2855-19-8Relevant articles and documents
Synthesis of poly(ethylene glycol)-supported manganese porphyrines: Efficient, recoverable and recyclable catalysts for epoxidation of alkenes
Benaglia, Maurizio,Danelli, Tamara,Pozzi, Gianluca
, p. 454 - 456 (2003)
Two new poly(ethylene glycol) supported manganese porphyrins have been prepared and their catalytic activity and recyclability were investigated for the epoxidation of alkenes using H2O2 and PhIO as stoichiometric oxidants.
A practical method for epoxidation of terminal olefins with 30% hydrogen peroxide under halide-free conditions
Sato, Kazuhiko,Aoki, Masao,Ogawa, Masami,Hashimoto, Tadashi,Noyori, Ryoji
, p. 8310 - 8311 (1996)
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Efficient epoxidation of cyclododecene and dodecene catalysed by polybenzimidazole supported Mo(VI) complex
Mbeleck, Rene,Mohammed, Misbahu Ladan,Ambroziak, Krzysztof,Sherrington, David C.,Saha, Basudeb
, p. 287 - 293 (2015)
A polybenzimidazole supported Mo(VI) complex (PBI.Mo) has been prepared and characterised. The catalytic activity of PBI.Mo for the epoxidation of cyclododecene and dodecene with tert-butyl hydroperoxide (TBHP) as an oxidant has been studied under different reaction conditions in a batch reactor. The stability of heterogeneous Mo(VI) catalyst was evaluated by recycling a sample in batch reaction using conditions that will form the basis of continuous process. The leaching of Mo species from PBI.Mo has been investigated by isolating any residue from reaction supernatant solutions following the removal of the heterogeneous catalyst, then using the residues as potential catalyst in epoxidation reactions. The batch epoxidation experimental data provided useful information for conducting continuous epoxidation in a reactive distillation column (RDC).
Investigation of physicochemical properties for novel perrhenate ionic liquid and its catalytic application towards epoxidation of olefins
Song, Zongren,Liu, Xueke,Zhang, Hao,Fang, Dawei,Ma, Xiaoxue
, (2021)
Abstract: A novel ionic liquid (IL) based on catalytic functional metal rhenium, [Smim][ReO4] (1-heptyl-3-methyl-imidazolium perrhenate) was synthesized and characterized. Density and surface tension values of the IL were determined at different temperatures, and the volume and surface properties were calculated and discussed, respectively. Furthermore, the synthesized ionic liquid [Smim][ReO4] was used as a green solvent and catalyst for homogeneous catalyzed epoxidation of olefin with urea hydrogen peroxide (UHP) oxidant. The effect of factors of catalyst, oxidant, reaction time, and reaction temperature was discussed. The conversion of cyclohexene and cyclooctene is over 99% at optimum conditions. The IL [Smim][ReO4] as catalyst and solvent are characterized by high efficiency, long service life and recoverability, which is a better green homogeneous catalyst for epoxidation of olefins. Graphic Abstract: A novel IL based on catalytic functional metal rhenium, [Smim][ReO4] was synthesized and characterized. The volume and surface properties were calculated and discussed by the density and surface tension values at different temperatures, respectively. Furthermore, the as-synthesized [Smim][ReO4] was used as a green solvent and catalyst for homogeneous catalyzed epoxidation of olefin with urea hydrogen peroxide (UHP) oxidant. The results showed that the yield and selectivity of the reaction were up to 99%, and the catalytic efficiency of [Smim][ReO4] did not decrease significantly after five times recycling. Easy separation, recycle, nontoxicity and homogeneous catalysis are the main advantages of perrhenate ionic liquids over other heterogeneous catalysts containing organic solvents.[Figure not available: see fulltext.].
A new protocol for in situ dioxirane reactions: Stoichiometric in oxone and catalytic in fluorinated acetophenones
Li, Wei,Fuchs, Philip L.
, p. 2853 - 2856 (2003)
(Matrix presented) Dioxiranes made in situ from the commercially available tetrafluoroacetophenones (7, 8) and pentafluoroacetophenone (9) are reported for highly efficient epoxidation of olefins for the first time. Studies showed that ketone 7, 8, or 9 c
Dioxo-molybdenum(VI) unsymmetrical Schiff base complex supported on CoFe2O4@SiO2 nanoparticles as a new magnetically recoverable nanocatalyst for selective epoxidation of alkenes
Ardakani, Mehdi Hatefi,Sabet, Mohammad,Samani, Mahnaz
, (2022/03/27)
In the present work, a dioxo-molybdenum unsymmetrical Schiff base complex, [MoO2(salenac-OH)], in which salenac-OH = [9-(2',4'-dihydroxyphenyl)-5,8-diaza-4-methylnona-2,4,8-trienato](-2), has been prepared and covalently immobilized on the sili
Synthesis, characterization and catalytic activities of nonheme manganese(III) complexes: Preferential formation of cis olefin oxide owing to steric hindrance
Kim, Cheal,Lee, Jiyoung,Moon, Sungjin,Park, Soyoung
, (2022/03/15)
Three mononuclear nonheme MnIII(salophen) complexes, 1a-1c, with tetradentate ligands containing two deprotonated phenolates ([(X2-tert-butyl-salophen)Mn(OAc)(H2O)] (tert-butyl-salophen = N,N′-bis(6-di-tert-butylsalicylidene)-1,2-phenylenediaminato, 1a for X = Cl, 1b for X = H, and 1c for X = CH3)) were synthesized and characterized using 1H NMR, 13C NMR, elemental analysis and ESI-Mass spectrometry. These Mn(III) complexes were used to efficiently catalyze the epoxidation reactions of diverse aliphatic, aromatic and terminal alkenes to form the corresponding epoxides with MCPBA (m-chloroperoxybenzoic acid) as an oxidant under mild conditions. Notably, catalysts 1a-1c preferably react with the cis-alkene because of the steric hindrance between the reactive intermediate MnIII-OOC(O)R and the trans-type substrate. A Hammett study and product analysis using PPAA (peroxyphenylacetic acid) as a mechanistic indicator suggested that the peracid reacted with the Mn(III) complex to generate the MnIII-OOC(O)R intermediate, which underwent both homolysis and heterolysis to form MnIV=O or MnV=O. The reactive MnV=O might participate in the alkene epoxidation with good stereospecificity, whereas the MnIV=O species might trigger radical-type oxidation to produce non-stereospecific by-products, such as ketones and aldehyde. On the other hand, MnIII-OOC(O)R (2) could oxidize the reactive cyclohexene to the epoxide, whereas it was unable to epoxidize the poorly reactive 1-octene.
