104-55-2Relevant articles and documents
Chemoselective deprotection of 1,3-oxathiolanes using Amberlyst 15 and glyoxylic acid under solvent free conditions
Chavan,Soni,Kamat
, p. 1251 - 1252 (2001)
Carbonyl compounds were regenerated from corresponding 1,3-oxathiolanes via equilibrium exchange with glyoxylic acid and Amberlyst 15 as the heterogeneous catalyst, under solvent free conditions.
Highly enantioselective control of dynamic cascade transformations by dual catalysis: Asymmetric synthesis of polysubstituted spirocyclic oxindoles
Afewerki, Samson,Ma, Guangning,Ibrahem, Ismail,Liu, Leifeng,Sun, Junliang,Crdova, Armando
, p. 1266 - 1272 (2015)
The highly enantioselective (up to >99.5:0.5 er) synthesis of polysubstituted spirocyclic oxindoles with four new contiguous stereocenters, including the spiro all-carbon quaternary center, is disclosed. It is accomplished by the highly stereoselective control of a dynamic conjugate/intramolecular allylic alkylation relay sequence based on the synergistic cooperation of metal and chiral amine catalysts in which the careful selection of organic ligand, metal complex, and chiral amine is essential. The intramolecular C-C bond-forming step occurred only when both the metal and chiral amine catalysts were present. (Chemical Equation Presented).
A convenient oxidative deprotection of tetrahydropyranyl ethers with iron (III) nitrate and clay under microwave irradiation in solvent free conditions
Heravi, Majid M.,Ajami, Dariush,Mojtahedi, Mohammad M.,Ghassemzadeh, Mitra
, p. 561 - 562 (1999)
The efficient and environmentally benign oxidative deprotection of tetrahydropyranyl ethers using montmorillonite supported iron(III) nitrate under microwave irradiation under solvent free conditions is described.
Silica gel supported chromium trioxide: An efficient reagent for oxidative cleavage of oximes to carbonyl compounds under mild condition
Bendale, Pravin M.,Khadilkar, Bhushan M.
, p. 665 - 669 (2000)
A facile, efficient oxidative deblocking of aldoximes and ketoximes to their corresponding aldehydes and ketones have been achieved by using silica gel supported chromium trioxide.
Preparation and characterization of laccases immobilized on magnetic nanoparticles and their application as a recyclable nanobiocatalyst for the aerobic oxidation of alcohols in the presence of TEMPO
Rouhani, Shamila,Rostami, Amin,Salimi, Abdollah
, p. 26709 - 26718 (2016)
Laccase from Trametes versicolor was immobilized on a modified magnetic nanoparticle (MNP-Laccase) through a covalent attachment method. The morphology, structure, magnetic property and chemical composition of the immobilized laccase (MNP-Laccase) were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), alternating gradient force magnetometry (AGFM), energy-dispersive X-ray spectroscopy (EDX) and thermogravimetric analysis (TGA) techniques. The MNPs-Laccase retained the activity and exhibited higher resistance to pH and temperature changes. We have used MNPs-Laccase as a magnetically recoverable nanobiocatalyst for the mild, environmentally friendly and selective aerobic oxidation of benzylic and allylic alcohols to corresponding aldehydes in the presence of TEMPO as a redox mediator at room temperature. The magnetic nanobiocatalyst was easily and rapidly recovered by applying an external magnet device and reused up to 6 reaction runs without considerable loss of reactivity.
Catalytic oxidation of aromatic oxygenates by the heterogeneous catalyst Co-ZIF-9
Zakzeski, Joseph,Dbczak, Agnieszka,Bruijnincx, Pieter C.A.,Weckhuysen, Bert M.
, p. 79 - 85 (2011)
The catalytic activity of Co-ZIF-9, a zeolitic imidazolate framework of sodalite topology, in the oxidation of small aromatic molecules including phthalan, vanillyl alcohol, guaiacol, syringol, veratryl alcohol, and cinnamyl alcohol by molecular oxygen has been investigated. Co-ZIF-9 selectively oxidized the substrates and thus represents a promising heterogeneous catalyst for the oxidation of small aromatic substrates. Phthalan was converted to three different products, i.e. phthalide, phthalaldehyde, and small amounts of phthalic acid. In addition to phthalan, the alcohol functionality of vanillyl alcohol, veratryl alcohol, and cinnamyl alcohol was also similarly oxidized to yield the corresponding aldehydes in high yields and excellent selectivity. The effect of solvent, temperature and NaOH addition on the Co-ZIF-9 catalytic system has been studied. The presence of NaOH in the solution greatly enhanced the oxidation activity. The structure and stability of the heterogeneous catalyst was probed by UV-vis diffuse reflection spectroscopy, confirming the coordination geometry of cobalt in the catalyst framework, thermal gravimetric analysis, establishing the thermal stability of the structure, and XRD to monitor crystallinity of the catalyst. The heterogeneous nature of the catalyst was established by a hot filtration experiment, ICP analysis of the liquid phase, and by UV-vis absorption spectroscopy on the hot filtered reaction mixture.
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Lalancette et al.
, p. 3058 (1972)
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Controllable Encapsulation of "clean" Metal Clusters within MOFs through Kinetic Modulation: Towards Advanced Heterogeneous Nanocatalysts
Liu, Hongli,Chang, Lina,Bai, Cuihua,Chen, Liyu,Luque, Rafael,Li, Yingwei
, p. 5019 - 5023 (2016)
Surfactant-free tiny Pt clusters were successfully encapsulated within MOFs with controllable size and spatial distribution by a novel kinetically modulated one-step strategy. Our synthesis relies on the rational manipulation of the reduction rate of Pt i
Synthesis, characterization, and catalytic activity of a water soluble copper(II) and nickel(II) heterobimetallic complex [CuNi(μ-OH)(μ-OH2)(μ-OAc)(bpy)2](ClO4)2 in aqueous medium in the absence of a base and co-catalyst
Lal, Ram A.,Kumar, Arvind,Syiemlieh, Ibanphylla,Kurbah, Sunshine D.
, p. 2722 - 2735 (2017)
A copper(II)–nickel(II)-based catalyst system has been synthesized and characterized by elemental analysis, molar conductance, mass spectra, magnetic moment, EPR, UV-Vis, IR spectroscopy, and cyclic voltammetry. The structure of the complex was established by X-ray crystallography. The complex is an efficient catalyst, which oxidizes primary and secondary alcohols to the corresponding aldehydes and ketones at 70?°C employing 15% H2O2 as the oxidant in the absence of a base and co-catalyst.
Synthetic scope of Ru(OH)x/Al2O3-catalyzed hydrogen-transfer reactions: An application to reduction of allylic alcohols by a sequential process of isomerization/meerwein-ponndorf-verley-iype reduction
Kim, Jung Won,Koike, Takeshi,Kotani, Miyuki,Yamaguchi, Kazuya,Mizuno, Noritaka
, p. 4104 - 4109 (2008)
Reduction of allylic alcohols can be promoted efficiently by the supported ruthenium catalyst Ru(OH)x/Al2O3. Various allylic alcohols were converted to saturated alcohols in excellent yields by using 2-propanol without any additives. This Ru(OHx/Al 2O3-catalyzed reduction of a dienol proceeds only at the allylic double bond to afford the corresponding enol, and chemoselective isomerization and reduction can be realized under similar conditions. The catalysis is truly heterogeneous and the high catalytic performance can be maintained during at least three recycles of the Ru(OH)x/Al 2O3 catalyst. The transformation of allylic alcohols to saturated alcohols consists of three sequential reactions: oxidation of allylic alcohols to α,β-un-saturated carbonyl compounds; reduction of α,β-unsaturated carbonyl compounds to saturated carbonyl compounds; and reduction of saturated carbonyl compounds to saturated alcohols.
Oxidation of alcohols to carbonyl compounds with a new potassium permanganate adsorbed on Kieselguhr reagent
Lou, Ji-Dong,Lou, Wen-Xing
, p. 3697 - 3699 (1997)
A new reagent, potassium permanganate adsorbed on kieselguhr, suitable for the oxidation of alcohols to the corresponding carbonyl compounds is described.
Highly efficient, organocatalytic aerobic alcohol oxidation
Shibuya, Masatoshi,Osada, Yuji,Sasano, Yusuke,Tomizawa, Masaki,Iwabuchi, Yoshiharu
, p. 6497 - 6500 (2011)
5-Fluoro-2-azaadamantane N-oxyl (5-F-AZADO) realizes a simple, organocatalytic aerobic alcohol oxidation system that has a wide scope under mild conditions at ambient pressure and temperature and is weakly acidic and halogen- and transition-metal-free. The oxoammonium nitrate (5-F-AZADO +NO3-) works as a bifunctional catalyst of 5-F-AZADO and NOx that enables the catalytic aerobic oxidation of alcohols by itself (a metal-salt-free system).
Unveiling of a Trinuclear Cyclic Peroxidovanadate: A Potential Oxidant in Vanadium-Catalyzed Reactions
Krivosudsky, Luká?,Schwendt, Peter,Gyepes, Róbert
, p. 6306 - 6311 (2015)
The first peroxidovanadium trimer was prepared in the form of its tetrabutylammonium salt, (NBu4)3[V3O3(O2)6]·2H2O. Its X-ray structure analysis revealed a unique cyclic structur
Development of manganese(VI) oxidising agents soluble in organic solvents
Ellis, Rhys,Lee, Kee-Han,Ainsworth, Matthew,Kerr, Alexander,Viseux, Eddy M. E.
, p. 1371 - 1373 (2012)
Two manganate(VI) reagents have been prepared from permanganate salts that show excellent oxidising properties in common organic solvents. Georg Thieme Verlag Stuttgart · New York.
Barium dichromate [BaCr2O7], a mild reagent for oxidation of alcohols to their corresponding carbonyls in non-aqueous polar aprotic media
Mottaghinejad, Enayatollah,Shaafi,Ghasemzadeh
, p. 8823 - 8824 (2004)
Barium dichromate is used as a mild oxidizing agent for the selective conversion of primary and secondary alcohols to their corresponding aldehydes and ketones, respectively. Over-oxidation does not occur and primary alcohols undergo oxidation to the aldehyde. Primary and secondary benzylic alcohols are oxidized faster and more efficiently. Barium dichromate is used as a mild oxidizing agent for the selective conversion of primary and secondary alcohols to their corresponding aldehydes and ketones, respectively. Over-oxidation does not occur and primary alcohols undergo oxidation to the aldehyde. Primary and secondary benzylic alcohols are oxidized faster and more efficiently.
Selective aerobic oxidation of alcohols by using manganese oxide nanoparticles as an efficient heterogeneous catalyst
Sun, Hua-Yin,Hua, Qing,Guo, Feng-Feng,Wang, Zhi-Yong,Huang, Wei-Xin
, p. 569 - 573 (2012)
Manganese oxide (Mn3O4) nanoparticles have been successfully innovated to be efficient catalysts not only for the aerobic oxidation of various alcohols to aldehydes or ketones, but also for the selective aerobic oxidation of mixed alcohols. Copyright
Immobilized magnetic nano catalyst for oxidation of alcohol
Bhat, Pooja B.,Rajarao, Ravindra,Sahajwalla, Veena,Bhat, Badekai Ramachandra
, p. 42 - 49 (2015)
Covalent attachment of Schiff base on magnetic nanoparticles yielded good selectivity for oxidation of alcohols. The ferromagnetic interaction in the complex added comprehensive advantage in enhancing the catalytic activity of the nanocatalyst. A greener approach for alcohol oxidation was achieved in solventless method with good yield (>78%). Leaching experiments confirmed a strong interaction between magnetic support and complex. The catalyst showed significant conversion even after 5 catalytic runs.
Effective oxidation of alcohols under heterogeneous conditions with a new reagent: Manganese dioxide supported on graphite
Lou, Ji-Dong,Lu, Xiu Lian,Huang, Li-Hong,Wang, Qiang,Zou, Xiao-Nan
, p. 1342 - 1345 (2011)
A new reagent, manganese dioxide supported on graphite, under heterogeneous conditions at reflux is described for the oxidation of benzylic and allylic alcohols into the corresponding aldehydes and ketones, respectively. The main advantage of the present oxidation is that the insoluble solid support, graphite, provides a particular reaction environment capable of enhancing the reaction selectivity and reactivity. Moreover, it turns out to be very profitable in the workup, which becomes reduced to a mere filtration. The mechanism for this oxidation is also discussed. Copyright Taylor & Francis Group, LLC.
Highly Enantioselective Synthesis of Alkylpyridine Derivatives through a Michael/Michael/Aldol Cascade Reaction
Meazza, Marta,Potter, Michael,Pitak, Mateusz B.,Coles, Simon J.,Mazzanti, Andrea,Rios, Ramon
, p. 719 - 725 (2017)
A method for the synthesis of pyridine derivatives based on a triple cascade reaction catalyzed by chiral secondary amines was developed. The resulting cyclohexenes (three C–C bonds were formed) were obtained in good yields with good diastereoselectivities and excellent enantioselectivities.
From surface-inspired oxovanadium silsesquioxane models to active catalysts for the oxidation of alcohols with O2-The cinnamic acid/ metavanadate system
Ohde, Christian,Limberg, Christian
, p. 6892 - 6899 (2010)
Silsesquioxane dioxovanadate(V) complexes were investigated with respect to their potential as a catalyst for the oxidative dehydrogenation of alcohols with O2 as an oxidant. The turnover frequencies determined were comparatively low, but during the oxidation of cinnamic alcohol an increase in activity was observed in the course of the process, which was inspected more closely. It turned out that during the oxidation of cinnamic alcohol, not only was the aldehyde formed but also cinnamic acid, which in turn reacts with the silsesquioxane complex employed to give NBu4- [O2V(O 2CC2H2Ph)2], which can also be obtained from NBu4VO3 and cinnamic acid and represents a far more active catalyst, not only for cinnamic alcohol but also for other activated alcohols and hydrocarbons. The rate-determining step of the conversion corresponds to an hydrogen-atom abstraction from the C-H units, as shown by the determination of the kinetic isotope effect in case of 9-hydroxyfluorene, and the reoxidation of the reduced catalyst proceeds via a peroxo intermediate, which is also capable of oxidizing one alcohol equivalent. Furthermore the influence of the organic residues at the carboxylate ligands on the catalyst performance was investigated, which showed that the activity increases with decreasing pKs value. Moreover, it was found that during the oxidation the catalyst slowly decomposes, but can be regenerated by addition of excessive carboxylic acid.
Palladium-Catalyzed Allylic C-H Oxidative Annulation for Assembly of Functionalized 2-Substituted Quinoline Derivatives
Li, Chunsheng,Li, Jianxiao,An, Yanni,Peng, Jianwen,Wu, Wanqing,Jiang, Huanfeng
, p. 12189 - 12196 (2016)
An efficient and practical palladium-catalyzed aerobic oxidative approach to afford functionalized 2-substituted quinolines in moderate to good yields from readily available allylbenzenes with aniline is developed. The present annulation process has high functional-group tolerance and high atom economy, making it a valuable and practical method in synthetic and medicinal chemistry. Moreover, this transformation is supposed to proceed through oxidation of allylic C-H functionalization to form C-C and C-N bonds in one pot.
Direct synthesis of Fe(III) immobilized Zr-based metal–organic framework for aerobic oxidation reaction
Shu, Xin,Yu, Ying,Jiang, Yi,Luan, Yi,Ramella, Daniele
, (2017)
A Zr-based metal–organic framework with bipyridine units (UiO-67) has been utilized for the immobilization of catalytically active iron species via a post-synthetic metalation method. UiO-67 bipyridine MOF was synthesized through a simple solvothermal method and was shown to have a UiO-type structure. Post-synthetic metalation of UiO-67 MOF was performed for the immobilization of the catalytically active FeCl3. FT-IR and EDX element map suggested that FeCl3 is coordinately bonded to the UiO-67 bipyridine framework. The synthesized UiO-67-FeCl3 catalyst was used for the aerobic oxidation of alcohols and benzylic compounds in the presence of molecular oxygen. In addition, the UiO-67-FeCl3 catalyst can be reused as a solid heterogeneous catalyst without compromising its activity and selectivity.
The Aldol Reaction under High-Intensity Ultrasound: A Novel Approach to an Old Reaction
Cravotto, Giancarlo,Demetri, Alberto,Nano, Gian Mario,Palmisano, Giovanni,Penoni, Andrea,Tagliapietra, Silvia
, p. 4438 - 4444 (2003)
We have employed high-intensity ultrasound (HIU) to reinvestigate the aldol reaction (AR) in water. A number of aldols that under usual conditions would undergo elimination were isolated in acceptable to good yields. Within 15-30 min, acetophenone reacted with non-enolizable aldehydes to afford the aldol exclusively, while under conventional conditions (stirring or heating under reflux) the same compounds either failed to react or gave, after several hours, the enone, often in complex product mixtures. A library of polyols was obtained starting from a series of acetophenones and excess formaldehyde. Benzaldehyde reacted with a series of 1,3-dicarbonyl compounds to afford the corresponding bis(benzylidene) adducts. The results proved to be highly reproducible because the relevant sonochemical parameters were rigorously controlled. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
Organische Synthesen mit Uebergangsmetall-Komplexen. LXV. Aldehyde durch Hydrolyse der M=C-Bindung von Alkoxycarben-Chromkomplexen mit Wasser / Urotropin. Ein zweikerniger verbrueckter (β-Amino)vinylcarben-Chromkomplex durch Fragmentierung von Urotropin
Aumann, Rudolf,Hinterding, Peter,Krueger, Carl,Goddard, Richard
, p. 145 - 150 (1993)
The Cr=C bonds of aryl- and alkenyl(ethoxy)carbene chromium complexes 1a-d are hydrolysed under mild reaction conditions with high chemoselectivity in presence of hexamethylenetetramine (urotropine), 2, to give aldehydes 4a-d and (urotropine)Cr(CO)5, 3.The alkynyl(ethoxy)carbene chromium complex 1e reacts with urotropine in a completely different fashion and forms a binuclear (β-amino)vinylcarbene complex, 5, by fragmentation of the urotropine skeleton.
Shaken not stirred; Oxidation of alcohols with sodium dichromate
Lou, Ji-Dong,Gao, Chun-Ling,Ma, Yi-Chun,Huang, Li-Hong,Li, Li
, p. 311 - 313 (2006)
Efficient and selective oxidation of primary alcohols to the corresponding aldehydes with sodium dichromate at room temperature under solvent-free conditions by shaking is described. This new procedure can also successfully oxidise secondary alcohols.
An efficient Pd@Pro-GO heterogeneous catalyst for the α, β-dehydrogenation of saturated aldehyde and ketones
Pan, Gao-Fei,Wang, Zhe,Chang, Yi-Yuan,Hao, Yue,Wang, Yi-Chen,Xing, Rui-Guang
supporting information, (2021/12/30)
An Efficient Pd@Pro-GO heterogeneous catalyst was developed that can promote the α, β-dehydrogenation of saturated aldehyde and ketones in the yield of 73% ? 92% at mild conditions without extra oxidants and additives. Pd@Pro-GO heterogeneous catalyst was synthesized via two steps: firstly, the Pro-GO was obtained by the esterification reaction between graphene oxide (GO) and N-(tert-Butoxycarbonyl)-L-proline (Boc-Pro-OH), followed by removing the protection group tert-Butoxycarbonyl (Boc), which endowed the proline-functionalized GO with both the lewis acid site (COOH) and the bronsted base site (NH), besides, the pyrrolidine of proline also can form imine with aldehydes to activate these substrates; Second, palladium was dispersed on the proline-functionalized GO (Pro-GO) to obtained heterogeneous catalyst Pd@Pro-GO. Mechanistic studies have shown that the Pd@Pro-GO-catalyzed α,β-dehydrogenation of saturated aldehyde and ketones was realized by an improved heterogeneously catalyzed Saegusa oxidation reaction. Based on the obove characteristics, the Pd@Pro-GO will be widely used in the transition metal catalytic field.
Markovnikov Wacker-Tsuji Oxidation of Allyl(hetero)arenes and Application in a One-Pot Photo-Metal-Biocatalytic Approach to Enantioenriched Amines and Alcohols
Albarrán-Velo, Jesús,Gotor-Fernández, Vicente,Lavandera, Iván
, p. 4096 - 4108 (2021/08/19)
The Wacker-Tsuji aerobic oxidation of various allyl(hetero)arenes under photocatalytic conditions to form the corresponding methyl ketones is presented. By using a palladium complex [PdCl2(MeCN)2] and the photosensitizer [Acr-Mes]ClO4 in aqueous medium and at room temperature, and by simple irradiation with blue led light, the desired carbonyl compounds were synthesized with high conversions (>80%) and excellent selectivities (>90%). The key process was the transient formation of Pd nanoparticles that can activate oxygen, thus recycling the Pd(II) species necessary in the Wacker oxidative reaction. While light irradiation was strictly mandatory, the addition of the photocatalyst improved the reaction selectivity, due to the formation of the starting allyl(hetero)arene from some of the obtained by-products, thus entering back in the Wacker-Tsuji catalytic cycle. Once optimized, the oxidation reaction was combined in a one-pot two-step sequential protocol with an enzymatic transformation. Depending on the biocatalyst employed, i. e. an amine transaminase or an alcohol dehydrogenase, the corresponding (R)- and (S)-1-arylpropan-2-amines or 1-arylpropan-2-ols, respectively, could be synthesized in most cases with high yields (>70%) and in enantiopure form. Finally, an application of this photo-metal-biocatalytic strategy has been demonstrated in order to get access in a straightforward manner to selegiline, an anti-Parkinson drug. (Figure presented.).
Nitrosoarene-Catalyzed HFIP-Assisted Transformation of Arylmethyl Halides to Aromatic Carbonyls under Aerobic Conditions
Pradhan, Suman,Sharma, Vishali,Chatterjee, Indranil
supporting information, p. 6148 - 6152 (2021/08/03)
A rare metal-free nucleophilic nitrosoarene catalysis accompanied by highly hydrogen-bond-donor (HBD) solvent, 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), organocatalytically converts arylmethyl halides to aromatic carbonyls. This protocol offers an effective means to access a diverse array of aromatic carbonyls with good chemoselectivity under mild reaction conditions. The activation of arylmethyl halides by HFIP to generate stable carbocation and autoxidation of in situ generated hydroxylamine to nitrosoarene in the presence of atmospheric O2 are the keys to success.
