100-52-7Relevant articles and documents
Synthesis of zeolite@metal-organic framework core-shell particles as bifunctional catalysts
Zhu, Guanghui,Graver, Richard,Emdadi, Laleh,Liu, Baoyu,Choi, Kyu Yong,Liu, Dongxia
, p. 30673 - 30676 (2014)
A zeolite@metal-organic framework (ZSM-5@UiO-66) core-shell composite has been synthesized for the first time by solvothermal growth of UiO-66 on the surface of ZSM-5 particles. The acidity from ZSM-5 and the basicity from the amine groups in UiO-66 obtai
-
Olah,Ho
, p. 610 (1976)
-
Linear free-energy relationships in chromium(VI) oxidation of substituted benzylamines in nonaqueous media
Thirumoorthi,Bhuvaneshwari,Elango
, p. 362 - 369 (2007)
The kinetics of oxidation of 11 para- and meta-substituted benzylamines by imidazolium fluorochromate (IFC) in different organic solvent media has been investigated in the presence of p-toluenesulfonic acid (TsOH). The reaction was run under pseudo-first-
Heterogeneous Permanganate Oxidations. 5. The Preparation of Aldehydes by Oxidative Cleavage of Carbon-Carbon Double Bonds
Lee, Donald G.,Chen, Tao,Wang, Zhao
, p. 2918 - 2919 (1993)
-
Conversion of acid chlorides to aldehydes by oxidation of alkoxyaluminum intermediates with pyridinium chlorochromate or pyridinium dichromate
Cha, Jin Soon,Kim, Jong Mi,Chun, Joong Hyun,Kwon, Oh Oun,Kwon, Sang Yong,Han, Sung Wook
, p. 204 - 207 (1999)
-
-
Leffingwell,Bluhm
, p. 1151 (1969)
-
A bifunctional approach towards the mild oxidation of organic halides: 2-dimethylamino-N,N-dimethylaniline N-oxide
Chandrasekhar, Sosale,Sridhar, Malayalam
, p. 5423 - 5425 (2000)
The titled reagent incorporates an oxygen-centred nucleophile and a basic moiety - in a suitably mutual orientation - in the same molecule. It oxidises various primary benzylic bromides to the corresponding aromatic aldehydes under relatively mild conditions (MeCN/rt-50°C/6-24 h) in high yields (83-97%), and is thus a useful alternative to the Kornblum procedure. (C) 2000 Elsevier Science Ltd.
Visible-light mediated C-C bond cleavage of 1,2-diols to carbonyls by cerium-photocatalysis
Schwarz, Johanna,K?nig, Burkhard
, p. 486 - 488 (2019)
We describe a photocatalytic method for the cleavage of vicinal diols to aldehydes and ketones. The reaction is catalyzed by blue light and a cerium-catalyst and the scope includes aryl as well as alkyl substituted diols. The simple protocol which works under air and at room temperature enables the valorization of abundant diols.
Synthesis, characterisation and catalytic activities of manganese(III) complexes of pyridoxal-based ONNO donor tetradenatate ligands
Maurya, Mannar R.,Saini, Priyanka,Haldar, Chanchal,Avecilla, Fernando
, p. 710 - 720 (2012)
Reaction of MnII(CH3COO)2 with dibasic tetradentate ligands, N,N′-ethylenebis(pyridoxylideneiminato) (H 2pydx-en, I), N,N′-propylenebis(pyridoxylideneiminato) (H 2pydx-1,3-pn, II) and 1-methyl-N,N′- ethylenebis(pyridoxylideneiminato) (H2pydx-1,2-pn, III) followed by aerial oxidation in the presence of LiCl gives complexes [MnIII(pydx- en)Cl(H2O)] (1) [MnIII(pydx-1,3-pn)Cl(CH3OH)] (2) and [MnIII(pydx-1,2-pn)Cl(H2O)] (3), respectively. Crystal and molecular structures of [Mn(pydx-en)Cl(H2O)] (1) and [Mn(pydx-1,3-pn)Cl(CH3OH)] (2) confirm their octahedral geometry and the coordination of ligands through ONNO(2-) form. Reaction of manganese(II)-exchanged zeolite-Y with these ligands in refluxing methanol followed by aerial oxidation in the presence of NaCl leads to the formation of the corresponding zeolite-Y encapsulated complexes, abbreviated herein as [MnIII(pydx-en)]-Y (4), [MnIII(pydx-1,3-pn)]-Y (5) and [MnIII(pydx-1,2-pn)]-Y (6). These encapsulated complexes are used as catalysts for the oxidation, by H2O2, of methyl phenyl sulfide, styrene and benzoin efficiently. Oxidation of methyl phenyl sulfide under the optimized reaction conditions gave ca. 86% conversion with two major products methyl phenyl sulfoxide and methyl phenyl sulfone in the ca. 70% and 30% selectivity, respectively. Oxidation of styrene catalyzed by these complexes gave at least five products namely styrene oxide, benzaldehyde, benzoic acid, 1-phenylethane-1,2-diol and phenylacetaldehyde with a maximum of 76.9% conversion of styrene by 4, 76.3% by 5 and 76.0% by 6 under optimized conditions. The selectivity of the obtained products followed the order: benzaldehyde > benzoic acid > styrene oxide > phenylacetaldehyde > 1-phenylethane-1,2-diol. Similarly, ca. 93% conversion of benzoin was obtained by these catalysts, where the selectivity of the products followed the order benzil > benzoic acid > benzaldehyde-dimethylacetal. Tests for the recyclability and heterogeneity of the reactions have also been carried. Neat complexes are equally active. However, the recycle ability of encapsulated complexes makes them better over neat ones.
Utilizing Benign Oxidants for Selective Aerobic Oxidations Using Heterogenized Platinum Nanoparticle Catalysts
Hinde, Christopher S.,Gill, Arran M.,Wells, Peter P.,Hor, T. S. Andy,Raja, Robert
, p. 1226 - 1230 (2015)
By using platinum nanoparticle catalysts that are generated in situ by extrusion from a porous copper chlorophosphate framework, the role of oxidants in the selective oxidation of benzyl alcohol to benzaldehyde was evaluated, with a view to establishing s
Mn(III) complexes with tridentate N,N,O-ligands as catalysts for the epoxidation of alkenes
Aghmiz,Mostfa,Iksi,Rivas,Gonzalez,Diaz,El Guemmout,El Laghdach,Echarri,Masdeu-Bulto
, p. 2567 - 2577 (2013)
Mn(III) complexes with tridentate Schiff bases have been prepared and applied as catalyst precursors in epoxidation of alkenes using iodosobenzene as an oxidant providing high conversions and high selectivities when cyclohexene derivatives were studied.
Oxidation of styrene oxide via chemical and photochemical methods using TiO2-CeO2-V2O5 catalysts
Castro, Laura V.,Manríquez, Ma. Elena,Ortiz-Islas, Emma,Pliego, Andrea Sánchez,Valdez, Martín Trejo
, (2020)
This work reports the preparation of the TiO2-CeO2 (TiCe) catalytic support of V2O5 catalysts, which was tested in the oxidation process of styrene oxide via chemical and photochemical methods. The TiCe-V2O5 catalytic support was prepared by the co-precipitated method from the individual metal oxides, varying the amount of vanadium oxide by 3, 6, and 10 % mol with respect to the support. The obtained catalysts were characterized by different spectroscopies, as well as by the N2 adsorption-desorption technique. The catalytic reaction test was carried out in the liquid phase during 120 min with/without ultraviolet light irradiation at 50 °C. There was no V2O5 effect on the surface area, pore volume, and pore diameter since all catalysts had similar textural values. In all samples the structures identified by X-ray diffraction were the Anatase phase and CeO2 in the cubic phase. XPS results revealed the formation of surface carbonate species, which were also identified by infrared spectroscopy. The conversion rate was better when employing ultraviolet light, and the rate increased as the V2O5 amount rose. The main reaction products were 2-phenylethanol and 1-phenylethanol. However, a low amount of benzaldehyde was detected. The selectivity to the desirable product (2-phenylethanol) increased when the reaction was irradiated with UV light and the catalyst contained a higher amount of vanadium. It was observed that the effect of UV radiation on the electric mobility produces an acceleration of the reaction to 2-phenylethanol, avoiding the 1-phenylethanol formation. The bandgap value decreased as the vanadium oxide amount increased, boosting the electric mobility.
Direct synthesis of carbonyl compounds from THP ethers with IBX in the presence of β-cyclodextrin in water
Narender,Reddy, M. Somi,Kumar, V. Pavan,Nageswar,Rao, K. Rama
, p. 1971 - 1973 (2005)
Water, an environmentally friendly reaction medium, has been utilized for the oxidative deprotection of tetrahydropyranyl ethers 1 with IBX at room temperature in the presence of β-cyclodextrin to give the corresponding carbonyl compounds 2.
RHODIUM(II) ACETATE: AN EFFECTIVE HOMOGENEOUS CATALYST FOR SELECTIVE ALLYLIC OXIDATION AND CARBON-CARBON BOND FISSION OF OLEFINS
Uemura, Sakae,Patil, Suresh R.
, p. 1743 - 1746 (1982)
Treatment of some cyclic olefins and allylbenzene with Rh2(OAc)4 in acetic acid in the presence of t-BuOOH gave the corresponding enones and allylic acetates, the former being predominant, Application to several styrene derivatives resulted in a selective C=C bond fission to give benzaldehyde or acetophenone.It is suggested that the reaction proceeds catalytically with Rh(II) acetate via an ionic pathway.
Disulfide-Catalyzed Visible-Light-Mediated Oxidative Cleavage of C=C Bonds and Evidence of an Olefin–Disulfide Charge-Transfer Complex
Deng, Yuchao,Wei, Xiao-Jing,Wang, Hui,Sun, Yuhan,No?l, Timothy,Wang, Xiao
, p. 832 - 836 (2017)
A photocatalytic method for the aerobic oxidative cleavage of C=C bonds has been developed. Electron-rich aromatic disulfides were employed as photocatalyst. Upon visible-light irradiation, typical mono- and multi-substituted aromatic olefins could be converted into ketones and aldehydes at ambient temperature. Experimental and computational studies suggest that a disulfide–olefin charge-transfer complex is possibly responsible for the unconventional dissociation of S?S bond under visible light.
Nitrogen kinetic isotope effects for the monoamine oxidase B-catalyzed oxidation of benzylamine and (1,1-2H2)benzylamine: Nitrogen rehybridization and CH bond cleavage are not concerted
MacMillar, Susanna,Edmondson, Dale E.,Matsson, Olle
, p. 12319 - 12321 (2011)
Nitrogen kinetic isotope effects for the oxidation of benzylamine and (1,1-2H2)benzylamine by recombinant human monoamine oxidase B show that cleavage of the CH bond is not concerted with rehybridization of the nitrogen atom.
Copper-Functionalized Metal–Organic Framework as Catalyst for Oxidant-Controlled Partial Oxidation of Cyclohexene
Chotmongkolsap, Pannapat,Bunchuay, Thanthapatra,Klysubun, Wantana,Tantirungrotechai, Jonggol
, p. 703 - 712 (2018)
Microwave irradiation is exploited for the facile, one-step functionalization of Cu(acac)2 to –NH2 pendant groups of MIL-53(Al)-NH2, a metal–organic framework material, under mild reaction conditions and a short reaction time. PXRD, XPS, XAS, and EPR spectroscopy are used to investigate the structure and chemical nature of the copper species on the framework. The copper center exists in the +2 oxidation state with a square-planar geometry and NO3 coordination environment. The copper complex is anchored to the framework by imine bond formation. This copper-functionalized MIL-53(Al)-NH2 or MIL-53[Cu] is employed in the catalytic oxidation of olefins using molecular oxygen (O2) or tert-butyl hydroperoxide (TBHP) as the oxidant. The chemoselectivities of the oxidation products depend on the type of oxidant and substrate. When O2 is used as the oxidant and isobutyraldehyde as the co-oxidant in the oxidation of cyclohexene with MIL-53[Cu], cyclohexene oxide is the major product. However, when TBHP is employed as the oxidant, 2-cyclohexen-1-one is the major product. Furthermore, the catalyst can be reused at least three times without a significant loss in activity.
Photochemical Electron-Transfer Reactions between Sulfides and Tetranitromethane. Oxidation vs Fragmentation of the Sulfide Radical-Cation Intermediate
Adam, Waldemar,Argueello, Juan E.,Penenory, Alicia B.
, p. 3905 - 3910 (1998)
Oxidation and/or fragmentation products are observed in the photochemical reaction of the alkyl phenyl sulfides 1a-d with tetranitromethane (TNM). The product distribution depends markedly on the substrate structure. Thus, methyl phenyl sulfide (1a) and benzyl phenyl sulfide (1b) give only the corresponding sulfoxides (oxidation). However, when the radical cation 1b?+ is generated by chemical oxidation with triarylaminium salts (Ar3N?+) in acetonitrile, in addition to oxidation fragmentation is also observed, and with an excess of Ar3N?+ oxidation is facilitated and no fragmentation is produced. For the photoreaction of diphenylmethyl phenyl sulfide (1c) with TNM, fragmentation is the main reaction, while for triphenylmethyl phenyl sulfide (1d) only this process is observed. The ease of C-S bond scission in these sulfur-centered radical cations 1.+ follows the ease of alkyl cation formation, i.e., Ph3C > Ph2CH > PhCH2 > CH3.
Selective activation of C-H bonds on the ring of ethylbenzene catalyzed by several diperoxovanadate complexes
Liu, Qiuyuan,Zhu, Liangfang,Li, Li,Guo, Bin,Hu, Xiaoke,Hu, Changwei
, p. 71 - 77 (2010)
The competitive oxidation of the C-H bonds on the aromatic ring and side-chain of ethylbenzene (EB) with hydrogen peroxide is investigated over four diperoxovanadate catalysts, that is, K3[VO(O2) 2(ox)] (bpV(ox)), K2
Double-helical ruthenium complexes of 2,2′:6′,2″,2?:6?,2″″-quinquepyridine (qpy) for multi-electron oxidation reactions
Ho, Paul Kwok-Keung,Cheung, Kung-Kai,Che, Chi-Ming
, p. 1197 - 1198 (1996)
Double-helical ruthenium complexes of 2,′:6′,2″:6″,2?:6?,2″″- quinquepyridine (qpy) are prepared from RuCl3·xH2O and qpy and the crystal structure of [Ru2(qPy)2(C2O4)][CF 3SOsub
Synergistic catalysis within TEMPO-functionalized periodic mesoporous organosilica with bridge imidazolium groups in the aerobic oxidation of alcohols
Karimi, Babak,Vahdati, Saleh,Vali, Hojatollah
, p. 63717 - 63723 (2016)
Anchoring 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) within the nanospaces of a periodic mesoporous organosilica with bridged imidazolium groups led to an unprecedented powerful bifunctional catalyst (TEMPO@PMO-IL-Br), which showed enhanced activity in the metal-free aerobic oxidation of alcohols. The catalyst and its precursors were characterized by N2 adsorption-desorption analysis, transmission electron microscopy (TEM), small angle X-ray scattering (SAXS), thermal gravimetric analysis (TGA), diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), solid state electron paramagnetic resonance (EPR) spectroscopy, elemental analysis, transmission electron microscopy (TEM) and high resolution TEM. It was clearly found that the catalytic activity of SBA-15-functionalized TEMPO (TEMPO@SBA-15) not bearing IL, TEMPO@PMO-IL-Cl, PMO-IL-AMP, or individual catalytic functionalities (PMO-IL/TEMPO@SBA-15) was inferior as compared with those obtained from TEMPO@PMO-IL-Br in the metal-free aerobic oxidation of benzyl alcohol, suggesting the critical role of co-supported TEMPO and imidazolium bromide in obtaining high catalytic activity in the described catalyst system. Our observation clearly points to the fact that the combination of imidazolium bromide units in close proximity to TEMPO moieties in the nanospaces of TEMPO@PMO-IL-Br might be indeed one of the key factors explaining the enhanced catalytic activity observed for this catalyst in the oxidation of benzyl alcohol, possibly through a synergistic catalysis relay pathway. A proposed model was suggested for the observed synergistic effect.
Facile cleavage reactions of styrylic olefins using electrochemical methods
Maki, Shojiro,Niwa, Haruki,Hirano, Takashi
, p. 1385 - 1386 (1997)
Negative constant current electrolysis of styrylic olefins in an aqueous solvent resulted in the oxidative cleavage of the double bonds, giving carbonyl compounds in good yields. The double bond conjugated with more than one aromatic ring was selectively cleaved.
Triplet State and Photodecarboxylation of Phenylglyoxylic Acid in the Presence of Water
Kuhn, Hans Jochen,Goerner, Helmut
, p. 6208 - 6219 (1988)
The photodecarboxylation of phenylglyoxylic acid (PA) was studied by quantum yield (Φd) and time-resolved conductivity measurements in polar solvents at room temperature. Φd is substantial (>/=0.3) in the presence of 3-30 M water in acetonitrile and at pH a = 1.1 in neat water.The triplet states of PA, of its ethyl ester, and of 4-carboxybenzaldehyde were observed by nanosecond laser flash photolysis and emission spectroscopy.The initial transient obtained from PA (e.g., in acetonitrile λmax = 322 nm; lifetime >/= 3 μs) is assigned to the n,?* triplet state, and a second transient (in 2-propanol; λmax = 313 nm; t1/2 > 100 μs) is assigned to the Ph-COH-COOH radical.Phosphorescence was observed in glassy matrices at -196 deg C and in acetonitrile, acetone, and acetic acid at 25 deg C.In the latter ("inert") solvents the phosphorescence intensity and the triplet lifetime (up to 20 μs) are reduced by addition of alcohols or water.The rate constant of H-atom abstraction by triplet PA from 2-propanol is 1.5 * 106 M-1 s-1 in acetonitrile.Addition of water to PA in the "inert" solvents results in a non-Stern-Volmer behavior for triplet quenching.Excitation of PA in neat aqueous solution yields the triplet of benzaldehyde, the excited photoproduct, as main transient whereas triplet PA could not be detected.A mechanism accounting for the dependences of Φd on the pH and on the H2O concentration in mixtures with acetonitrile is proposed.Water governs the photochemistry of PA in three respects, via the acid-base equilibrium, as triplet quencher, and by reducing the quantum yield of intersystem crossing to the anion triplet.
A green and efficient oxidation of benzylic alcohols using H2O2 catalyzed by Montmorillonite-K10 supported MnCl2
Najafi, Gholam Reza
, p. 1162 - 1164 (2010)
Primary and secondary benzylic alcohols were oxidized to the corresponding carbonyl compounds in good to high yields by environmentally friendly and green oxidant, H2O2 catalyzed by Montmorillonite-K10 supported manganese(II) chlorid
Synthesis, structural characterization, and catalytic reactivity of a new molybdenum(VI) complex containing 1,3,4-thiadiazole derivative as a tridentate NNO donor ligand
Moradi-Shoeili, Zeinab,Zare, Maryam,Bagherzadeh, Mojtaba,Kubicki, MacIej,Boghaei, Davar M.
, p. 548 - 559 (2015)
A new cis-dioxo molybdenum(VI) complex was obtained by reaction of 2,4-dihydroxybenzylidene(5-N,N-methylphenylamino-1,3,4-thiadiazol-2-yl)hydrazone as ligand and [MoO2(acac)2] in methanol and was characterized by elemental analyses,
Functionalized-1,3,4-oxadiazole ligands for the ruthenium-catalyzed Lemieux-Johnson type oxidation of olefins and alkynes in water
Hkiri, Shaima,Touil, Soufiane,Samarat, Ali,Sémeril, David
, (2021/11/30)
Three arene-ruthenium(II) complexes bearing alkyloxy(5-phenyl-1,3,4-oxadiazol-2-ylamino)(4-trifluoromethylphenyl)methyl ligands were quantitatively obtained through the reaction of (E)-1-(4-trifluoromethylphenyl)-N-(5-phenyl-1,3,4-oxadiazol-2-yl)-methanimine with the ruthenium precursor [RuCl2(η6-p-cymene)]2 in a mixture of the corresponding alcohol and CH2Cl2 at 50 °C. The obtained complexes were fully characterized by elemental analysis, infrared, NMR and mass spectrometry. Solid-state structures confirmed the coordination of the 1,3,4-oxadiazole moiety to the ruthenium center via their electronically enriched nitrogen atom at position 3 in the aromatic ring. These complexes were evaluated as precatalysts in the Lemieux-Johnson type oxidative cleavage of olefins and alkynes in water at room temperature with NaIO4 as oxidizing agent. Good to full conversions of olefins into the corresponding aldehydes were measured, but low catalytic activity was observed in the case of alkynes. In order to get more insight into the mechanism, three analogue arene-ruthenium complexes were synthesized and tested in the oxidative cleavage of styrene. The latter tests clearly demonstrated the importance of the hemilabile alkyloxy groups, which may form more stable (N,O)-chelate intermediates and increase the efficiency of the cis-dioxo-ruthenium(VI) catalyst.
Efficient and selective oxidation of hydrocarbons with tert-butyl hydroperoxide catalyzed by oxidovanadium(IV) unsymmetrical Schiff base complex supported on γ-Fe2O3 magnetic nanoparticles
Ardakani, Mehdi Hatefi,Sabet, Mohammad,Samani, Mahnaz
, (2022/01/22)
The catalytic activity of an oxidovanadium(IV) unsymmetrical Schiff base complex supported on γ-Fe2O3 magnetic nanoparticles, γ-Fe2O3@[VO(salenac-OH)] in which salenac-OH = [9-(2′,4′-dihydroxyphenyl)-5,8-diaza-4
Selective catalytic synthesis of bio-based high value chemical of benzoic acid from xylan with Co2MnO4@MCM-41 catalyst
Fan, Minghui,He, Yuting,Li, Quanxin,Luo, Yuehui,Yang, Mingyu,Zhang, Yanhua,Zhu, Lijuan
, (2021/12/20)
The efficient synthesis of bio-based chemicals using renewable carbon resources is of great significance to promote sustainable chemistry and develop green economy. This work aims to demonstrate that benzoic acid, an important high added value chemical in petrochemical industry, can be selectively synthesized using xylan (a typical model compound of hemicellulose). This novel controllable transformation process was achieved by selective catalytic pyrolysis of xylan and subsequent catalytic oxidation. The highest benzoic acid selectivity of 88.3 % with 90.5 % conversion was obtained using the 10wt%Co2MnO4@MCM-41 catalyst under the optimized reaction conditions (80 °C, 4 h). Based on the study of the model compounds and catalyst's characterizations, the reaction pathways for the catalytic transformation of xylan to bio-based benzoic acid were proposed.