122-78-1Relevant articles and documents
Structure and Unprecedented Reactivity of a Mononuclear Nonheme Cobalt(III) Iodosylbenzene Complex
Fukuzumi, Shunichi,Kim, Kyung Ha,Lee, Yong-Min,Nam, Wonwoo,Seo, Mi Sook,Shearer, Jason,Yang, Jindou
, p. 13581 - 13585 (2020)
A mononuclear nonheme cobalt(III) iodosylbenzene complex, [CoIII(TQA)(OIPh)(OH)]2+ (1), is synthesized and characterized structurally and spectroscopically. While 1 is a sluggish oxidant in oxidation reactions, it becomes a competent oxidant in oxygen atom transfer reactions, such as olefin epoxidation, in the presence of a small amount of proton. More interestingly, 1 shows a nucleophilic reactivity in aldehyde deformylation reaction, demonstrating that 1 has an amphoteric reactivity. Another interesting observation is that 1 can be used as an oxygen atom donor in the generation of high-valent metal-oxo complexes. To our knowledge, we present the first crystal structure of a CoIII iodosylbenzene complex and the unprecedented reactivity of metal-iodosylarene adduct.
Selective isomerization of aryl substituted epoxides to aldehydes via iron Lewis acid catalysis
Picione, John,Mahmood, Syed J.,Gill, Andy,Hilliard, Marion,Hossain, M. Mahmun
, p. 2681 - 2684 (1998)
The iron Lewis acid [(η5-C5H5)Fe(CO)2(THF)]+BF4- (2) catalyzes the ring opening isomerization of aryl substituted epoxides (1) to aldehydes (3) in excellent yield.
REGIOSELECTIVITY OF OLEFIN OXIDATION BY IODOSOBENZENE CATALYZED BY METALLOPORPHYRINS: CONTROL BY THE CATALYST
Mansuy, Daniel,Leclaire, Jacques,Fontecave, Marc,Dansette, Patrick
, p. 2847 - 2857 (1984)
The regioselectivity of the oxidation of three monosubstituted olefins, 6-phenoxyhex-1-ene, hex-1-ene and styrene, by iodosobenzene in the presence of various Fe-, Mn- or Cr-tetraaryl-porphyrins, was studied.It was found that, besides epoxides, known products from such systems, allylic alcohols and aldehydes were formed, the latter not being derived from the corresponding epoxides.The relative importance of these reactions greatly depends upon both the metal and porphyrin constituents of the catalyst.More particularly, the competition between epoxidation and allylic hydroxylation can be efficiently controlled by non bonded interactions between the olefin and porphyrin substituents.No hydroxylation of the aromatic rings and no oxidative dealkylation of the ether function was detected.
New pathway for heterogenization of molecular catalysts by non-covalent interactions with carbon nanoreactors
Lebedeva, Maria A.,Chamberlain, Thomas W.,Schr?der, Martin,Khlobystov, Andrei N.
, p. 6461 - 6466 (2014)
A novel approach to heterogenization of catalytic molecules is demonstrated using the nanoscale graphitic step edges inside hollow graphitized carbon nanofibers (GNFs). The presence of the fullerene C60 moiety within a fullerene-salen CuII complex is essential for anchoring the catalyst within the GNF nanoreactor as demonstrated by comparison to the analogous catalyst complex without the fullerene group. The presence of the catalyst at the step edges of the GNFs is confirmed by high-resolution transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDX) with ultraviolet/visible (UV/vis) spectroscopy, demonstrating only negligible (ca. 3%) desorption of the fullerene-salen CuII complex from the GNFs into solution under typical reaction conditions. The catalyst immobilized in GNFs shows good catalytic activity and selectivity toward styrene epoxidation, comparable to the analogous catalyst in solution. Moreover, the fullerene-salen CuII complex in GNFs demonstrates excellent stability and recyclability because it can be readily separated from the reaction mixture and employed in multiple reaction cycles with minimal loss of activity, which is highly advantageous compared to catalysts not stabilized by the graphitic step edges that desorb rapidly from GNFs.
Convenient method for the transformation of epoxide to aldehyde and acetonide mediated by Cr-PLM
Chareonsiriwat, Laddawan,Chavasiri, Warinthorn
, p. 257 - 267 (2017)
Chromium-pillared montmorillonite (Cr-PLM) could be synthesized and efficiently utilized for styrene oxide transformations. The target aldehyde product could be quantitatively achieved from the isomerization of styrene oxide by using 10 wt% of Cr-PLM under reflux temperature for 15 min. The acetonide product could be achieved in excellent yield from the reaction of styrene oxide and acetone by using 10 wt% of Cr-PLM under room temperature for 20 min. The catalyst could be recovered and reused at least five times without loss of activity.
Synthesis, structural studies and catalytic activity of a series of dioxidomolybdenum(VI)-thiosemicarbazone complexes
Roy, Satabdi,Saswati,Lima, Sudhir,Dhaka, Sarita,Maurya, Mannar R.,Acharyya, Rama,Eagle, Cassandra,Dinda, Rupam
, p. 134 - 143 (2018)
Reaction of the thiosemicarbazone ligands, [4-(p-bromophenyl)thiosemicarbazone of salicylaldehyde (H2L1), 4-(p-X-phenyl)thiosemicarbazone of o-vanillin {X = F (H2L2), X = Cl (H2L3) and X = OMe (H2L4)}, 4-(p-bromophenyl)thiosemicarbazone of 5-bromosalicylaldehyde (H2L5), and 4-(p-chlorophenyl)thiosemicarbazone of o-hydroxynaphthaldehyde (H2L6)] with [MoO2(acac)2] afforded a series of new oxidomolybdenum(VI) complexes [Mo(VI)O2L1–6(solv)] (1–6) {where solv (solvent) = DMSO (1, 3, 5 & 6) and H2O (2 & 4)}. The molecular structures of 2 and 3 were determined by X-ray crystallography, demonstrating the dibasic tridentate behavior of ligands. The cyclic voltammogram pattern is similar for 1–6, which includes two irreversible reduction processes within the potential window ?0.71 to ?0.66 V and ?0.92 to ?0.85 V corresponding to the metal centered reduction from Mo(VI)/Mo(V) and Mo(V)/Mo(IV) respectively. Catalytic potential of 1–6 was tested for the oxidation of styrene and cyclohexene. The effect of various parameters such as the amount of catalyst, oxidant, NaHCO3, and solvent was checked to optimize the conditions for the best performance of the catalyst. 100% product selectivity for the formation of cyclohexene oxide from cyclohexene and ～98–99% product selectivity for the oxidation of styrene to styrene oxide was observed.
Activation of Nitrite Ion by Iron(III) Porphyrins. Stoichiometric Oxygen Transfer to Carbon, Nitrogen, Phosphorus, and Sulfur
Castro, Charles E.,O'Shea, Stephen K.
, p. 1922 - 1923 (1995)
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Synthesis of aldehydes from oxiranes using silica gel as reagent
Lemini,Ordonez,Perez-Flores,Cruz-Almanza
, p. 2695 - 2702 (1995)
The rearrangement of some 2-aryl monosubstituted and 2-aryl, 2-methyl disubstituted oxiranes to aldehydes using silica gel in very mild conditions is reported.
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Kabasakalian,P.,Townley,E.R.
, p. 2711 - 2716 (1962)
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Three New Polyoxoniobates Functioning as Different Oxidation Catalysts
Cui, Xiao-Bing,Li, Guanghua,Zhang, Ting-Ting
, p. 3191 - 3201 (2021)
Three new multifunctional isopolyniobates based on {Nb24O72}, namely, [Cu(en)2]9.75[Cu(en)2(H2O)]4[KNb24O72H9.25]2·36.5H2O (1), [Cu(en)2][Cu(en)2(H2O)]12[Cu(en)2(H2O)2]3[KNb24O72H7(H2O)2]2·99H2O (2), and [K(H2O)4][Cu(en)2(H2O)2]5[Cu(en)2(H2O)]8.25[Cu(en)2]2[K0.5Nb24O72H7.75]2·115.31H2O (3) (en = ethylenediamine), were obtained and characterized by IR, powder X-ray diffraction, single-crystal diffraction analysis, etc. Single-crystal analyses of the three compounds shows that all their clusters exhibit the same bowl-shaped structure, while the different transition metal complexes (TMCs) make compounds 1-3 show three entirely different packing structures. The catalytic properties of the three compounds as catalysts for Rhodamine B (RhB) photocatalytic degradation, styrene oxidation, and oxygen evolution reaction (OER) have been assessed, and all the compounds have good catalytic effects on the three different catalytic processes.
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Grigg et al.
, p. 1248 (1971)
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A Convenient Synthesis of Aldehydes by Rearrangement of Cyclic Epoxides with Lithium Bromide on Alumina
Suga, Hisashi,Miyake, Hajimu
, p. 394 - 395 (1988)
Epoxides can be converted effectively to aldehydes by rearrangement with lithium bromide supported on alumina.In the case of the alicyclic epoxides, ring contracted cycloalkanecarbaldehydes can be formed.The conversion is achieved by gas-phase reaction or in toluene as solvent.
One-Pot Synthesis of N-tert-Butylsulfinylimines and Homoallylamine Derivatives from Epoxides
Lahosa, Alejandro,Foubelo, Francisco,Yus, Miguel
, p. 4067 - 4076 (2016)
The reaction of epoxides with tert-butanesulfinamide in the presence of a Lewis acid, such as erbium triflate or boron trifluoride–diethyl ether, in THF as solvent, under microwave or thermal activation, produces N-tert-butylsulfinylimines in reasonable yields. Aromatic and gem-disubstituted and trisubstituted alkyl epoxides performed better than mono-alkyl-substituted compounds. After imine formation, a subsequent indium-promoted allylation can be carried out in the same reaction flask in a single synthetic operation leading to homoallylamine derivatives with generally high yields.
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Hickinbottom,Hogg
, p. 4200,4203 (1954)
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Kinetics and mechanism of oxidation of neutral α-amino acids by sodium N-chloro-p-toluenesulfon-amide in acid medium
Rangappa,Manjunathaswamy,Raghavendra,Made Gowda
, p. 49 - 55 (2002)
Kinetics of oxidation of α-amino acids, glycine, valine, alanine, and phenylalanine, by sodium N-chloro-p-toluenesulfonamide or chloramine-T (CAT) has been investigated in HClO4 medium at 30°C. The rate shows first-order dependence on both CAT and amino acid concentrations and an inverse first-order on [H+]. The variation of ionic strength and the addition of p-toluenesulfonamide and Cl- ion had no effect on the reaction rate. Decrease of dielectric constant of the medium by increasing the MeOH content decreased the rate. Rate studies in D2O medium showed the inverse solvent-isotope effect of kD(2)O/kH(2)O = 0.50. Proton-inventory studies were carried out using H2O-D2O mixtures. The activation parameters have been computed. The proposed mechanism and the derived rate law are consistent with the observed kinetic data. An isokinetic relationship is observed with β = 323 K, indicating enthalpy as a controlling factor. The rate of oxidation increases in the following order: Gly Val Phe Ala.
Oxidation of alcohols by iodine in the presence of nitroxyl radicals generated electrochemically
Kagan,Kashparova,Zhukova,Kashparov
, p. 745 - 747 (2010)
Oxidation of primary and secondary alcohols in the two-phase system of methylene chloride-aqueous solution of sodium hydrocarbonate in the presence of the mediator system of potassium iodide-nitroxyl radical was studied. It is supposed that under these co
Epoxidation of alkenes with aqueous hydrogen peroxide and quaternary ammonium bicarbonate catalysts
Mielby, Jerrik,Kegnaes, Soren
, p. 1162 - 1165 (2013)
A range of solid and liquid catalysts containing bicarbonate anions were synthesised and tested for the epoxidation of alkenes with aqueous hydrogen peroxide. The combination of bicarbonate anions and quaternary ammonium cations opens up for new catalytic systems that can help to overcome challenges with catalyst separation and reuse. Graphical Abstract: [Figure not available: see fulltext.]
Novelties of combustion synthesized and functionalized solid superacid catalysts in selective isomerization of styrene oxide to 2-phenyl acetaldehyde
Yadav, Ganapati D.,Gawade, Bapu A.
, p. 145 - 152 (2013)
Combustion synthesis leads to very interesting characteristics to inorganic oxides which could be further modified to render them catalytic properties. Several new approaches were studied to make a novel superacidic sulfated zirconia called fuel lean sulfated zirconia (FLSZ), by combustion synthesis. FLSZ was fully characterized and used in a reaction of industrial relevance. The isomerization of styrene oxide to 2-phenyl acetaldehyde was studied by using several solid acid catalysts. 2-Phenyl acetaldehyde finds applications in the synthesis of fine chemicals, intermediates, speciality chemicals, flavors and fragrances. Among various catalysts studied FLSZ was found to give the best activity and selectivity to 2-phenyl acetaldehyde at 100 °C using cyclohexane as a solvent. Process parameters were optimized by conducting a systematic investigation. The kinetics of the reaction was also studied. The catalyst is robust, recyclable and found to be highly active and selective. The overall process is 100% atom economical, green and clean.
KINETICS AND MECHANISM OF THE OXIDATION OF α-AMINO ACIDS BY N-BROMOACETAMIDE
Bishnoi, Mangi Lal,Banerji, Kalyan K.
, p. 6047 - 6050 (1985)
The kinetics of the oxidation of eight α-amino acids by N-bromoacetamide have been studied in aqueous perchloric acid solution.The main products of the oxidation are the corresponding carbonyl compounds.The reaction is of first order with respect to the oxidant and the amino acid.The rate of oxidation decreases linearly with an increase in hydrogen ion concentration.The rate is decreased by the addition of acetamide.The oxidation of deuteriated glycine indicated the absence of a primary kinetic isotope effect.The reaction rate has been determined at different temperatures and activation parameters have been caculated.Hypobromous acid has been postulated as the reactive oxidizing species.A rate-determining reaction of the neutral amino acid and hypobromous acid to give an N-bromo derivative has been proposed.The slow step is followed by a fast decomposition of the N-bromo derivative to yield the ultimate product.
Simple green dehydration in biphasic medium: Application to the synthesis of phenylacetaldehyde
Le Guenic, Sarah,Ceballos, Claire,Len, Christophe
, p. 72 - 77 (2016)
A highly efficient, simple and versatile acid catalyst is proposed for the selective acid dehydration of 1-phenylethan-1,2-diol to phenylacetaldehyde in water-CPME biphasic media under microwave irradiation. A high stability and recyclability of the catalyst is also observed under the investigated conditions.
Controlled light-induced release of volatile aldehydes and ketones by photofragmentation of 2-oxo-(2-phenyl)acetates
Levrand, Barbara,Herrmann, Andreas
, p. 661 - 664 (2007)
The light-induced controlled release of fragrances from photolabile 2-oxo-(2-phenyl)acetates via Norrish Type II photofragmentation was evaluated by irradiation of the precursors in different solvents and on cotton in a typical fabric softener application. The desired photooxidation was found to work efficiently in water-based systems, and it tolerates the presence of oxygen. The formation of a certain amount of alcohol besides the desired aldehyde or ketone was attributed to further reaction of the photochemically released carbonyl compound, rather than to ester hydrolysis in an aqueous environment. Schweizerische Chemische Gesellschaft.
Synthesis of meta-substituted monodentate phosphinite ligands and implication in hydroformylation ?
Deshmukh, Satej S,Gaikwad, Shahaji R,Pandey, Swechchha,Mali, Pramod S,Chikkali, Samir H
, p. 1143 - 1152 (2017)
Abstract: Synthesis of meta-substituted phosphinite ligands 3,3′-(methoxyphosphanediyl)bis(N,N- diethylaniline) (4a) and methoxybis(3-methoxyphenyl)phosphane (4b), in high yields, has been demonstrated. Typical phosphorus chemical shift between 110–120 ppm, appearance of methoxy protons and corresponding carbon, as well as ESI-MS spectra unambiguously confirmed the existence of phosphinite ligands 4a and 4b. To demonstrate the synthetic usefulness of 4a and 4b, these ligands were tested in the rhodium catalyzed hydroformylation of 1-octene. The diethylamine substituted ligand 4a was found to be highly active, whereas 4b was less reactive but revealed slightly better regioselectivity of 62% under optimized conditions. Additionally, 4a and 4b were found to catalyze the hydroformylation of styrene, 1-undecenol and 1,1-disubstituted functional olefin, methyl methacrylate. Both the ligands displayed excellent conversion of styrene, and 4b revealed an excellent branch selectivity of 75%. Although 1-undecenol proved to be amenable to hydroformylation (85–90% conversion to aldehyde), both the ligands failed to discriminate between the linear and branched products. Substrate methyl methacrylate proved to be highly challenging and reduced conversion (between 33–42%) was observed under optimized conditions. Ligand 4a was found to be highly selective towards linear aldehyde (81% linear selectivity). Graphical Abstract: Synopsis Two step synthetic protocol to access meta-substituted monodentate phosphinite ligands 3,3′-(methoxyphosphanediyl)bis(N,N-diethylaniline) (4a) and methoxybis(3-methoxyphenyl)phosphane (4b) has been developed and the ligands have been fully characterized. Apart from catalyzing the hydroformylation of benchmark substrates 1-octene and styrene, 4a and 4b were found to catalyze the hydroformylation of 1-undecenol, a functional olefin and a highly challenging 1,1-disubstituted functional olefin methyl methacrylate. [Figure not available: see fulltext.].
Flash Photolytic Decarbonylation and Ring-Opening of 2-(N-(Pentafluorophenyl)amino)-3-phenylcyclopropenone. Isomerization of the Resulting Ynamine to a Ketenimine, Hydration of the Ketenimine, and Hydrolysis of the Enamine Produced by Ring-Opening
Chiang,Grant,Guo,Kresge,Paine
, p. 5363 - 5370 (1997)
Flash photolysis of 2-(N-(pentafluorophenyl)amino)-3-phenylcyclopropenone, 4, in aqueous solution was found to produce N-(pentafluorophenyl)phenylethynamine, 3, by the expected photodecarbonylation reaction and also 2-phenyl-3-(N-(pentafluorophenyl)amino)acrylic acid, 5, by an apparently unprecedented photochemical ring-opening process. The ynamine underwent rapid isomerization to N-(pentafluorophenyl)phenylketenimine, 9, by an acid-catalyzed route that involves rate- determining proton transfer to the β-carbon atom of the ynamine and also by a base-catalyzed route involving equilibrium ionization of the N-H bond of the ynamine to give an ynamide ion followed by rate-determining β-carbon protonation of this ion. Saturation of the base catalysis allowed determination of the acidity constant of the ynamine; the result, pQa = 10.23, makes this amine a remarkably strong nitrogen acid. Hydration of the ketenimine 9 gave N-(pentafluorophenyl)phenylacetamide, 6, as the ultimate product produced by this reaction route, and hydrolysis of the aminoacrylic acid 5 gave pentafluoroaniline, 7, and 2-phenylformylacetic acid, 10, which underwent decarboxylation to phenylacetaldehyde, 8, as the ultimate products of this route.
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Naves
, p. 319 (1967)
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Highly efficient Meinwald rearrangement reactions of epoxides catalyzed by copper tetrafluoroborate
Robinson, Mathew W.C.,Pillinger, Kathryn S.,Graham, Andrew E.
, p. 5919 - 5921 (2006)
Epoxides undergo a highly efficient and selective rearrangement in the presence of catalytic quantities of copper tetrafluoroborate to give carbonyl compounds in excellent yields. The low toxicity and ease of handling of this reagent make it an attractive alternative to the more corrosive Lewis acids frequently employed.
Controlled reduction of activated primary and secondary amides into aldehydes with diisobutylaluminum hydride
Azeez, Sadaf,Kandasamy, Jeyakumar,Sabiah, Shahulhameed,Sureshbabu, Popuri
supporting information, p. 2048 - 2053 (2022/03/31)
A practical method is disclosed for the reduction of activated primary and secondary amides into aldehydes using diisobutylaluminum hydride (DIBAL-H) in toluene. A wide range of aryl and alkyl N-Boc, N,N-diBoc and N-tosyl amides were converted into the corresponding aldehydes in good to excellent yields. Reduction susceptible functional groups such as nitro, cyano, alkene and alkyne groups were found to be stable. Broad substrate scope, functional group compatibility and quick conversions are the salient features of this methodology.
Direct synthesis of 1,3-dithiolanes from terminal alkynes: Via visible light photoredox catalysis
Bhat, Ramakrishna G.,Dharpure, Pankaj D.,Khade, Vikas V.,Thube, Archana S.
supporting information, p. 1315 - 1319 (2022/02/21)
A visible light-mediated, metal-free, regioselective dihydrothionation of terminal aromatic as well as heteroaromatic alkynes has been achieved using Eosin Y as a photoredox catalyst at room temperature. The protocol gives direct access to different 1,3-dithiolanes under neutral and mild reaction conditions without the use of any base or additives. The electron-donating, electron-withdrawing and electron-deactivating groups tolerated the photocatalytic reaction conditions. The control experiments, cyclic voltammetry, and Stern-Volmer experiment were carried out to gain an insight into the mechanistic pathway. The protocol proved to be scalable at the gram level and also for practicality the deprotection of 1,3-dithiolanes has been demonstrated. The method uses clean energy under sustainable conditions. This journal is
Structural elucidation, DFT calculations and catalytic activity of dioxomolybdenum(VI) complexes with N–N donor ligand: Role of halogen atom coordinated to the molybdenum centre
Roy, Malini,Biswal, Debanjana,Pramanik, Nikhil Ranjan,Drew, Michael G.B.,Paul, Suvendu,Kachhap, Payal,Haldar, Chanchal,Chakrabarti, Syamal
, (2021/03/22)
Two new isostructural mononuclear dioxomolybdenum(VI) complexes of the formula MoO2X2L [where, X = Cl (1), Br (2)] have been synthesized with a N–N donor 2-(3-methyl-5-phenyl pyrazol-1-yl) benzthiazole ligand (L). The reaction is carried out in open air and the MoVO3+ centre in the precursor molecule, MoOX3L undergoes spontaneous aerial oxidation, leading to the formation of molybdenum(VI) complexes 1 and 2. The complexes are characterized by a wide range of spectroscopic techniques (IR, UV–Vis and 1H NMR) and elemental analyses. Crystal structures of the ligand and complexes 1 and 2 have been determined by single crystal X-ray diffraction which reveal a distorted octahedral geometry around the molybdenum(VI) centre in both the complexes. The ligand and the complexes build up fascinating supramolecular assembly via several non-covalent interactions including hydrogen bonding, C–H···π and π···π interactions. Further, a detailed study of Hirshfeld surface analysis and fingerprint plots of complexes 1 and 2 are presented for understanding the intermolecular interactions involved in building self-assembled frameworks. Supportive DFT and TD-DFT calculations have also been carried out. Electrochemical properties of the complexes have been examined by cyclic voltammetry. Catalytic performance of the synthesized complexes has been evaluated for the oxidation of different olefins in the presence of hydrogen peroxide.
