3112-85-4Relevant articles and documents
1,1′-Binaphthyl-2-methylpyridinium-based peroxophosphotungstate salts: Synthesis, characterization and their use as oxidation catalysts
Jahier, Claire,Felpin, Francois-Xavier,Meliet, Catherine,Agbossou-Niedercorn, Francine,Hierso, Jean-Cyrille,Nlate, Sylvain
, p. 5148 - 5155 (2009)
A series of 1,1'-binaphthyl-2-methylammonium and pyridinium salts 6, 7, and 8 was synthesized through the coupling reaction of 2-(bromomethyl)-1,1'- binaphthalene (5) with the dendritic tetraallyl pyridinedicarbinol dendron 2 as well as triethylamine and 4-tert-butylpyridine. Tetraallyl pyridinedicarbinol dendron 2 was prepared by allylation of commercially available diethyl pyridine-3,5-dicarboxylate (1). The allylation of 2 with, allyltrimethylsilane in the presence of boron trifluoride was unsuccessful, as tetraallyl pyridinedicarbinol trifluoroboron adduct 3 was obtained instead of expected hexaallylpyridine compound 4. The catalytic hydrogenation of allyl groups of the ammonium salt of 2, namely, tetraallyl 1,1'-binaphthyl-2-methylpyridinium salt 6, successfully led to the corresponding tetra-n-propyl 1,1'-binaphthyl-2- methylpyridinium salt 9. The reaction between salts 7, 8, and 9 and the heteropolyacid H3PW12O40 in the presence of a large excess of hydrogen peroxide afforded the corresponding 1,1'-binaphthyl-2-methylammonium-based polyoxometalate salts 10, 11, and 12, which, contain a catalytically active trianionic [H3PW 12O4O]3- in the core. These binaphthyl-POM salts are soluble in commonly used organic solvents, and their IR and 31P NMR spectroscopic and elemental analysis data indicate the presence of the POM unit in the frameworks. These POM hybrids are efficient, recoverable, and reusable catalysts in the oxidation of thioanisole, cyclooctene, and cyclohexanol, with H2O2 as the oxidant. A study of the countercation effects indicated that the reaction kinetics and the selectivity are sensitive to the structure of the cation. Two cycles of catalytic reactions were performed without a discernible loss in activity. Wiley-VCH Verlag GmbH & Co. KGaA.
Oxidovanadium(V) complexes containing hydrazone based O,N,O-donor ligands: Synthesis, structure, catalytic properties and theoretical calculations
Hosseini-Monfared, Hassan,Bikas, Rahman,Mahboubi-Anarjan, Parisa,Blake, Alexander J.,Lippolis, Vito,Arslan, N. Burcu,Kazak, Canan
, p. 90 - 102 (2014)
Two new mono oxidovanadium(V) complexes, [VOL1(OEt)] (1) and [VOL2(OMe)] (2), of the tridentate Schiff base hydrazone-type O,N,O-donor ligands H2L1 and H2L2, obtained by monocondensation of 3-hydroxy-2-naphthohydrazide with 5-bromo-2-hydroxybenzaldehyde and benzoylacetone, respectively, have been synthesized starting from VO(acac)2 [H2L1 = (E)-N′-(5-bromo-2-hydroxybenzylidene)-3-hydroxy-2-naphthohydrazide; H 2L2 = (E)-3-hydroxy-N′-((Z)-4-hydroxy-4-phenylbut-3- en-2-ylidene)-2-naphthohydrazide]. Single-crystal X-ray structure analysis revealed for both complexes a slightly distorted square-based pyramidal NO 4 coordination environment around the metal centre, with the aroylhydrazone Schiff bases acting as O,N,O-tridentate, dinegative ligands. The complexes were also characterized by spectroscopic methods in the solid state (IR) and in solution (UV-Vis, 1H NMR) and by cyclic voltammetric experiments in DMSO, and their properties were interpreted by means of DFT theoretical calculations. The catalytic potential of these complexes has been tested for the oxidation of thioanisol using H2O2 as the terminal oxidant. The effects of various parameters, including the molar ratio of oxidant to substrate, the temperature and the solvent, have been studied. Both complexes showed superabundant catalytic activity in the oxidation of thioanisol at room temperature with excellent conversions.
REACTION OF SINGLET OXYGEN WITH INDANONE PHOSPHAZINE: FORMATION OF KETONE AND LACTONE
Akasaka, Takeshi,Sato, Rikiya,Miyama, Yukiyo,Ando, Wataru
, p. 843 - 846 (1985)
Photooxygenation of 1,1,3,3-tetramethyl-2-indanone triphenylphosphazine afforded, in addition to the parent indanone and triphenylphosphine oxide, 2,2,5,5-tetramethyl-3,4-benzo-3-penten-5-olide from a carbonyl oxide intermediate and also gave light emission.
ONE ELECTRON TRANSFER MECHANISM IN THE ENZYMATIC OXYGENATION OF SULFOXIDE TO SULFONE PROMOTED BY A RECONSTITUTED SYSTEM WITH PURIFIED CYTOCHROME P-450
Watanabe, Yoshihito,Iyanagi, Takashi,Qae, Shigeru
, p. 533 - 536 (1982)
A kinetic study on enzymatic S-oxygenation of sulfoxides to sulfones was carried out by a reconstituted system with purified cytochrome P-450.A linear correlation observed between log(Vmax)'s and the one-electron oxidation potentials of sulfoxides suggests that the oxygenation of sulfoxides proceeds via one electron transfer process to the active "oxenoid" intermediate of the enzyme.
A method for the conversion of sulfoximines to sulfones: Application to polymer-bound sulfoximines and to the synthesis of chiral sulfones
Hachtel, Jochen,Gais, Hans-Joachim
, p. 1457 - 1465 (2000)
Reaction of N-alkyl, N-aryl, and N-H sulfoximines with m- chloroperbenzoic acid cleanly gives the corresponding sulfones in high yield. In the case of the cleavage of N-alkyl and N-arylsulfoximines, formation of the corresponding nitroso compounds as the other reaction product was proven. Starting from enantio- and diastereopure sulfoximines, a number of chiral sulfones, including the axially chiral sulfone 6 and the sulfonyl- functionalized homoallylic alcohol 8, have been prepared. Reaction of the enantiopure sulfoximine 30 with Merrifield resin gave the polymer-bound sulfoximine 32. Oxidative cleavage of 32 afforded the sulfone 16 in high yield. Deprotonation of the sulfoximine resin 32 and reaction of Li-32 with benzaldehyde and propanal furnished the β-hydroxysulfoximine resins 33a and 33b, respectively. Oxidative cleavage of 33a and 33b readily afforded the β- hydroxy sulfones 14a and 14b, respectively.
Kinetics and mechanism of oxidation of aryl methyl sulfoxides with (salen)MnIII/H2O2 catalytic system
Chellamani, Arunachalam,Sengu, Paramasivan,Alhaji, Naina Mohamed Ismail
, p. 104 - 110 (2010)
The kinetics of (salen)MnIII complexes-catalysed oxidation of aryl methyl sulfoxides with hydrogen peroxide in 80% acetonitrile-20% water solvent mixture at 25 °C has been followed spectrophotometrically. The reaction is first-order in (salen)MnIII, zero-order in hydrogen peroxide and fractional-order in sulfoxide. Also, it has been found that nitrogenous bases affect the oxidation, while free-radical inhibitor does not. However, an increase in the water content of the solvent mixture causes an increase in the rate of reaction. Stoichiometry between H2O2 and sulfoxide has been found to be 1:1 and the product analysis confirms the formation of sulfone and the regeneration of (salen)MnIII complex. These observations have been well analyzed in favor of a Michaelis-Menten type mechanism, involving a manganese(III)-hydroperoxide complex as the reactive species. Using the derived rate law, the oxidant-substrate complex formation constant, K and the oxidant-substrate complex decomposition rate constant, k2 have been evaluated. The proposed mechanism has been well supported by electronic-oxidant and electronic-substrate effect studies.
Asymmetric induction by the stereomutation of racemic methyl phenyl sulfoxide with optically active acids
Liu, Kwang-Ting,Tong, Yung-Chien,Chang, Yie-Hwa
, p. 2725 - 2728 (1980)
Direct conversion of racemic methyl phenyl sulfoxide into optically active form (maximum 6.1percent e.e.) by heating with optically active acids has been observed.
Trifluoromethyl substituted N-phosphinoyloxaziridines: Organic oxidants with enhanced reactivity
Jennings, W.Brian,O'Shea, John H.,Schweppe, Adrian
, p. 101 - 103 (2001)
New N-phosphinoyloxaziridines containing a trifluoromethyl group at the 3-position are reported. Comparative studies of the rate of oxidation of methyl phenyl sulphoxide to methyl phenyl sulphone indicate that the presence of the CF3 group greatly enhances the oxidising power of N-phosphinoyl (and N-sulphonyl) oxaziridines.
The first example of direct oxidation of sulfides to sulfones by an osmate molecular oxygen system
Choudary, Boyapati M.,Reddy, Chinta Reddy V.,Prakash, Billakanti V.,Kantam, Mannepalli L.,Sreedhar
, p. 754 - 755 (2003)
Osmate-exchanged Mg-Al layered double hydroxides catalysed the delivery of two oxygen atoms simultaneously via a 3 + 1 cycloaddition to sulfide to form sulfone directly for the first time, reminiscent of 3 + 2 cycloaddition in asymmetric dihydroxylation reactions.
Microwave-assisted Cu-catalyzed protodecarboxylation of aromatic carboxylic acids
Goossen, Lukas J.,Manjolinho, Filipe,Khan, Bilal A.,Rodriguez, Nuria
, p. 2620 - 2623 (2009)
An effective protocol has been developed that allows the smooth protodecarboxylation of diversely functionalized aromatic carboxylic acids within 5-15 min. In the presence of at most 5 mol % of an inexpensive catalyst generated in situ from copper(I) oxide and 1,10-phenanthroline, even nonactivated benzoates were converted in high yields and with great preparative ease.
