1439-07-2Relevant articles and documents
Epoxidation and hydroxylation reactions catalyzed by the manganese and iron complexes of 5,10,15,20-tetrakis(2,6-dimethoxyphenyl)porphyrin
Baciocchi, Enrico,Boschi, Tristano,Galli, Carlo,Lapi, Andrea,Tagliatesta, Pietro
, p. 4497 - 4502 (1997)
Manganese(III) and iron(III) complexes of 5,10,15,20-tetrakis-(2,6-dimethoxyphenyl)porphyrin (H2TDMeOPP) were tested as catalysts in the epoxidation of alkenes and in the hydroxylation of adamantane with H2O2 (in the prese
Cp* iridium complexes give catalytic alkane hydroxylation with retention of stereochemistry
Zhou, Meng,Schley, Nathan D.,Crabtree, Robert H.
, p. 12550 - 12551 (2010)
A series of Cp Ir complexes can catalyze C-H oxidation, with ceric ammonium nitrate as the terminal oxidant and water as the source of oxygen. Remarkably the hydroxylation of cis-decalin and 1,4-dimethylcyclohexane proceeds with retention of stereochemistry. With H2O18, cis-decalin oxidation gave 18O incorporation into the product cis-decalol.
Catalytic activity of Mn(III) and Fe(III) complexes of meso-tetra(n-propyl) porphyrin in oxidation of olefins: Meso-alkyl substituent in comparison with the alkenyl and aryl ones
Zakavi, Saeed,Talebzadeh, Sadegh,Rayati, Saeed
, p. 368 - 372 (2012)
Catalytic activity of Mn(III) and Fe(III) complexes of meso-tetra(n-propyl) porphyrin, MnT(n-Pr)P(X) and FeT(n-Pr)P(X) (X = Cl, SCN, OAc) in oxidation of olefins with tetra-n-butylammonium periodate at room temperature has been studied. The influence of different parameters including the molar ratio of catalyst to imidazole, type of counter ion (X) and oxidative stability of metalloporphyrins on the efficiency of the catalysts was investigated. The results of competitive oxidation of cis- and trans-stilbene suggest the presence of a high-valent Mn-oxo as the predominant oxidant species in equilibrium with a six coordinate complex, MnT(n-Pr)P(ImH)(IO4) in the case of MnT(n-Pr)P(OAc). An unusual preference for trans-stilbene over cis-stilbene was observed in the reaction catalyzed by FeT(n-Pr)P(OAc). Control reaction indicated a significant cis- to trans-isomerization (81%) in oxidation of cis-stilbene catalyzed by FeT(n-Pr)P(OAc) which may explain the observed unusual cis to trans-stilbene oxide ratio. While oxidation of cyclooctene and styrene led to the exclusive formation of the corresponding epoxides, oxidation of cyclohexene gave 2-cyclohexe-1-ol and cyclohexene oxide as the products. However, the results of this study clearly demonstrate the key role played by the group substituted at the meso positions of metalloporphyrins on their catalytic activity, apart from the electron-donating or electron-withdrawing properties of the substituents.
Comparative study of catalytic activity of some biomimetic models of cytochrome P450 in oxidation of olefins with tetra-n-butylammonium periodate: Electron-rich Mn-porphyrins versus the electron-deficient ones
Zakavi, Saeed,Heidarizadi, Fatemeh,Rayati, Saeed
, p. 1010 - 1013 (2011)
Oxidation of a wide range of cyclic and acyclic olefins with tetra-n-butylammonium periodate shows different orders of catalytic activity for a series of electron-rich and electron-deficient Mn-porphyrins in oxidation of various alkenes. While the Mn(III) complex of meso-tetra(4-thiomethoxyphenyl) porphyrin, MnT(4-SCH3P)P(OAc), has the highest activity among the series, the β tetra-brominted derivative shows the lowest catalytic efficiency for the oxidation of the used olefins with the exception of cis- and trans-stilbene. The results clearly show that the electron-withdrawing effects of meso- and β-substituents may increase or decrease the catalytic activity of Mn-porphyrins in the case of different olefins.
Use of titanium-containing silica catalysts prepared by rapid and straightforward method in selective oxidations
Pirovano,Guidotti,Dal Santo,Psaro,Kholdeeva,Ivanchikova
, p. 170 - 177 (2012)
A series of titanium-containing silica catalysts (Ti4/SiO 2) with small oligomeric Ti centres is obtained by impregnation of the air-stable and water-soluble tetranuclear Ti complex (NH4) 8[Ti4(C6H4O7) 4(O2)4]·8H2O onto commercial non-ordered mesoporous silica supports. Catalyst preparation is performed under very mild conditions, with no controlled atmosphere, following a simple, cheap, safe and sustainable methodology. Ti4/SiO2 catalysts can be used in the presence of TBHP or aqueous hydrogen peroxide and were tested in the selective oxidation of limonene, cyclohexene, trans-stilbene and 2,3,6-trimethylphenol. These catalysts showed performances fully comparable to (or even better than) those obtained with titanium-silicate materials prepared via conventional post-synthesis grafting approaches from organometallic precursors.
Catalytic ferrocenyl sulfides for the asymmetric transformation of aldehydes into epoxides
Miniere, Stephanie,Reboul, Vincent,Metzner, Patrick,Fochi, Mariafrancesca,Bonini, Bianca Flavia
, p. 3275 - 3280 (2004)
Six ferrocenyl sulfides, exhibiting planar and central chiralities, have been screened as a catalytic source of asymmetric sulfonium ylides. A one-pot reaction has been achieved, involving the addition of an aldehyde, benzyl bromide, 20% molar equivalent of the ferrocenyl sulfide, sodium iodide in a mixture of tert-butanol and water. The best results were observed with enantiopure sulfide 3a, bearing a tert-butyl group. Good yields of stilbene oxides were obtained, with enantiomeric excesses ranging from 74% to 94%. trans/cis-Diastereomeric ratios ranged from 60:40 to 86:14. The chiral sulfide was recovered. An unexpected case of stereoconvergence was observed with diastereoisomers 3a and 3b. A model is proposed to account for the asymmetric induction, based on a conformation locked by the tert-butyl group and the interplay of planar and remote central chiralities.
First structurally characterized optically active mononuclear Mn(IV) complex: Synthesis, crystal structure and properties of [MnIVL 2] {H2L = S-(-)-2-[(2-hydroxy-1-phenylethylimino)methyl] phenol}
Pradeep, Chullikkattil P.,Htwe, Tin,Zacharias, Panthapally S.,Das, Samar K.
, p. 735 - 739 (2004)
The reaction of Mn(CH3COO)2·4H2O with H2L {H2L = S-(-)-2-[(2-hydroxy-1-phenylethylimino) methyl]phenol} in the presence of air afforded dark brown crystals of [Mn IVL2], 1. Compo
Asymmetric epoxidation catalyzed by esters of α-hydroxy-8-oxabicyclo[3.2.1]octan-3-one
Armstrong, Alan,Moss, William O.,Reeves, Jonathan R.
, p. 2779 - 2781 (2001)
Several esters of α-hydroxy-8-oxabicyclo[3.2.1]octan-3-one were prepared and tested as catalysts for alkene epoxidation by Oxone.
Epoxidation of olefins by superoxide in the presence of acyl halide
Nagano,Arakane,Hirobe
, p. 3719 - 3721 (1980)
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A Convenient Synthesis of 1,2-Alkanediyl Carbonates
Venturello, Carlo,D'Aloisio, Rino
, p. 33 - 34 (1985)
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Preferential azido bridging regulating the structural aspects in cobalt(III) and copper(II)-Schiff base complexes: Syntheses, magnetostructural correlations and catalytic studies
Ray, Aurkie,Rosair, Georgina M.,Pilet, Guillaume,Dede, Bülent,Gómez-García, Carlos J.,Signorella, Sandra,Bellú, Sebastián,Mitra, Samiran
, p. 20 - 30 (2011)
A tridentate NNO donor Schiff base ligand [(1Z,3E)-3-((pyridin-2-yl) methylimino)-1-phenylbut-1-en-1-ol = LH] in presence of azide ions coordinates with cobalt(II) and copper(II) ions giving rise to three new coordination complexes [Co2(L)2(μ1,1-N3) 2(N3)2] (1), [Cu2(L) 2(μ1,3-N3)]·ClO4 (2) and [(μ1,1-N3)2Cu5(μ-OL) 2(μ1,1-N3)4(μ1,1,1- N3)2]n (3). The complexes have been characterized by elemental analysis, FT-IR, UV-Vis spectral studies, and single crystal X-ray diffraction studies. These complexes demonstrate that under different synthetic conditions the azide ions and the Schiff base ligand (LH) show different coordination modes with cobalt(II) and copper(II) ions, giving rise to unusual dinuclear and polynuclear species (1, 2 and 3) whose structural variations are discussed. Magneto-structural correlation for the very rare singly μ1,3-N3 bridged CuII-Schiff base dinuclear species (2) has been studied. In addition, the catalytic properties of 1 for alkene oxidation and the general catalase-like activity behavior of 2 have been discussed.
A host-guest epoxidation catalyst with enhanced activity and stability
Elemans,Bijsterveld,Rowan,Nolte
, p. 2443 - 2444 (2000)
A porphyrin-capped molecular clip epoxidises olefins, depending on the axial ligand used, with enhanced activity or stability.
A C2 symmetric chiral ketone for catalytic asymmetric epoxidation of unfunctionalized olefins
Yang, Dan,Yip, Yiu-Chung,Tang, Man-Wai,Wong, Man-Kin,Zheng, Jian-Hua,Cheung, Kung-Kai
, p. 491 - 492 (1996)
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Olefin epoxidation with bis(trimethylsilyl) peroxide catalyzed by inorganic oxorhenium derivatives. Controlled release of hydrogen peroxide
Yudin,Chiang,Adolfsson,Copéret
, p. 4713 - 4718 (2001)
The replacement of organometallic rhenium species (e.g., CH3ReO3) by less expensive and more readily available inorganic rhenium oxides (e.g., Re2O7, ReO3(OH), and ReO3) can be accomplished using bis(trimethylsilyl) peroxide (BTSP) as oxidant in place of aqueous H2O2. Using a catalytic amount of a proton source, controlled release of hydrogen peroxide helps preserve sensitive peroxorhenium species and enables catalytic turnover to take place. Systematic investigation of the oxorhenium catalyst precursors, substrate scope, and effects of various additives on olefin epoxidation with BTSP are reported in this contribution.
In the Presence of Imidazole, Iron- and Manganese-prophyrins catalyse the Epoxidation of Alkenes by Alkyl Hydroperoxides
Mansuy, Daniel,Battioni, Pierrette,Renaud, Jean-Paul
, p. 1255 - 1257 (1984)
In the presence of imidazole, Mn(TPP)(Cl) and Fe(TPP)(Cl) (TPP = tetraphenylporphyrin) catalyse the epoxidation of styrene, cyclohexene, 2-methylhept-2-ene, and stilbene by cumyl hydroperoxide; in the case of Mn(TPP)(Cl), a transient species, characterize
Epoxidation of alkenes with molecular oxygen catalyzed by a manganese porphyrin-based metal-organic framework
Brown, Jonathan W.,Nguyen, Quyen T.,Otto, Trenton,Jarenwattananon, Nanette N.,Gl?ggler, Stefan,Bouchard, Louis-S.
, p. 50 - 54 (2015)
The flexible nature of reticular assemblies and high specific surfaces ofmetalorganic frameworks (MOFs) offers new opportunities for the design of heterogeneous catalysts capable of industrially relevant reactions. We demonstrate the first instance of alkene epoxidation at mild conditions using molecular oxygen by a manganese porphyrin containing MOF, MOF-525-Mn [Zr6O4 (OH)4 (MgC48H24O8N4Cl)3]. This zirconium MOF with a manganese porphyrin catalyst shows minimal deactivation over long periods and maintains its structure and high activity aftermultiple catalytic cycles. Kinetic studies of styrene epoxidation are in agreement with theoretical and experimental studies of homogeneous reactions with the same porphyrin unit, suggesting that the heterogeneous catalyst operates according to a similar mechanism as its homogeneous counterpart.
The catalytic function of a silica gel-immobilized Mn(II)-hydrazide complex for alkene epoxidation with H2O2
Ghorbanloo, Massomeh,Monfared, Hassan Hosseini,Janiak, Christoph
, p. 12 - 20 (2011)
An efficient and highly selective heterogeneous catalyst was developed by immobilization of a manganese complex on an inorganic support to yield (silica gel)-O2(EtO)Si-L1-Mn(HL2) [(L1) - modified salicylaldiminato and H2L2(E)- N′-(2-hydroxy-3-methoxybenzylidene)benzohydrazide]. Mn(II) has been anchored on the surface of functionalized silica by means of N,O-coordination to the covalently Si-O bound modified salicylaldiminato Schiff base ligand. The prepared material (silica gel)-O2(EtO)Si-L1-Mn(HL 2), was characterized by elemental and thermogravimetric analyses (TGA and DTA), UV-vis and FT-IR spectroscopy. This new material is demonstrated to be a very active catalyst in clean epoxidation reactions using a combined oxidant of aqueous hydrogen peroxide and actonitrile in the presence of aqueous sodium hydrogencarbonate. The effects of reaction parameters such as solvent, NaHCO3 and oxidant in the epoxidation of cis-cyclooctene were investigated. Cycloalkenes were oxidized efficiently to their corresponding epoxide with 87-100% selectivity in the presence of this catalyst. This catalytic system showed also good activities in the epoxidation of linear alkenes. The obtained results show that this catalyst is a robust and stable heterogeneous catalyst which can be recovered quantitatively by simple filtration and reused multiple times without loss of its activity.
Salicylaldoxime and salen containing imidazolium ionic liquids for biphasic catalysis and metal extractions
Naik, Prashant U.,McManus, Gregory J.,Zaworotko, Michael J.,Singer, Robert D.
, p. 4834 - 4836 (2008)
Imidazolium salts containing salicylaldoxime or salen ligands readily form ionic metal complexes with copper and manganese; hence offering applications in metal extractions and biphasic catalysis.
Homochiral Metal-Organic Frameworks for Enantioselective Separations in Liquid Chromatography
Corella-Ochoa, M. Nieves,Tapia, Jesús B.,Rubin, Heather N.,Lillo, Vanesa,González-Cobos, Jesús,Nú?ez-Rico, José Luis,Balestra, Salvador R.G.,Almora-Barrios, Neyvis,Lledós, Marina,Gu?ll-Bara, Arnau,Cabezas-Giménez, Juanjo,Escudero-Adán, Eduardo C.,Vidal-Ferran, Anton,Calero, Sofiá,Reynolds, Melissa,Martí-Gastaldo, Carlos,Galán-Mascarós, José Ramón
, p. 14306 - 14316 (2019)
Selective separation of enantiomers is a substantial challenge for the pharmaceutical industry. Chromatography on chiral stationary phases is the standard method, but at a very high cost for industrial-scale purification due to the high cost of the chiral stationary phases. Typically, these materials are poorly robust, expensive to manufacture, and often too specific for a single desired substrate, lacking desirable versatility across different chiral analytes. Here, we disclose a porous, robust homochiral metal-organic framework (MOF), TAMOF-1, built from copper(II) and an affordable linker prepared from natural l-histidine. TAMOF-1 has shown to be able to separate a variety of model racemic mixtures, including drugs, in a wide range of solvents of different polarity, outperforming several commercial chiral columns for HPLC separations. Although not exploited in the present article, it is worthy to mention that the preparation of this new material is scalable to the multikilogram scale, opening unprecedented possibilities for low-energy chiral separation at the industrial scale.
Epoxidations catalyzed by manganese(v) oxo and lmido complexes: Role of the oxidant mn oxo (lmido) intermediate
Leeladee, Pannee,Goldberg, David P.
, p. 3083 - 3085 (2010)
The manganese(V) oxo complex (TBP8Cz)Mnv(O) (1) is shown to catalyze the epoxidation of alkenes with a series of iodosylarenes (ArIO) as oxidants. Competition experiments reveal that the identity of ArIO influences the product ratios, implicating an unusual coordinated oxo-metal-ArIO intermediate (1-OIAr) as the active catalytic species. The isoelectronic manganese(V) imido complex (TBP8Cz)Mnv(NMes) (2) does not participate in NR transfer but does catalyze epoxidations with ArIO as the O-atom source, suggesting a mechanism similar to that seen for 1. Direct evidence (ESIMS) is obtained for 1-OIMes.
Laser flash photolysis formation and direct kinetic studies of manganese(V)-oxo porphyrin intermediates
Zhang, Rui,Newcomb, Martin
, p. 12418 - 12419 (2003)
Irradiation of porphyrin-manganese(III) perchlorate complexes in acetonitrile with 355 nm laser light gave MnV-oxo intermediates that were characterized by their UV-vis spectra and reactivities. The MnV-oxo species of tetrakis(pentaf
Heterogenization of three homogeneous catalysts: A comparative study as epoxidation catalyst
Adhikary, Jaydeep,Guha, Averi,Chattopadhyay, Tanmay,Das, Debasis
, p. 1 - 9 (2013)
Three homogeneous catalysts, MnL1Cl·2H2O(1.2 H2O) (HmC-1), FeL1(NO3)·3H2O (HmC-2) and CoL1(NO3)-·2H2O (HmC-3) [L1 = N,N′-ethylenebis(3-formyl-5-m
Carboranycarboxylate Complexes as Efficient Catalysts in Epoxidation Reactions
Fontanet, Mònica,Rodríguez, Montserrat,Vi?as, Clara,Teixidor, Francesc,Romero, Isabel
, p. 4425 - 4429 (2017)
This work presents the first examples of carboranylcarboxylate complexes as precatalysts in epoxidation reactions with the use of peracetic acid as the oxidant. The manganese [Mn(μ-H2O)(1-CH3-2-CO2-1,2-closo-C2B10H10)2]n·(H2O)n (1), [Mn2(1-CH3-2-CO2-1,2-closo-C2B10H10)4(2,2′-bpy)2] (2, bpy = bipyridine), [Mn(1-CH3-2-CO2-1,2-closo-C2B10H10)2(bpm)]n (3, bpm = bipyrimidine), and [Mn(1-CH3-2-CO2-1,2-closo-C2B10H10)2(2,2′-bpy)2] (4) complexes and the cobalt [Co2(μ-H2O)(1-CH3-2-CO2-1,2-closo-C2B10H10)4(thf)4] (6) complex, all containing the carboranylcarboxylic 1-CH3-2-CO2H-1,2-closo-C2B10H10 (LH) ligand, together with Mn3(OAc)6(2,2′-bpy)2 (5) displayed good performance with high conversions and selectivity values in short reaction times, in most cases. This work highlights that the coordination of the carboranylcarboxylic ligand to the metal ions is crucial to the performance of the complexes as catalysts.
Efficient epoxidation of alkenes with sodium periodate catalyzed by manganese porphyrins in ionic liquid: Investigation of catalyst reusability
Tangestaninejad, Shahram,Moghadam, Majid,Mirkhani, Valiollah,Mohammadpoor-Baltork, Iraj,Hajian, Robabeh
, p. 1501 - 1503 (2010)
In the present work, efficient epoxidation of alkenes with sodium periodate catalyzed by tetraphenylporphyrinatomanganese(III) chloride, Mn(TPP)Cl, and octabromotetraphenylporphyrinatomanganese(III) chloride, Mn(Br 8TPP)Cl, using (1-n-butyl-3-m
First chiral selenium ylides used for asymmetric conversion of aldehydes into epoxides
Takada,Metzner,Philouze
, p. 2350 - 2351 (2001)
Enantioenriched selenonium ylides have been generated by addition of benzyl bromide to C2 symmetric (2R,5R)2,5-dimethylselenolane in the presence of NaOH, and subsequently reacted with a variety of aldehydes to give oxiranes with excellent enantiomeric excesses (a catalytic version has been achieved); also, an aliphatic cyclic hypervalent dibromoselenurane structure has been demonstrated by X-ray analysis.
Asymmetric Epoxidation of Unfunctionalized Olefins Using Novel Chiral Dihydroisoquinolinium Salts as Organocatalysts
Ali, K. Ben
, p. 638 - 646 (2021/06/02)
Abstract: Two new non-racemic chiral dihydroisoquinolinium salts with N-substituents bulkier than a methyl group have been synthesized from (1S,2R)-norephedrine. These salts were used to catalyze asymmetric epoxidation of a series of prochiral olefins. One of the two new catalysts provided higher enantioselectivities (up to 66% ee) than the reference salt containing an N-methyl substituent.
Nonheme manganese(III) complexes for various olefin epoxidation: Synthesis, characterization and catalytic activity
Lee, Sojeong,Park, Soyoung,Lee, Myoung Mi,Lee, Jiyoung,Kim, Cheal
, (2021/03/14)
Three mononuclear imine-based non-heme manganese(III) complexes with tetradentate ligands which have two deprotonated phenolate moieties, ([(X2saloph)Mn(OAc)(H2O)], 1a for X = Cl, 1b for X = H, and 1c for X = CH3, saloph = N,N-o-phenylenebis(salicylidenaminato)), were synthesized and characterized by 1H NMR, 13C NMR, ESI-Mass and elemental analysis. MnIII complexes catalysed efficiently various olefin epoxidation reactions with meta-chloroperbenzoic acid (MCPBA) under the mild condition. MnIII complexes 1a and 1c with the electron-withdrawing group -Cl and electron-donating group –CH3 showed little substituent effect on the epoxidation reactions. Product analysis, Hammett study and competition experiments with cis- and trans-2-octene suggested that MnIV = O, MnV = O, and MnIII-OOC(O)R species might be key oxidants in the epoxidation reaction under this catalytic system. In addition, the use of PPAA as a mechanistic probe demonstrated that Mn-acylperoxo intermediate (MnIII-OOC(O)R) 2 generated from the reaction of peracid with manganese complexes underwent both the heterolysis and the homolysis to produce MnV = O (3) or MnIV = O species (4). Moreover, the MnIII-OOC(O)R 2 species could react directly with the easy-to-oxidize substrate to give epoxide, whereas the species 2 might not be competent to the difficult-to-oxidize substrate for the epoxidation reaction.
Substituent effects in dioxovanadium(V) schiff-base complexes: Tuning the outcomes of oxidation reactions
McCaffrey, Vanessa P.,Conover, Olivia Q.,Bernard, Michael A.,Yarranton, Jonathan T.,Lessnau, Nicholas R.,Hempfling, Jordan P.
, (2021/06/21)
Dioxovanadium(V) salicylaldehyde semicarbazone complexes with substituents on the ligand that span the range of electron donating (methoxy) to electron withdrawing (nitro) have been synthesized and characterized by NMR, IR, CV and EPR. The reactivity of these complexes toward the oxidation of styrene (as compared to the proteo complex and vanadyl acetylacetonate) has been studied in the presence of two different oxidants (hydrogen peroxide and tert-butyl hydrogen peroxide, TBHP). The complexes have been shown to exhibit different selectivity towards epoxidation versus oxidative cleavage based on the substitution of the ligand and the oxidant chosen. Epoxidation is favored with the methoxy substituted complex in the presence of hydrogen peroxide, while oxidative cleavage is the preferred reaction pathway for the nitro substituted complex with hydrogen peroxide. Conversions for these reaction are comparable to similar catalysts but with improved selectivity.
