50727-94-1Relevant articles and documents
Oxidovanadium(IV) complexes of 3-hydroxy-4-pyrone and 3-hydroxy-4- pyridinone ligands: A new generation of homogeneous catalysts for the epoxidation of geraniol
Pereira, Clara,Leite, Andreia,Nunes, Ana,Rebelo, Susana L. H.,Rangel, Maria,Freire, Cristina
, p. 98 - 104 (2010)
A novel generation of homogeneous catalysts for the epoxidation of geraniol, in the presence of tert-butyl hydroperoxide oxidant is reported. Oxidovanadium(IV) complexes of 3-hydroxy-4-pyrone and 3-hydroxy-4-pyridinone ligands exhibit excellent activity and selectivity towards the 2,3-epoxygeraniol product, only differing in the reaction times and turnover frequencies. The pyrone based complexes are the most efficient catalysts showing performances similar to that of the well known oxidovanadium(IV) acetylacetonate catalyst. Graphical abstract: [Figure not available: see fulltext.]
Photo-Oxidation of 2-(2-Furyl)-1,3-Dicarbonyl Compounds
Antonioletti, R.,Bonadies, F.,Pesci, S.,Scettri, A.
, p. 3947 - 3948 (1992)
A very efficient photo-sensitized oxidation of 2-(2-furyl)-1,3-dicarbonyl compounds 1 afford directly hydroperoxides 2 in stereoselective way.Compounds 2, easily isolated, can be conveniently employed in a selective epoxidation of trisubstituted allylic alcohols by a Sharpless-type procedure.
Klein,E. et al.
, p. 2025 - 2035 (1964)
Opposite Regioselectivity in the Epoxidation of Geraniol and Linalool with Molybdenum and Tungsten Peroxo Complexes
Arcoria, Antonino,Ballistreri, Francesco Paolo,Tomaselli, Gaetano Andrea,Furia, Fulvio Di,Modene, Giorgio
, p. 2374 - 2376 (1986)
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Total Synthesis of Kadcoccinic Acid A Trimethyl Ester
Gholami, Hadi,Trost, Barry M.,Zell, Daniel,Zhang, Guoting
supporting information, p. 12286 - 12293 (2021/08/20)
The first total synthesis of the trimethyl ester of kadcoccinic acid A is described. The central structural element of our synthesis is a cyclopentenone motif that allows the assembly of the natural product skeleton. A gold(I)-catalyzed cyclization of an enynyl acetate led to efficient construction of the cyclopentenone scaffold. In this step, optimization studies revealed that the stereochemistry of the enynyl acetate dictates regioisomeric cyclopentenone formation. The synthesis further highlights an efficient copper-mediated conjugate addition, merged with a gold(I)-catalyzed Conia-ene reaction to connect the two fragments, thereby forging the D-ring of the natural product. The synthetic strategy reported herein can provide a general platform to access the skeleton of other members of this family of natural products.
Vanadium-doped sodium phosphomolybdate salts as catalysts in the terpene alcohols oxidation with hydrogen peroxide
Ferreira, Sukarno Olavo,Rodrigues, Alana Alves,Vilanculo, Castelo Bandane,da Silva, Márcio José,da Silva, Rene Chagas
, p. 24072 - 24085 (2021/07/29)
In this work, we have explored the catalytic activity of Keggin-type heteropolyanions PMo12?nVnO40(3+n)?(n= 0, 1, 2, or 3) in the form of sodium salts in green oxidation routes of terpene alcohols with hydrogen peroxide. Nerol was the model molecule selected to assess the impacts of the main reaction parameters, such as temperature, catalyst load, and stoichiometry of reactants. The impacts of the presence of vanadium at different proportions (i.e., V1, V2, and V3loads/per anion) in the structure of phosphomolybdate catalysts were assessed. All the catalysts were characterized by various techniques such as powder X-ray diffraction, attenuated diffuse reflectance infrared spectroscopy, ultraviolet-visible spectroscopy, thermogravimetric analysis, isotherms of adsorption-desorption of N2measurements of surface area, scanning electronic microscopy, energy-dispersive X-ray spectroscopy, andn-butylamine potentiometric titration. Among the catalysts assessed, Na4PMo11VO40was the most active and selective toward epoxides. The efficiency of this catalyst in the epoxidation of different terpene alcohols was investigated. Special attention was dedicated to correlating the composition and properties of the vanadium-doped phosphomolybdic catalysts with their catalytic activity.
New heptacoordinate tungsten(II) complexes with α-diimine ligands in the catalytic oxidation of multifunctional olefins
Vasconcellos-Dias, Maria,Nunes, Carla D.,Félix, Vítor,Brand?o, Paula,Calhorda, Maria José
, (2021/02/26)
New tungsten(II) and molybdenum(II) heptacoordinate complexes [MX2(CO)3(LY)] (MXLy: M = W, Mo; X = Br, I; LY = C5H4NCY = N(CH2)2CH3 with Y = H (L1), Me (L2), Ph (L3)) were synthesized and characterized by spectroscopic techniques and elemental analysis. The two tungsten complexes WXL1 (X = Br, I) were also structurally characterized by single crystal X-ray diffraction. The metal coordination environment is in both a distorted capped octahedron. The complexes with L1 and L2 ligands were grafted in MCM-41, after functionalization of the ligands with a Si(OEt)3 group. The new materials were characterized by elemental analysis, N2 adsorption isotherms, 29Si MAS and 13C MAS NMR. The tungsten(II) complexes and materials were the first examples of this type reported. All complexes and materials were tested as homogeneous and heterogeneous catalysts in the oxidation of multifunctional olefins (cis-hex-3-en-1-ol, trans-hex-3-en-1-ol, geraniol, S-limonene, and 1-octene), with tert-butyl hydroperoxide (TBHP) as oxidant. The molybdenum(II) catalyst precursors are in general very active, reaching 99% conversion and 100% selectivity in the epoxidation of trans-hex-3-en-1-ol. Their performance is comparable with that of the [Mo(η3-C3H5)X(CO)2(LY)] complexes, but it increases with immobilization. On the other hand, most of the W(II) complexes display an activity similar or inferior to that of the Mo(II) analogues and it decreases after they are supported in MCM-41. DFT calculations show that tungsten complexes and iodide ligands are more easily oxidized from M(II) to M(VI) than molybdenum ones, while the energies of relevant species in the catalytic cycle are very similar for all complexes, making the theoretical rationalization of experimental catalytic data difficult.
