](BF4)2 (3) complex instead of [CuICuICuI(7-dipy)](BF4) (2). This tricopper complex is a quite robust catalyst because most the remainders after the catalytic reaction are in the form of [CuIICuII(-O)CuII(7-dipy)](BF4)2 (3)evidenced by ESI-MS spectra. In second study, the same 7-dipy ligand was also adopted in the synthesis of trinuclear manganese complex. A first trimanganese complex [MnII(OAc)2MnII(-OAc)2MnII(7-dipy)] (2) was first synthesized as a precursor for the high-valent manganese species. Further oxidation of [MnII(OAc)2MnII(-OAc)2MnII(7-dipy)] (2) by treating two equivalents of TBHP (tert-butylhydroperoxide) is able to obtain a 16-line characteristic EPR spectrum with gx= 2.006, gy= 1.998, gz= 1.985, AIII xx=-16.3 mT, AIII yy= -11.7 mT, AIII zz= -16.2 mT, AIV xx= 8.2 mT, AIV yy= 8.0 mT, AIV zz= 7.4 mT acquired by simulation, which is postulated as a active intermediate, [MnIIIMnIII(-O)2MnIV(7-dipy)]4+ (3). While excess of TBHP up to 15 equivalents were added, and the 16-line EPR spectra still remain unchanged. [MnIIIMnIII(-O)2MnIV(7-dipy)]4+ (3) is able to catalyze the oxidation of CH bonds of cyclohexane (CH BDE is 99.3 kcal mol-1) to a mixture of cyclohexanol and cyclohexanone, CH bonds of n-hexane in the C-2 and C-3 position (CH BDE is 98 kcal mol-1 and 99.1 kcal mol-1, respectively) to a mixture of 2-hexanol, 3-hexanol, 2-hexanone and 3-hexanone. Except the CH bond oxidation in the secondary carbon atom position, ethane molecule which merely has primary CH bonds (CH BDE is 101 kcal mol-1) was applied as the substrate, and the suspected acetic acid product involving 6 oxidation equivalents was found. Ethanol molecule (CH BDE is 95.6 kcal mol-1) as the substrate was also oxidized in the same catalysis to form the acetic acid product, providing the support for the oxidation of ethane molecule.

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Teasley, Mark Frederick. « The cation radical chain oxygenation of alkenes and dienes, the physical properties of alkene, diene, and peroxide cation radicals, and the crisscross dimerization of a dendralene ». 1987. http://catalog.hathitrust.org/api/volumes/oclc/16319176.html.

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Chapitres de livres sur le sujet "Alkane oxygenation"

Company, Anna, Julio Lloret, Laura Gómez et Miquel Costas. « Alkane C–H Oxygenation Catalyzed by Transition Metal Complexes ». Dans Catalysis by Metal Complexes, 143–228. Dordrecht : Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-90-481-3698-8_5.

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Baader, W. J., et E. L. Bastos. « Thiol–Alkene Co-oxygenation ». Dans Peroxides, Inorganic Esters (RO-X, X=Hal, S, Se, Te, N), 1. Georg Thieme Verlag KG, 2009. http://dx.doi.org/10.1055/sos-sd-038-00420.

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Alberti, M. N., M. D. Tzirakis et M. Orfanopoulos. « Thiol–Alkene Co-oxygenation ». Dans Peroxides, Inorganic Esters (RO-X, X=Hal, S, Se, Te, N), 1. Georg Thieme Verlag KG, 2009. http://dx.doi.org/10.1055/sos-sd-038-00462.

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Taber, Douglass F. « The Trost Synthesis of (-)-Pseudolaric Acid B ». Dans Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0085.

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(-)-Pseudolaric acid B 3, isolated from the bark of the golden larch Pseudolarix kaempferi, shows potent antifungal activity. A key step in the total synthesis of 3 described (J. Am. Chem. Soc. 2008 , 130 , 16424) by Barry M. Trost of Stanford University was the free radical cyclization of 1 that established the angular ester and the trans ring fusion of 2 and thus of 3. To prepare the bicyclic skeleton of 1, the authors envisioned the Rh-mediated intramolecular addition of the alkyne of 11 to the alkenyl cyclopropane. The acyclic centers of 11 were established by Noyori hydrogenation of (equilibrating) racemic 4. One enantiomer reduced much more quickly than the other, leading to 5. The absolute configuration of the cyclopropane was set by Charette cyclopropanation of the monosilyl ether of the inexpensive diol 8. The two components were then coupled using a Corey-Schlosser protocol. Alkylation of the ylide 10 with 7 gave a new phosphonium salt, which in situ was deprotonated and condensed with the aldehyde 9 . The resulting betaine was deprotonated and quenched, then exposed again to base to give the trans alkene 11. It is important in this procedure to use PhLi as the base, because the alkyl lithium can displace the alkyl group on phosphorus. The product from Ru-catalyzed cyclization was the expected 1,4-diene 12 . Fortunately, it was found that TBAF desilylation led to concomitant alkene migration, to give the more stable conjugated diene 13. Selective epoxidation of the more electron-rich alkene fol lowed by exposure to strong base then delivered 14 , with the requisite angular oxygenation established. Pseudolaric acid B 3 would be derived from cyclization of the selenocarbonate of a tertiary alcohol. In fact, however, attempted cyclization of such selenocarbonates led only to decarboxyation and reduction. Even with the selenocarbonate 1 prepared from the secondary alcohol, the cyclization to 2 required careful optimization, including using not AIBN but azobis(dicyclohexylcarbonitrile) as the radical initiator. Acetylide addition to the ketone 15 could be effected with high diastereocontrol, but lactone construction proved elusive. Alkaline conditions led quickly to addition of the angular hydroxyl to the activated alkene in the seven-membered ring.

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Baader, W. J., et E. L. Bastos. « Singlet Oxygenation of Alkenes ». Dans Peroxides, Inorganic Esters (RO-X, X=Hal, S, Se, Te, N), 1. Georg Thieme Verlag KG, 2009. http://dx.doi.org/10.1055/sos-sd-038-00354.

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Tidwell, T. T. « Monoarylketenes by Ruthenium-Catalyzed Alkyne Oxygenation ». Dans Three Carbon-Heteroatom Bonds : Thio-, Seleno-, and Tellurocarboxylic Acids and Derivatives ; Imidic Acids and Derivatives ; Ortho Acid Derivatives, 1. Georg Thieme Verlag KG, 2006. http://dx.doi.org/10.1055/sos-sd-023-00412.

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Huybrechts, D. R. C., Ph L. Buskens et P. A. Jacobs. « Alkane Oxygenations By H2O2 On Titanium Silicalite ». Dans New Developments in Selective Oxidation by Heterogeneous Catalysis, 21–31. Elsevier, 1992. http://dx.doi.org/10.1016/s0167-2991(08)61655-9.

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Malacria, M., C. Aubert et J. L. Renaud. « Cobalt(II)-Mediated Aerobic Oxygenation of Alkenes ». Dans Compounds with Transition Metal-Carbon pi-Bonds and Compounds of Groups 10-8 (Ni, Pd, Pt, Co, Rh, Ir, Fe, Ru, Os), 1. Georg Thieme Verlag KG, 2001. http://dx.doi.org/10.1055/sos-sd-001-00385.

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Nishinaga, Akira, Kazushige Maruyama, Takahiro Mashino, Kohei Yoda et Hiromitsu Okamoto. « Cobalt-Schiff Base Complex Promoted Oxygenation of Alkynes ». Dans Dioxygen Activation and Homogeneous Catalytic Oxidation, Proceedings of the Fourth International Symposium on Dioxygen Activation and Homogeneous Catalytic Oxidation, 93–102. Elsevier, 1991. http://dx.doi.org/10.1016/s0167-2991(08)62823-2.

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Taber, Douglass F. « The Sato/Chida Synthesis of Paclitaxel (Taxol®) ». Dans Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0104.

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Paclitaxel (Taxol®) 3 is widely used in the clinical treatment of a variety of cancers. Takaaki Sato and Noritaka Chida of Keio University envisioned (Org. Lett. 2015, 17, 2570, 2574) establishing the central eight-membered ring of 3 by the SmI2-mediated cyclization of 1 to 2. The starting point for the synthesis was the enantiomerically-pure enone 5, prepared from the carbohydrate precursor 4. Conjugate addition to 5 proceeded anti to the benzyloxy substituent to give, after trapping with formaldehyde and protection, the ketone 6. Reduction and protection followed by hydroboration led to 7, that was, after protection and deprotection, oxidized to 8. The second ring of 3 was added in the form of the alkenyl lithium derivative 9, prepared from the trisylhydrazone of the corresponding ketone. Hydroxyl-directed epoxidation of 10 proceeded with high facial selectivity, leading, after reduction and protection, to the cyclic carbonate 11. Allylic oxidation converted the alkene into the enone, while at the same time oxidizing the benzyl protecting group to the benzoate, to give 12. Reduction of the ketone 12 led to a mixture of diastereomers. In practice, only one of the diastereomers of 1 cyclized cleanly to 2, as illustrated, so the undesired diastereomer from the NaBH4 reduction was oxidized back to the enone for recycling. For convenience, only one of the diastereomers of 2 was carried forward. To establish the tetrasubstituted alkene of 3, the alkene of 2 was converted to the cis diol and on to the bis xanthate 13. Warming to 50°C led to the desired tetrasubstituted alkene, sparing the oxygenation that is eventually required for 3. For convenience, to intercept 16, the intermediate in the Takahashi total synthesis, both xanthates were eliminated to give 14. Hydrogenation removed the disubstituted alkene, and also deprotected the benzyl ether. Oxidation followed by Peterson alkene formation led to 15, that was carried on to the Takahashi intermediate 16 using the now-standard protocol for oxetane construction. It is a measure of the strength of the science of organic synthesis that Masahisa Nakada of Waseda University also reported (Chem. Eur. J. 2015, 21, 355) an elegant synthesis of 3 (not illustrated).

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Actes de conférences sur le sujet "Alkane oxygenation"

Tagmatarchis, Nikos. « Photosensitized oxygenation of alkenes in the presence of bisazafullerene (C[sub 59]N)[sub 2] and hydroazafullerene C[sub 59]HN ». Dans NANONETWORK MATERIALS : Fullerenes, Nanotubes, and Related Systems. AIP, 2001. http://dx.doi.org/10.1063/1.1420140.

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