119-61-9Relevant articles and documents
Substituent and Solvent Effects in the Reactions of Diaryldiazomethanes with 2,3-Dichloro-5,6-dicyanobenzoquinone
Oshima, Takumi,Nagai, Toshikazu
, p. 2039 - 2044 (1981)
Kinetic studies have been made of the reactions of fifteen meta- and para-substituted diphenyldiazomethanes(DDMs) with 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) in benzene.The second order rate constants, k, increased with the electron-donability of the substituents, and the value could be correlated with the Yukawa-Tsuno equation: log k/k0 = -2.33(?0 + 0.47Δ+) + 0.017, (r = 0.996, 30 deg C).The ρ value, -2.33, indicates the development of a positive charge at the diazo carbon in the transition state, while the R value, 0.47, confirms the moderate stabilization of the positive charge by the ?-electronic contribution of the para substituents.The rate constants have also been determined for the reaction of diphenyldiazomethane(DDM) with DDQ in 28 aprotic solvents.The effects of solvents can be interpreted in terms of the basicity and the steric nature of the solvents.The products of these reactions were poly(2,3-dichloro-5,6-dicyanohydroquinone benzhydryl ether)s, which were easily convertible into benzophenones and α,α-dimethoxydiphenylmethane, together with 2,3-dichloro,5,6-dicyanohydroquinone, under the influence of water and methanol.These solvolysis products were also obtained in excellent yields in the initial presence of these additives.
Oxovanadium(v)-catalyzed deoxygenative homocoupling reaction of alcohols
Sakuramoto, Takashi,Donaka, Yosuke,Tobisu, Mamoru,Moriuchi, Toshiyuki
, p. 17571 - 17576 (2019)
Oxovanadium(v)-catalyzed transformation of alcohols in the presence of hydrazine derivatives was demonstrated. The direct hydrazination reaction of 1,3-diphenylprop-2-en-1-ol with 1,1-diphenylhydrazine in the presence of VO(OSiPh3)3 as a catalyst and MS3A as a dehydrating reagent proceeded to afford the corresponding hydrazination product. On the contrary, the utilization of 1,1-dimethylhydrazine instead of 1,1-diphenylhydrazine was found to induce the deoxygenative homocoupling reaction of the allyl alcohol to give the corresponding 1,5-diene as a major product. In addition to the deoxygenative homocoupling product, the allyl amine into which aniline was introduced was also obtained by using 1,2-diphenylhydrazine in the reaction of 1,3-diphenyl-2-methylprop-2-en-1-ol. Oxovanadium(v)-catalyzed deoxygenative homocoupling reaction of benzyl alcohols could also be performed in the presence of 1,1-dimethylhydrazine.
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Kharasch,Nudenberg,Archer
, p. 495,497 (1943)
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Co(ii)-cluster-based metal-organic frameworks as efficient heterogeneous catalysts for selective oxidation of arylalkanes
Fan, Yanru,Li, Xiao,Gao, Kuan,Liu, Yu,Meng, Xiangru,Wu, Jie,Hou, Hongwei
, p. 1666 - 1673 (2019)
To explore metal-organic frameworks (MOFs) based on Co-clusters as heterogeneous catalysts to selectively catalyze the reaction of C-H bond oxidation of aromatic alkanes to their corresponding ketones, three MOFs {[Co5(pmbcd)2(μ3-OH)2(H2O)4(DMF)2]·4DMF}n (MOF 1), {[Co2(pmbcd)(bpea)2]·2H2O·2DMF}n (MOF 2), and {[Co2(pmbcd)(dpp)2]·3H2O·2DMF}n (MOF 3) (H4pmbcd = 9,9′-(1,4-phenylenebis(methylene))bis(9H-carbazole-3,6-dicarboxylic acid), bpea = 1,2-bis(4-pyridyl)ethane, dpp = 1,3-di(4-pyridyl)propane) were successfully synthesized and structurally characterized. MOF 1 was constructed from a pentanuclear Co(ii) cluster and exhibited a porous framework with channels of 8 × 10 ?2 along the b axis. MOF 2 was constructed from [Co2(CO2)4] units and presented a porous three-dimensional (3D) framework with channels of 11 × 13 ?2 along the b axis and of 10 × 12 ?2 along the c axis. MOF 3 was a flat two-dimensional (2D) layer based on binuclear Co(ii) units when dpp as an auxiliary ligand was introduced. The Co5-cluster-based MOF 1 exhibited excellent catalytic activity for the direct C-H bond activation of arylalkanes to ketones in H2O under room temperature because of its high density of Lewis acidic sites within the frameworks and suitable channel size to access the catalytic sites. It also presented the spatial confinement effect and catalyzed the reaction with high regioselectivity, forming mono-ketones as the sole products. Easy product separation, simple reaction procedures, and recyclability of these catalysts make the catalytic system attractive. Our work highlights the superiority of the MOF-based materials as heterogeneous catalysts.
Ionic liquid [bmim]Br assisted chemoselective benzylic [Formula presented] oxidations using tert-butyl hydroperoxide
Naidu, Shivaji,Reddy, Sabbasani Rajasekhara
, p. 441 - 445 (2016)
A mild and efficient, ionic-liquid-assisted green protocol for the chemoselective oxygenation of benzylic C-H bonds to corresponding ketones using ionic liquid [bmim]Br with tert-butyl hydroperoxide has been developed. The method reported in this paper has the advantages of [bmim]Br acting as recyclable solvent and reagent. The usage of additives such as acids or bases and metal salts is not required. The developed strategy is further extended to oxidation of secondary alcohols to respective ketones under similar optimized reaction conditions.
Thiol ester-boronic acid cross-coupling. Catalysis using alkylative activation of the palladium thiolate intermediate
Savarin, Cecile,Srogl, Jiri,Liebeskind, Lanny S.
, p. 3229 - 3231 (2000)
(matrix presented) Thiol esters and boronic acids do not participate in cross-coupling in the presence of palladium catalysts. However, efficient palladium-catalyzed thiol ester-boronic acid cross-coupling is observed when simple alkylating agents are present. Alkylative conversion of the very stable palladium-thiolate bond to a labile palladium-thioether bond is presumed to be crucial to the catalysis. Of the systems studied, 4-halo-n-butyl thiol esters were most effective in this cross-coupling.
Product selectivity in semiconductor-mediated dehydrazonation of benzophenone hydrazone
Krishnakumar,Selvam,Swaminathan
, p. 1929 - 1937 (2011)
Product selectivity in the dehydrazonation of benzophenone hydrazone by photocatalytic oxidation with various semiconductor photocatalysts has been investigated using ultraviolet-A light. TiO2-P25 shows greater product selectivity of benzophenone formation with 93.9% conversion. Doping of metals on TiO2 selectively enhances the formation of azine from hydrazone. Solvents such as dichloromethane, chloroform, and dichloroethane also enhance the formation of azine.
Heteropolytungstic acids incorporated in an ordered mesoporous zirconia framework as efficient oxidation catalysts
Skliri, Euaggelia,Lykakis, Ioannis N.,Armatas, Gerasimos S.
, p. 8402 - 8409 (2014)
Ordered mesoporous composite catalysts consisting of nanocrystalline tetragonal ZrO2 and heteropolytungstic clusters, i.e. 12-phosphotungstic (PTA) and 12-silicotungstic (STA) acids, were prepared via a surfactant-assisted co-polymerization route. According to the X-ray diffraction, transmission electron microscopy and N2 physisorption measurements, the resultant materials possess a well-defined mesoscopic order ranging from wormhole to hexagonal pore structure and exhibit large internal surface area (126-229 m2 g-1) and quite narrow pore size distribution (ca. 2.2-2.6 nm in diameter). Energy dispersive X-ray microanalysis and infrared spectroscopy confirms that the heteropoly clusters are well dispersed within the zirconia matrix, while preserving intact their Keggin structure. The inclusion of PTA and STA clusters in the mesoporous framework has a beneficial effect on the catalytic activity of these materials. Although zirconium oxide and heteropoly acids alone show little catalytic activity, the ZrO 2-PTA and ZrO2-STA heterostructures exhibit surprisingly high activity in hydrogen peroxide mediated oxidation of 1,1-diphenyl-2- methylpropene under mild conditions. Indeed, the mesoporous ZrO2-STA composite sample loaded with 5 wt% STA shows a conversion rate that is 17 times higher than the mesoporous ZrO2. The catalytic activity of these materials is related to the spatial distribution of heteropoly acids in zirconia matrix and possible synergistic interactions between the incorporated Keggin units and Zr(iv) oxohydroxide species.
Use of Isopropyl Alcohol as a Reductant for Catalytic Dehydoxylative Dimerization of Benzylic Alcohols Utilizing Ti?O Bond Photohomolysis
Iwasawa, Nobuharu,Sumiyama, Keiichi,Toriumi, Naoyuki
, p. 2474 - 2478 (2021)
Photohomolysis of Ti?O bonds is utilized in photocatalytic generation of titanium(III) species for dehydroxylative dimerization of benzylic alcohols under UV-light irradiation by using isopropyl alcohol (IPA) as a stoichiometric reductant. In this reaction, IPA works not as a single-electron donor as in the photo-redox catalyzed reactions but as an H-atom-donor. The reaction also proceeds under visible-light irradiation in the presence of thioglycolic acid as a ligand.
Sisti,Milstein
, p. 2408 (1973)
Oxidation of Benzylic Methylene Compounds to Ketones with 4-Aminoperoxybenzoic Acid Supported on Silica Gel in Presence of Oxygen or Air
Hashemi, Mohammed M.,Ghazanfari, Dadkhoda,Karimi-Jaberi, Zahed
, p. 185 - 188 (2004)
4-Aminoperoxybenzoic acid supported on silica gel in presence of oxygen or air was found to be a convenient and selective oxidant for the oxidation of benzylic methylene compounds to the corresponding ketones.
A Tale of Copper Coordination Frameworks: Controlled Single-Crystal-to-Single-Crystal Transformations and Their Catalytic C-H Bond Activation Properties
Chen, Yifa,Feng, Xiao,Huang, Xianqiang,Lin, Zhengguo,Pei, Xiaokun,Li, Siqing,Li, Jikun,Wang, Shan,Li, Rui,Wang, Bo
, p. 13894 - 13899 (2015)
Metal-organic frameworks (MOFs), as a class of microporous materials with well-defined channels and rich functionalities, hold great promise for various applications. Yet the formation and crystallization processes of various MOFs with distinct topology, connectivity, and properties remain largely unclear, and the control of such processes is rather challenging. Starting from a 0D Cu coordination polyhedron, MOP-1, we successfully unfolded it to give a new 1D-MOF by a single-crystal-to-single-crystal (SCSC) transformation process at room temperature as confirmed by SXRD. We also monitored the continuous transformation states by FTIR and PXRD. Cu MOFs with 2D and 3D networks were also obtained from this 1D-MOF by SCSC transformations. Furthermore, Cu MOFs with 0D, 1D, and 3D networks, MOP-1, 1D-MOF, and HKUST-1, show unique performances in the kinetics of the C-H bond catalytic oxidation reaction.
Fabrication of CuCr2O4 spinel nanoparticles: A potential catalyst for the selective oxidation of cycloalkanes via activation of Csp3-H bond
Acharyya, Shankha S.,Ghosh, Shilpi,Adak, Shubhadeep,Tripathi, Deependra,Bal, Rajaram
, p. 145 - 150 (2015)
We report here preparation of CuCr2O4 spinel nanoparticle catalyst, mediated by cationic surfactant CTAB in hydrothermal route. XRD revealed the formation of CuCr2O4 spinel phase and TEM showed the particle size of 30-60 nm. The catalyst was speculated to be highly active for selective oxidation of cyclohexane to cyclohexanone with H2O2. A cyclohexane conversion of 70% with 85% cyclohexanone selectivity was achieved over this catalyst at 50 °C temperature. Moreover, the catalyst did not show any significant activity loss even after 8 reuses and proved its efficacy in the oxidation of other cycloalkanes also.
Ayres,Hauser
, p. 116,118 (1948)
Bioinspired oxidation of oximes to nitric oxide with dioxygen by a nonheme iron(II) complex
Bhattacharya, Shrabanti,Lakshman, Triloke Ranjan,Sutradhar, Subhankar,Tiwari, Chandan Kumar,Paine, Tapan Kanti
, p. 3 - 11 (2020)
The ability of two iron(II) complexes, [(TpPh2)FeII(benzilate)] (1) and [(TpPh2)(FeII)2(NPP)3] (2) (TpPh2 = hydrotris(3,5-diphenylpyrazol-1-yl)borate, NPP-H = α-isonitrosopropiophenone), of a monoanionic facial N3 ligand in the O2-dependent oxidation of oximes is reported. The mononuclear complex 1 reacts with dioxygen to decarboxylate the iron-coordinated benzilate. The oximate-bridged dinuclear complex (2), which contains a high-spin (TpPh2)FeII unit and a low-spin iron(II)–oximate unit, activates dioxygen at the high-spin iron(II) center. Both the complexes exhibit the oxidative transformation of oximes to the corresponding carbonyl compounds with the incorporation of one oxygen atom from dioxygen. In the oxidation process, the oxime units are converted to nitric oxide (NO) or nitroxyl (HNO). The iron(II)–benzilate complex (1) reacts with oximes to afford HNO, whereas the iron(II)–oximate complex (2) generates NO. The results described here suggest that the oxidative transformation of oximes to NO/HNO follows different pathways depending upon the nature of co-ligand/reductant.
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Gilman,St. John
, p. 1172,1176 (1930)
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Kinetic studies of lipid phase autoxidation of diphenylmethane
Okada,Kitamura,Hayakawa
, p. 281 - 289 (1971)
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Rh-catalyzed carbonylation of arylzinc compounds yielding symmetrical diaryl ketones by the assistance of oxidizing agents
Kobayashi, Kana,Nishimura, Yugo,Gao, Fuxing,Gotoh, Kazuma,Nishihara, Yasushi,Takagi, Kentaro
, p. 1949 - 1952 (2011)
Carbonylative homocoupling of arylzinc compounds 1 using 1 atm of CO and 1,2-dibromoethane as an oxidant was achieved in the presence of Rh-dppf catalyst, affording symmetrical diaryl ketones in good yields. Under similar conditions, Pd or Ni catalysts induced oxidative homocoupling of 1 to yield biaryls instead. The beneficial catalysis by Rh in the carbonylation was presumed to stem from the facility by which the migration of the aryl ligand to CO at the Rh3+ intermediate occurred.
Liquid phase oxidation of diphenylmethane to benzophenone with molecular oxygen over nano-sized Co-Mn catalyst supported on calcined Cow bone
Monjezi,Yazdani,Mokfi,Ghiaci
, p. 58 - 63 (2014)
A well-dispersed Co-Mn catalyst immobilized on calcined Cow bone was synthesized and used, for the first time for the selective synthesis of benzophenone by liquid phase oxidation of diphenylmethane under various reaction conditions. The catalyst was characterized using techniques such as UV-vis, SEM, TEM and BET. The catalyst has shown an excellent activity (87%), selectivity to diphenyl ketone (90%) and stability under solvent free conditions. To investigate the leaching of the metals from the support, results of the original and reusable catalyst was correlated and compared, and the catalytic activity of washed catalyst was also demonstrated. Based on the all catalytic results for this reaction, the new catalyst was found to be a highly active and environmentally friendly solid catalyst and has superior catalytic activity.
Chloro-ruthenium complexes with carbonyl and N-(aryl)pyridine-2-aldimines as ancillary ligands. Synthesis, characterization and catalytic application in C-C cross-coupling of arylaldehydes with arylboronic acids
Dey, Bikash Kali,Dutta, Jayita,Drew, Michael G.B.,Bhattacharya, Samaresh
, p. 176 - 184 (2014)
Reaction of N-(aryl)pyridine-2-aldimines (L-R, R = OCH3, CH 3, H, Cl and NO2) with [Ru(CO)2Cl 2]n in refluxing ethanol affords a group of complexes of type [Ru(L-R)(CO)2Cl2]. In these complexes the diimine ligands (L-R) are coordinated to the metal center as NN-donors forming five-membered chelate rings, the carbonyls are mutually cis and the two chlorides are trans. Crystal structure of [Ru(L-OCH3)(CO) 2Cl2] has been determined. All the complexes show characteristic 1H NMR signals, and in dichloromethane solution they display intense absorptions in the visible and ultraviolet regions. Cyclic voltammetry on the complexes shows an irreversible oxidation of the metal center within 1.15-1.23 V vs SCE, and reduction(s) of the diimine ligand within -0.70 to -0.96 V vs SCE. The [Ru(L-R)(CO)2Cl2] complexes efficiently catalyze cross-coupling of arylaldehydes with arylboronic acids yielding diaryl ketones.
Clean and efficient benzylic C-H oxidation using a microflow system
Lv, Xiao-Ming,Kong, Ling-Jie,Lin, Qi,Liu, Xiao-Feng,Zhou, Ya-Ming,Jia, Yu
, p. 3215 - 3222 (2011)
An efficient procedure using microreactors for the oxidation of benzylic compounds is described. This new method is facile, economical, and environmentally friendly. By using microreactors, this oxidation can be accomplished with good yields within 10s at room temperature. Copyright
Reactions in Dry Media: Oxidative Cleavage of Olefins Adsorbed on Inorganic Supports with Oxygen
Aronovitch, Chaim,Mazur, Yehuda
, p. 149 - 150 (1985)
Substituted phenylethylenes adsorbed on inorganic supports are oxidatively cleaved to ketones or aldehydes under illumination in the presence of oxygen.It is suggested that these oxidations invove the intermediacy of cation radicals whose formation is initiated by contact charge-transfer interactions between the olefins on the adsorbing phase and oxygen molecules.
Alkyl Hydroperoxide Oxidation of Alkanes and Alkenes with a Highly Active Mn Catalyst
Sarneski, Joseph E.,Michos, Demetrius,Thorp, H. Holden,Didiuk, Mary,Poon, Thomas,et al.
, p. 1153 - 1156 (1991)
The system ROOH/(ClO4)4 hydroxylates alkanes and converts ArCR=CH2 to ArCR=O with extremely high activity and good conversions and yields.
Formation of an Ozonide by Electron-Transfer Photooxygenation of Tetraphenyloxirane. Cosensitization by 9,10-Dicyanoanthracene and Biphenyl
Schaap, A. Paul,Lopez, Luigi,Gagnon, Steven D.
, p. 663 - 664 (1983)
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Structural Effects of Olefins in the Photooxygenation with Electron-Accepting Sensitizers. Kinetic Approach to Reactive Intermediates
Konuma, Satoshi,Aihara, Shin,Kuriyama, Yasunao,Misawa, Hiroaki,Akaba, Ryoichi,et al.
, p. 1897 - 1900 (1991)
Pulsed laser excitation studies on the reactive species in 9-cyanoanthracene(CNA)-sensitized oxygenation of 1,1-diphenyl-2-methylpropene (1a) and (E)-2,3-diphenyl-2-butene (1b) show that the reaction course is mostly governed by competitive quenching of the CNA excited singlet by 1 and oxygen to produce 1+. and 1O2, respectively.The results indicate that the reaction courses of tetraphenylethylene and 2,3-dimethyl-2-butene, for example, can be explaind by exclusive quenching of sensitizer singlets by the olefin and oxygen, respectively.
HCl-Catalyzed Aerobic Oxidation of Alkylarenes to Carbonyls
Niu, Kaikai,Shi, Xiaodi,Ding, Ling,Liu, Yuxiu,Song, Hongjian,Wang, Qingmin
, (2021/12/13)
The construction of C?O bonds through C?H bond functionalization remains fundamentally challenging. Here, a practical chlorine radical-mediated aerobic oxidation of alkylarenes to carbonyls was developed. This protocol employed commercially available HCl as a hydrogen atom transfer (HAT) reagent and air as a sustainable oxidant. In addition, this process exhibited excellent functional group tolerance and a broad substrate scope without the requirement for external metal and oxidants. The mechanistic hypothesis was supported by radical trapping, 18O labeling, and control experiments.
Radical Alkene-Trifluoromethylation-Triggered Nitrile Insertion/Remote Functionalization Relay Processes: Diverse Synthesis of Trifluoromethylated Azaheterocycles Enabled by Copper Catalysis
Li, Wen-Cheng,Liao, Wei-Wei,Sun, Yun-Hai,Wei, Zhong-Lin,Wu, Yu-Heng,Xi, Ji-Ming
supporting information, p. 1110 - 1115 (2022/02/10)
A copper-catalyzed alkene-trifluoromethylation-triggered nitrile insertion/remote functionalization relay process has been achieved, in which "interrupted"remote 1,n-difunctionalizations of alkenes with nitrile insertion can deliver iminyl radical interme
Microwave Assisted Oxidation of Benzyl Halides to Aldehydes and Ketones with 4-Hydroxypyridinium Nitrate Functionalized Silica Gel in Aqueous Media
Ghalehbandi, Shermineh sadat,Ghazanfari, Dadkhoda,Ahmadi, Sayed Ali,Sheikhhosseini, Enayatollah
, p. 176 - 183 (2021/04/29)
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