- Preparation, characterization and catalytic performance of bimetallic Ti-Co-MCM-41 catalysts
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Ti-Co-MCM-41 molecular sieve catalysts were synthesized using the impregnation method. The catalysts were characterized by X-ray diffraction, UV-visible, Fourier transform infrared spectroscopy and low temperature N2 adsorption-desorption. Their performance in 4-tert-butylbenzaldehyde synthesis was evaluated in mild conditions by oxygen oxidation 4-tert-butyltoluene. The results showed that the catalysts had large surface area and pore size and contained titanium and cobalt with four ligands, which formed the catalysts of high catalytic activity. The conversion rate of 4-tert-butyl toluene was improved by 38%, the selectivity of 4-tert-butyl benzaldehyde was improved by 85% and the yield of 4-tert-butyl benzaldehyde was up to 35%.
- Zhang, Jinfeng,Zhang, Jiyao,Zhao, Jianshe,Zhang, Cunshe,Shen, Hanxi,Zhou, Kui
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- Liquid phase selective oxidation of aromatic alcohols employing nanoparticles of Zirconia supported on nickel manganese oxide: Synthesis, characterization and catalytic evaluation
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Zirconia nanoparticles supported on nickel manganese mixed oxide were synthesized by co-precipitation method. The catalytic properties of these materials were investigated for the oxidation of benzyl alcohol using molecular oxygen as oxidant. It was obser
- Alabbad, Saad,Adil,Alwarthan, Abdulrahman,Siddiqui, M. Rafiq H.
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- Selective oxidation of benzylic alcohols with molecular oxygen catalyzed by copper-manganese oxide nanoparticles
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The catalytic activity of copper-manganese (CuMn) mixed oxide nanoparticles (Cu/Mn = 1:1) prepared by co-precipitation method has been studied for the selective oxidation of benzyl alcohol and its derivatives to the corresponding aldehydes using molecular
- Ali, Roushown,Assal,Al-Warthan, Abdulrahman,Rafiq,Siddiqui
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- The selective oxidation of benzyl alcohols in a membrane reactor
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The selective oxidation of benzyl alcohols by hypochlorite and a phase transfer catalyst has been successfully carried out in a membrane reactor.
- Grigoropoulou,Clark,Hall,Scott
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Read Online
- Gold nanoparticles on hydrotalcites as efficient catalysts for oxidant-free dehydrogenation of alcohols
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Hydrotalcite-supported gold nanoparticles with sizes of less than 5 nm are highly efficient and reusable catalysts for the oxidant-free dehydrogenation of alcohols to carbonyl compounds and hydrogen. The Royal Society of Chemistry 2010.
- Fang, Wenhao,Zhang, Qinghong,Chen, Jing,Deng, Weiping,Wang, Ye
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- Inhibition of the Cobalt Acetate/Bromide-Catalyzed Hydrogen Peroxide Oxidation of 4-tert-Butyltoluene
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The hydrogen peroxide oxidation of 4-tert-butyltoluene to 4-tert-butylbenzaldhyde, an important fragrance intermediate, catalyzed by cobalt acetate and bromide in acetic acid was investigated again. The initial stages of the reaction appear to be rapid and quantitative, but after approximately 25-30% conversion, the process ceases. Overoxidation to 4-tert-butylbenzoic acid does not occur. It appears that both water and the aldehyde product itself inhibit further oxidation. An engineering solution to remove the product continuously seems required for process optimization.
- Amin, Ahmed A.,Beattie, James K.
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- Functionalized-1,3,4-oxadiazole ligands for the ruthenium-catalyzed Lemieux-Johnson type oxidation of olefins and alkynes in water
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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.
- Hkiri, Shaima,Touil, Soufiane,Samarat, Ali,Sémeril, David
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- A Metal–Organic Framework as a Multiphoton Excitation Regulator for the Activation of Inert C(sp3)?H Bonds and Oxygen
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The activation and oxidization of inert C(sp3)?H bonds into value-added chemicals affords attractively economic and ecological benefits as well as central challenge in modern chemistry. Inspired by the natural enzymatic transformation, herein,
- Cai, Junkai,Cai, Wei,Du, Zenggang,Duan, Chunying,He, Cheng,Ji, Guanfeng,Wei, Jianwei,Zhao, Liang
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supporting information
(2021/11/27)
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- Controlled reduction of activated primary and secondary amides into aldehydes with diisobutylaluminum hydride
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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.
- Azeez, Sadaf,Kandasamy, Jeyakumar,Sabiah, Shahulhameed,Sureshbabu, Popuri
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supporting information
p. 2048 - 2053
(2022/03/31)
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- Merging N-Hydroxyphthalimide into Metal-Organic Frameworks for Highly Efficient and Environmentally Benign Aerobic Oxidation
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Two highly efficient metal-organic framework catalysts TJU-68-NHPI and TJU-68-NDHPI have been successfully synthesized through solvothermal reactions of which the frameworks are merged with N-hydroxyphthalimide (NHPI) units, resulting in the decoration of pore surfaces with highly active nitroxyl catalytic sites. When t-butyl nitrite (TBN) is used as co-catalyst, the as-synthesized MOFs are demonstrated to be highly efficient and recyclable catalysts for a novel three-phase heterogeneous oxidation of activated C?H bond of primary and secondary alcohols, and benzyl compounds under mild conditions. Based on the high efficiency and selectivity, an environmentally benign system with good sustainability, mild conditions, simple work-up procedure has been established for practical oxidation of a wide range of substrates.
- Wang, Man,Liang, Gan,Wang, Yunhao,Fan, Tao,Yuan, Baoling,Liu, Mingxian,Yin, Ying,Li, Liangchun
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supporting information
p. 9674 - 9685
(2021/06/09)
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- An aerobic oxidation of alcohols into carbonyl synthons using bipyridyl-cinchona based palladium catalyst
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We have reported an aerobic oxidation of primary and secondary alcohols to respective aldehydes and ketones using a bipyridyl-cinchona alkaloid based palladium catalytic system (PdAc-5) using oxygen at moderate pressure. ThePdAc-5catalyst was analysed using SEM, EDAX, and XPS analysis. The above catalytic system is used in experiments for different oxidation systems which include different solvents, additives, and bases which are cheap, robust, non-toxic, and commercially available on the industrial bench. The obtained products are quite appreciable in both yield and selectivity (70-85%). In addition, numerous important studies, such as comparisons with various commercial catalysts, solvent systems, mixture of solvents, and catalyst mole%, were conducted usingPdAc-5. The synthetic strategy of oxidation of alcohol into carbonyl compounds was well established and all the products were analysed using1H NMR,13CNMR and GC-mass analyses.
- Cheedarala, Ravi Kumar,Chidambaram, Ramasamy R.,Siva, Ayyanar,Song, Jung Il
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p. 32942 - 32954
(2021/12/02)
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- Method for generating benzaldehyde by catalyzing alpha-monosubstituted styrene to be oxidized by N-hydroxyphthalimide
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The invention discloses a method for generating benzaldehyde by catalyzing alpha-mono-substituted styrene to be oxidized through N-hydroxyphthalimide. According to the method, N-hydroxyphthalimide isused as a catalyst, oxygen is used as an oxidizing agent, and an alpha mono-substituted styrene compound is oxidized in an organic solvent to obtain the benzaldehyde derivative. The method has the advantages of simple reaction operation, low cost, mild conditions, high yield, no heavy metal pollution and the like.
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Paragraph 0025-0032
(2021/01/24)
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- V2O5@TiO2 Catalyzed Green and Selective Oxidation of Alcohols, Alkylbenzenes and Styrenes to Carbonyls
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The versatile application of different functional groups such as alcohols (1° and 2°), alkyl arenes, and (aryl)olefins to construct carbon-oxygen bond via oxidation is an area of intense research. Here, we report a reusable heterogeneous V2O5@TiO2 catalyzed selective oxidation of various functionalities utilizing different mild and eco-compatible oxidants under greener reaction conditions. The method was successfully applied for the alcohol oxidation, oxidative scission of styrenes, and benzylic C?H oxidation to their corresponding aldehydes and ketones. The utilization of mild and eco-friendly oxidizing reagents such as K2S2O8, H2O2 (30 % aq.), TBHP (70 % aq.), broad substrate scope, gram-scale synthesis, and catalyst recyclability are notable features of the developed protocol.
- Upadhyay, Rahul,Kumar, Shashi,Maurya, Sushil K.
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p. 3594 - 3600
(2021/07/02)
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- Photo-induced oxidative cleavage of C-C double bonds for the synthesis of biaryl methanoneviaCeCl3catalysis
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A Ce-catalyzed strategy is developed to produce biaryl methanonesviaphotooxidative cleavage of C-C double bonds at room temperature. This reaction is performed under air and demonstrates high activity as well as functional group tolerance. A synergistic Ce/ROH catalytic mechanism is also proposed based on the experimental observations. This protocol should be the first successful Ce-catalyzed photooxidation reaction of olefins with air as the oxidant, which would provide inspiration for the development of novel Ce-catalyzed photochemical synthesis processes.
- Xie, Pan,Xue, Cheng,Du, Dongdong,Shi, SanShan
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supporting information
p. 6781 - 6785
(2021/08/20)
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- Hydroxyl radical-mediated oxidative cleavage of CC bonds and further esterification reaction by heterogeneous semiconductor photocatalysis
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A hydroxyl radical-mediated aerobic cleavage of alkenes and further sequence esterification reaction for the preparation of carbonyl compounds have been developed by using tubular carbon nitride (TCN) as a general heterogeneous photocatalyst under an oxygen atmosphere with visible light irradiation. This protocol has an excellent substrate scope and gives the desired aldehydes, ketones and esters in moderate to high yields. Importantly, this metal-free procedure employed photogenerated hydroxyl radicals in situ as green oxidation active species, avoiding the present additional initiators. The reaction could be carried out under solar light irradiation and was applicable to large-scale reactions. Furthermore, the recyclable TCN catalyst could be used several times without a significant loss of activities.
- Hong, Mei,Jia, Rui,Miao, Hongyan,Ni, Bangqing,Niu, Tengfei,Wang, Hui
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p. 6591 - 6597
(2021/09/10)
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- Decatungstate-mediated solar photooxidative cleavage of CC bonds using air as an oxidant in water
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With the increasing attention for green chemistry and sustainable development, there has been much interest in searching for greener methods and sources in organic synthesis. However, toxic additives or solvents are inevitably involved in most organic transformations. Herein, we first report the combination of direct utilization of solar energy, air as the oxidant and water as the solvent for the selective cleavage of CC double bonds in aryl olefins. Various α-methyl styrenes, diaryl alkenes as well as terminal styrenes are well tolerated in this green and sustainable strategy and furnished the desired carbonyl products in satisfactory yields. Like heterogeneous catalysis, this homogeneous catalytic system could also be reused and it retains good activity even after repeating three times. Mechanism investigations indicated that both O2- and 1O2 were involved in the reaction. Based on these results, two possible mechanisms, including the electron transfer pathway and the energy transfer pathway, were proposed.
- Du, Dongdong,Luo, Junfei,Shi, Sanshan,Xie, Pan,Xue, Cheng
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p. 5936 - 5943
(2021/08/23)
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- A highly stable metal-organic framework with cubane-like clusters for the selective oxidation of aryl alkenes to aldehydes or ketones
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Triazine derivatives, a class of electron-deficient π-conjugated molecules with high photochemical activity and excellent luminescent characteristics, have been utilized as a kind of electron-acceptor for the construction of molecular cages, luminescent and photochromic materials. In this paper, a novel and highly stable MOF with cubane-like clusters, [Co4(SO4)3(F)3(tpt)2(tatb)] (1) (tpt = 2,4,6-tris-(4-pyridyl)-1,3,5-triazine, H3tatb = 4,4′,4′′-(1,3,5-triazine-2,4,6-triyl)tribenzoic acid), has been successfully synthesized based on a triazine derivative, and possesses unprecedented sulfate- and fluoride-bridged cubane-type tetranuclear cobalt clusters and a 3D + 3D → 3D open framework. Compound1shows a rather high BET surface area and exhibits excellent thermal stability and high chemical stability in common solvents and even in acidic or basic solutions (in a pH range from 4 to 12). Moreover, catalytic measurements show that compound1is an excellent heterogeneous catalyst for the selective oxidation of aryl alkenes to aldehydes or ketones with conversions of 97%.
- He, Chixian,Liu, Jiaming,Liu, Jian-Jun,Liu, Teng,Shen, Xianfu,Shen, Xiang
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p. 4667 - 4673
(2021/07/11)
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- Visible-Light-Driven Oxidative Cleavage of Alkenes Using Water-Soluble CdSe Quantum Dots
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The oxidative cleavage of C=C bonds is an important chemical reaction, which is a popular reaction in the photocatalytic field. However, high catalyst-loading and low turnover number (TON) are general shortcomings in reported visible-light-driven reactions. Herein, the direct oxidative cleavage of C=C bonds through water-soluble CdSe quantum dots (QDs) is described under visible-light irradiation at room temperature with high TON (up to 3.7×104). Under the same conditions, water-soluble CdSe QDs could also oxidize sulfides to sulfoxides with 51–84 % yields and TONs up to 3.4×104. The key features of this photocatalytic protocol include high TONs, wide substrates scope, low catalyst loadings, simple and mild reaction conditions, and molecular O2 as the oxidant.
- Li, Jianing,Zhao, Jingnan,Ma, Cunfei,Yu, Zongyi,Zhu, Hongfei,Yun, Lei,Meng, Qingwei
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p. 4985 - 4992
(2021/10/16)
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- Selective Electrochemical Oxygenation of Alkylarenes to Carbonyls
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An efficient electrochemical method for benzylic C(sp3)-H bond oxidation has been developed. A variety of methylarenes, methylheteroarenes, and benzylic (hetero)methylenes could be converted into the desired aryl aldehydes and aryl ketones in moderate to excellent yields in an undivided cell, using O2 as the oxygen source and lutidinium perchlorate as an electrolyte. On the basis of cyclic voltammetry studies, 18O labeling experiments, and radical trapping experiments, a possible single-electron transfer mechanism has been proposed for the electrooxidation reaction.
- Li, Xue,Bai, Fang,Liu, Chaogan,Ma, Xiaowei,Gu, Chengzhi,Dai, Bin
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supporting information
p. 7445 - 7449
(2021/10/02)
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- Metal- And additive-free C-H oxygenation of alkylarenes by visible-light photoredox catalysis
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A metal- and additive-free methodology for the highly selective, photocatalyzed C-H oxygenation of alkylarenes under air to the corresponding carbonyls is presented. The process is catalyzed by an imide-acridinium that forms an extremely strong photooxidant upon visible light irradiation, which is able to activate inert alkylarenes such as toluene. Hence, this is an easy to perform, sustainable and environmentally friendly oxidation that provides valuable carbonyls from abundant, readily available compounds.
- García Manche?o, Olga,Kuhlmann, Jan H.,Pérez-Aguilar, María Carmen,Piekarski, Dariusz G.,Uygur, Mustafa
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supporting information
p. 3392 - 3399
(2021/05/21)
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- Core-shell Co-MOF-74@Mn-MOF-74 catalysts with Controllable shell thickness and their enhanced catalytic activity for toluene oxidation
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A series of core-shell Co-MOF-74@Mn-MOF-74 samples with different shell thicknesses were prepared by the seed growth method, which were characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), inductively coupled plasma mass spectrometry (ICP-MS), X-ray photoelectron spectroscopy, nitrogen adsorption-desorption and scanning electron microscopy (SEM). The shell thickness of these MOF samples were successfully controlled by adjusting the mass ratio between MnCl2·4H2O and Co-MOF-74. On this basis, these MOFs were applied to the catalytic oxidation of toluene. The results showed that with the growth of Mn-MOF-74 in the outer layer of Co-MOF-74, the oxidative selectivity of the substrate to benzaldehyde was greatly improved for the synergy between the core layer and shell layer. The conversion of toluene was 22.4%, and the selectivity of benzaldehyde was 98.1%. In addition, the catalyst can transform various substituted toluene into the corresponding aldehydes in highly selectivity and still keep good stability after four catalytic cycles. The selectivity of the corresponding aldehyde is generally above 80%.
- Gu, Xiangyu,Huang, Cheng,Xu, Zengchuang,Wu, Hao,Dong, Ruilan,Liu, Rui,Chen, Jing,Zhu, Hongjun
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- Ni-catalyzed non-activated C-S bond cleavage at ambient temperature for the synthesis of sulfur-containing polycyclic compounds
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A Ni-catalyzed intramolecular reaction of diarylthioether-tethered 1,8-diynes gave sulfur-containing tetracyclic compounds at ambient temperature. The transformation was initiated by non-activated sp2C-S bond cleavage along with consecutive alkyne insertions. A double intramolecular reaction of a tetrayne and an intermolecular reaction of monoynes were also available, and the corresponding polycyclic compounds were obtained. Moreover, the obtained cycloadduct showed photo-catalytic activity in benzylic oxidation.
- Akino, Mika,Ito, Mamoru,Sekine, Ayato,Shibata, Takanori
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supporting information
p. 9048 - 9051
(2021/09/14)
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- Metal-free selective reduction of acid chlorides to aldehydes using 1-hydrosilatrane
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This work uses 1-hydrosilatrane – an accessible and easy-to-handle reducing reagent – to selectively reduce acid chlorides to aldehydes. This metal-free reduction proceeds rapidly at ambient temperature in the presence of N-methylpyrrolidine, efficiently producing aldehydes in up to 54% yield and with the balance largely remaining as starting material. No over-reduced alcohol product is observed.
- Adler, Marc J.,Azam, Fawwaz,Raveenthrarajan, David
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supporting information
(2021/10/29)
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- Nano NiFe2O4 supported phenanthroline Cu(II) complex as a retrievable catalyst for selective and environmentally friendly oxidation of benzylic alcohols
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A new magnetically recoverable catalyst consisting of phenanthroline Cu(II) complex supported on nickel ferrite nanoparticles was prepared. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, transmission and scanning electron microscopes, thermogravimetry, energy dispersive X-ray spectroscopy, vibrating sample magnetometry and inductively coupled plasma. Supported copper complex used for solvent free oxidation of 1- phenyl ethanol as a model. Influence of the reaction parameters (kind of oxidant, amount of the catalyst, reaction time, solvent and reaction temperature) were studied. Because of the immobilized complex has been shown to be an efficient heterogeneous catalyst for the selective oxidation of 1-phenyl ethanol to acetophenone (94% yield) by hydrogen peroxide so this green approach extended to other benzylic alcohols. The catalyst had been reused 10 times with no significant loss of catalytic activity. SEM, EDX, XRD, and ICP analysis of reused catalyst indicated that the catalyst was stable after the reaction.
- Mehrjoyan, Forouzan,Afshari, Mozhgan
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- Copper(II)-Ethanolamine Triazine Complex on Chitosan-Functionalized Nanomaghemite for Catalytic Aerobic Oxidation of Benzylic Alcohols
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Abstract: In this study a novel, effective and recoverable Cu(II)-catalyst was synthesized by incorporating of Cu(OAc)2 within ethanolamine-triazine derivative (TAETA) attached to chitosan (Chs)-functionalized γ-Fe2O3 nanoparticles [MNP@Chs/TAETA-Cu(II)]. It was characterized by different techniques such as FT-IR, EDS, ICP, TEM, TGA and VSM. The as-prepared nanocomposite demonstrated high oxidation activity and desired selectivity in the aerobic oxidation of structurally diverse set of benzyl alcohols. Spectral results and leaching experiments revealed that this magnetically recoverable heterogeneous catalyst preserved its structure after it was reused several?times. This protocol offers some beneficial features such as the use of oxygen as an ideal oxidant, stability of nanocomplex, easily catalyst separation by using an external magnetic field and efficient recycling as well as the lack of by-products. Graphic Abstract: [Figure not available: see fulltext.]
- Hasanpour, Benyamin,Jafarpour, Maasoumeh,Feizpour, Fahimeh,Rezaeifard, Abdolreza
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- Solvent-free selective oxidation of alcohols with tert-butyl hydroperoxide catalyzed by palladium(II) isatin Schiff base complex supported into three-dimensional mesoporous silica KIT-6
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In this work, the catalytic activity of a palladium(II) isatin Schiff base complex immobilized into mesoporous silica KIT-6 (Pd-isatin Schiff base@KIT-6) was studied for the oxidation of different alcohols with tert-butyl hydroperoxide (TBHP, 70% aqueous solution) as an oxidant under solvent-free conditions. To find the suitable reaction conditions, the effect of essential factors including the solvent, temperature, catalyst amount and kind of oxidant on the oxidation of benzyl alcohol was explored. The results showed that in this catalytic system, the corresponding aldehydes and ketones were obtained with high to excellent yields at 50?°C without the formation of carboxylic acids as by-products. The catalyst was easily recovered by simple filtration and reused in five subsequent reaction cycles without any significant loss in the catalytic activity. Moreover, the comparison of the Fourier transform infrared (FT-IR) spectrum, X-ray diffraction (XRD) pattern, scanning and transmission electron microscopy (SEM and TEM) images of the used catalyst with a fresh one showed that the structure of the Pd-isatin Schiff base@KIT-6 catalyst remained intact after five times of reuse.
- Mousavi, Davoud,Ardakani, Mehdi Hatefi,Saeednia, Samira,Sabet, Mohammad
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p. 1105 - 1121
(2020/11/17)
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- A new porous Co(ii)-metal-organic framework for high sorption selectivity and affinity to CO2and efficient catalytic oxidation of benzyl alcohols to benzaldehydes
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Herein, we report a new 3D porous Co(ii)-based metal-organic framework catalyst (Me2NH2)2[Co3(L)2(H2O)2]·2DMF (MOF I), which has been successfully prepared by using Co(ii) ions and rigid V-shaped 3,5-di(2,4-dicarboxylphenyl)pyridine (H4L) via the solvothermal reaction. Structural analysis reveals that I displays a porous structure with the pore size of 16.2 × 7.2 ?2 based on the trinuclear [Co3(COO)4(H2O)2N2] secondary building units (SBUs). Gas sorption experiments on the guest free sample I′ reveals a high capacity and selectivity to CO2 over CH4. And further, the catalytic explorations of the I′-catalyzed system (I′: 3 mol%; proline: 40 mol%; CH3CN: 2 mL) reveal that benzyl alcohols with different structures can be efficiently transformed into benzyl alcohols without by-products under mild conditions.
- Wu, Yun-Long,Yang, Rong-Rong,Yang, Guo-Ping,Yan, Yang-Tian,Su, Xiao-Lei,He, Xin-Hai,Song, Yan-Yan,Ma, Zheng-Sheng,Wang, Yao-Yu
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p. 3717 - 3723
(2021/05/31)
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- An expeditious and efficient method for the oxidation of benzyl alcohols by homogeneous electrolysis
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A greener and inexpensive electrochemical method has been developed for the oxidation of benzyl alcohols by homogeneous electrolysis. The electrochemical reaction was carried out in an undivided cell equipped with carbon and stainless steel electrodes at room temperature. The homogeneous solution made up of acetonitrile/water containing substrate and ammonium bromide with a catalytic amount of H2SO4 as supporting electrolyte. The reaction condition was optimized with various electrochemical experimental parameters and evaluated with various substituted benzyl alcohols to result in excellent yield of aldehydes (>83%).
- Jagatheesan, Rathinavel,Shanmugavelan, Poovan,Sambathkumar, Subramaniyan,Ramesh, Pugalenthi
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supporting information
p. 3013 - 3022
(2021/08/12)
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- A green approach for aerobic oxidation of benzylic alcohols catalysed by CuI-Y zeolite/TEMPO in ethanol without additional additives
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An efficient and green protocol for aerobic oxidation of benzylic alcohols in ethanol using CuI-Y zeolite catalysts assisted by TEMPO (TEMPO = 2,2,6,6-tetramethyl-1-piperidine-N-oxyl) as the radical co-catalyst in the presence of atmospheric air under mild conditions is reported. The CuI-Y zeolite prepared via ion exchange between CuCl and HY zeolite was fully characterized by a variety of spectroscopic techniques including XRD, XPS, SEM, EDX and HRTEM. The incorporation of Cu(i) into the 3D-framework of the zeolite rendered the catalyst with good durability. The results of repetitive runs revealed that in the first three runs, there was hardly a decline in activity and a more substantial decrease in yield was observed afterwards, while the selectivity remained almost unchanged. The loss in activity was attributed to both the formation of CuO and the bleaching of copper into the liquid phase during the catalysis, of which the formation of CuO was believed to be the major contributor since the bleaching loss for each run was negligible (2%). In this catalytic system, except TEMPO, no other additives were needed, either a base or a ligand, which was essential in some reported catalytic systems for the oxidation of alcohols. The aerobic oxidation proceeded under mild conditions (60 °C, and 18 hours) to quantitatively and selectively convert a wide range of benzylic alcohols to corresponding aldehydes, which shows great potential in developing green and environmentally benign catalysts for aerobic oxidation of alcohols. The system demonstrated excellent tolerance against electron-withdrawing groups on the phenyl ring of the alcohols and showed sensitivity to steric hindrance of the substrates, which is due to the confinement of the pores of the zeolite in which the oxidation occurred. Based on the mechanism reported in the literature for homogenous oxidation, a mechanism was analogously proposed for the aerobic oxidation of benzylic alcohols catalysed by this Cu(i)-containing zeolite catalyst. This journal is
- Senthilkumar, Samuthirarajan,Zhong, Wei,Natarajan, Mookan,Lu, Chunxin,Xu, Binyu,Liu, Xiaoming
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p. 705 - 713
(2021/01/25)
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- Nitrosoarene-Catalyzed HFIP-Assisted Transformation of Arylmethyl Halides to Aromatic Carbonyls under Aerobic Conditions
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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.
- Pradhan, Suman,Sharma, Vishali,Chatterjee, Indranil
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supporting information
p. 6148 - 6152
(2021/08/03)
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- Dual Nickel/Photoredox-Catalyzed Deaminative Cross-Coupling of Sterically Hindered Primary Amines
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We report a method to activate α-3° amines for deaminative arylation via condensation with an electron-rich aldehyde and merge this reactivity with nickel metallaphotoredox to generate benzylic quaternary centers, a common motif in pharmaceuticals and natural products. The reaction is accelerated by added ammonium salts. Evidence is provided in support of two roles for the additive: inhibition of nickel black formation and acceleration of the overall reaction rate. We demonstrate a robust scope of amine and haloarene coupling partners and show an expedited synthesis of ALK2 inhibitors.
- Dorsheimer, Julia R.,Ashley, Melissa A.,Rovis, Tomislav
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supporting information
p. 19294 - 19299
(2021/11/23)
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- Preparation method for synthesizing aryl aldehyde compounds by reducing aryl secondary amide or aryl secondary amide derivative through phenylsilane
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The invention provides a preparation method for synthesizing aryl aldehyde compounds by reducing an aryl secondary amide or aryl secondary amide derivative through phenylsilane. In an inert atmosphere, the aryl secondary amide or an aryl secondary amide derivative is used as a raw material, phenylsilane is used as a reducing agent, 1, 4-dioxane or tetrahydrofuran or diethyl ether is used as a solvent, under the action of isopropyl magnesium chloride, a reaction is performed for 12-48 h at 40-70 DEG C, quenching, separating and purification are performed after the reaction is completed, and the aryl aldehyde product is obtained. The whole preparation process realizes one-step conversion from aryl secondary amide to aryl aldehyde, has the advantages of low cost, mild reaction conditions and high reaction yield, and avoids the use of high-temperature harsh conditions and high-cost noble metal catalysts.
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Paragraph 0037-0041
(2021/11/10)
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- Generation of Aryllithium Reagents from N -Arylpyrroles Using Lithium
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Treatment of 1-aryl-2,5-diphenylpyrroles with lithium powder in tetrahydrofuran at 0 °C results in the generation of the corresponding aryllithium reagents through reductive C-N bond cleavage.
- Ozaki, Tomoya,Kaga, Atsushi,Saito, Hayate,Yorimitsu, Hideki
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p. 3019 - 3028
(2021/06/02)
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- Aerobic oxidative C?C bond cleavage of aromatic alkenes by a high valency iron-containing perovskite catalyst
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High valency iron-containing perovskite catalyst BaFeO3-dcould efficiently promote the additive-free oxidative C?C bond cleavage of various aromatic alkenes to the corresponding aldehydes or ketones using O2as the sole oxidant. This system was applicable to the gram-scale oxidation of 1,1-diphenylethylene, in which 2.71 g (75% yield) of the analytically pure ketone could be isolated.
- Shibata, Satomi,Kamata, Keigo,Hara, Michikazu
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p. 2369 - 2373
(2021/04/22)
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- Aerobic epoxidation of styrene over Zr-based metal-organic framework encapsulated transition metal substituted phosphomolybdic acid
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Catalytic epoxidation of styrene with molecular oxygen is regarded as an eco-friendly alternative to producing industrially important chemical of styrene oxide (STO). Recent efforts have been focused on developing highly active and stable heterogeneous catalysts with high STO selectivity for the aerobic epoxidation of styrene. Herein, a series of transition metal monosubstituted heteropolyacid compounds (TM-HPAs), such as Fe, Co, Ni or Cu-monosubstituted HPA, were encapsulated in UiO-66 frameworks (denoted as TM-HPA@UiO-66) by direct solvothermal method, and their catalytic properties were investigated for the aerobic epoxidation of styrene with aldehydes as co-reductants. Among them, Co-HPA@UiO-66 showed relatively high catalytic activity, stability and epoxidation selectivity at very mild conditions (313 K, ambient pressure), that can achieve 82 % selectivity to STO under a styrene conversion of 96 % with air as oxidant and pivalaldehyde (PIA) as co-reductant. In addition, the hybrid composite catalyst can also efficiently catalyze the aerobic epoxidation of a variety of styrene derivatives. The monosubstituted Co atoms in Co-HPA@UiO-66 are the main active sites for the aerobic epoxidation of styrene with O2/PIA, which can efficiently converting styrene to the corresponding epoxide through the activation of the in-situ generated acylperoxy radical intermediate.
- Hu, Dianwen,Song, Xiaojing,Zhang, Hao,Chang, Xinyu,Zhao, Chen,Jia, Mingjun
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- C70Fullerene Catalyzed Photoinduced Aerobic Oxidation of Benzylamines to Imines and Aldehydes
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C70 fullerene catalyzed photoinduced oxidation of benzylic amines at ambient conditions has been explored here. The developed strategy's main feature includes the additive/oxidant-free conversion of benzylic amine to corresponding imine and aldehydes. The reaction manifests broad substrate scope with excellent function group leniency and is applicable up to the gram scale. Further, symmetrical secondary amines can also be synthesized from benzylic amine in a one-pot two-step process. Various experiments and density functional theory studies revealed that the current reaction involves the generation of reactive oxygen species, single electron transfer reaction, and benzyl radical formation as key steps under photocatalytic conditions.
- Kumar, Inder,Kumar, Rakesh,Gupta, Shiv Shankar,Sharma, Upendra
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supporting information
p. 6449 - 6457
(2021/05/29)
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- One-Pot Direct Oxidation of Primary Amines to Carboxylic Acids through Tandem ortho-Naphthoquinone-Catalyzed and TBHP-Promoted Oxidation Sequence
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Biomimetic oxidation of primary amines to carboxylic acids has been developed where the copper-containing amine oxidase (CuAO)-like o-NQ-catalyzed aerobic oxidation was combined with the aldehyde dehydrogenase (ALDH)-like TBHP-mediated imine oxidation protocol. Notably, the current tandem oxidation strategy provides a new mechanistic insight into the imine intermediate and the seemingly simple TBHP-mediated oxidation pathways of imines. The developed metal-free amine oxidation protocol allows the use of molecular oxygen and TBHP, safe forms of oxidant that may appeal to the industrial application.
- Kim, Hun Young,Oh, Kyungsoo,Si, Tengda
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supporting information
p. 18150 - 18155
(2021/12/09)
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- Nickel catalyzed hydrosilane reduction of (het)arenecarboxylic acids into aldehydes
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Nickel-catalyzed reduction of (het)arenecarboxylic acids with hydrosilanes in the presence of dimethyl dicarbonate as the activator affords the corresponding aldehydes. The role of the activator is the conversion of the acids into their anhydrides undergoing C–O cleavage. The good yields were achieved in case of substrates bearing electron-donating and electron-neutral groups.
- Wang, Liang,Wang, Yaoyao,Tao, Yu,Zhang, Nana,Li, Shubai
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p. 271 - 273
(2021/05/04)
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- 1,1,1,3,3,3-Hexafluoroisopropanol as an efficient medium for the room temperature oxidation of styrenes to benzaldehydes
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A room temperature N-hydroxyphthalimide-catalyzed oxidation of styrene derivatives to the corresponding aldehydes has been developed. The use of 1,1,1,3,3,3-hexafluoroisopropanol as the solvent was determined as being key for efficient oxidation. The incorporated oxygen atom originates from molecular dioxygen.
- Zhang, Zhuyong,Chen, Weidong,Luo, Junfei
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supporting information
(2020/10/23)
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- Spatially Ordered Arrangement of Multifunctional Sites at Molecule Level in a Single Catalyst for Tandem Synthesis of Cyclic Carbonates
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With fossil energy resources increasingly drying up and gradually causing serious environmental impacts, pursuing a tandem and green synthetic route for a complex and high-value-Added compound by using low-cost raw materials has attracted considerable attention. In this regard, the selective and efficient conversion of light olefins with CO2 into high-value-Added organic cyclic carbonates (OCCs) is of great significance owing to their high atom economy and absence of the isolation of intermediates. To fulfill this expectation, a multifunctional catalytic system with controllable spatial arrangement of varied catalytic sites and stable texture, in particular, within a single catalyst, is generally needed. Here, by using a stepwise electrostatic interaction strategy, imidazolium-based ILs and Au nanoparticles (NPs) were stepwise immobilized into a sulfonic group grafted MOF to construct a multifunctional single catalyst with a highly ordered arrangement of catalytic sites. The Au NPs and imidazolium cation are separately responsible for the selective epoxidation and cycloaddition reaction. The mesoporous cage within the MOF enriches the substrate molecules and provides a confined catalytic room for the tandem catalysis. More importantly, the highly ordered arrangement of the varied active sites and strong electrostatic attraction interaction result in the intimate contact and effective mass transfer between the catalytic sites, which allow for the highly efficient (>74% yield) and stable (repeatedly usage for at least 8 times) catalytic transformation. The stepwise electrostatic interaction strategy herein provides an absolutely new approach in fabricating the controllable multifunctional catalysts, especially for tandem catalysis.
- Chang, Gang-Gang,Chen, Jian,Huang, Ke-Xin,Ke, Shan-Chao,Li, Jia-Xin,Luo, Ting-Ting,Ma, Xiao-Chen,Wu, Jian,Yang, Xiao-Yu
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- Cerium(IV) Carboxylate Photocatalyst for Catalytic Radical Formation from Carboxylic Acids: Decarboxylative Oxygenation of Aliphatic Carboxylic Acids and Lactonization of Aromatic Carboxylic Acids
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We found that in situ generated cerium(IV) carboxylate generated by mixing the precursor Ce(OtBu)4 with the corresponding carboxylic acids served as efficient photocatalysts for the direct formation of carboxyl radicals from carboxylic acids under blue light-emitting diodes (blue LEDs) irradiation and air, resulting in catalytic decarboxylative oxygenation of aliphatic carboxylic acids to give C-O bond-forming products such as aldehydes and ketones. Control experiments revealed that hexanuclear Ce(IV) carboxylate clusters initially formed in the reaction mixture and the ligand-to-metal charge transfer nature of the Ce(IV) carboxylate clusters was responsible for the high catalytic performance to transform the carboxylate ligands to the carboxyl radical. In addition, the Ce(IV) carboxylate cluster catalyzed direct lactonization of 2-isopropylbenzoic acid to produce the corresponding peroxy lactone and ?3-lactone via intramolecular 1,5-hydrogen atom transfer (1,5-HAT).
- Hirosawa, Keishi,Mashima, Kazushi,Satoh, Tetsuya,Shinohara, Koichi,Shirase, Satoru,Tamaki, Sota,Tsurugi, Hayato
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supporting information
(2020/03/25)
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- Method for synthesizing 4-tert-butyl benzaldehyde
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The invention discloses a method for synthesizing 4-tert-butyl benzaldehyde and belongs to the technical field of organic synthesis. The method comprises the steps of subjecting benzaldehyde and triorthoformate to a reaction to produce benzaldehyde acetal, then, subjecting the benzaldehyde acetal and isobutene to a sealed reaction in the presence of a catalyst, and carrying out acid quenching, thereby obtaining the 4-tert-butyl benzaldehyde. According to the method, the 4-tert-butyl benzaldehyde is obtained through adopting benzaldehyde protection, then, firstly, becoming an electron donatingorientating group, and then, prompting selective localization of the isobutene by employing an appropriate catalyst; and a ratio of a 2-tert-butyl benzaldehyde isomer to the product is smaller than 1:14, and after the reaction ends up, the process is applicable to industrialized large-scale production.
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- Oxidation of alcohols using an oxoammonium salt bearing the nitrate anion
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A methodology for the oxidation of alcohols to the corresponding carbonyl compounds is reported using a sub-stoichiometric quantity of an oxoammonium salt bearing the nitrate counterion. The approach proves successful for the oxidation of a range of alcohol substrates including those bearing an oxygen atom β to the site of oxidation or an α-trifluoromethyl moiety. The mechanism of the reaction has been probed and also gives an insight into the previously reported nitric acid mediated oxidation of alcohols.
- Miller, Shelli A.,Sandoval, Arturo León,Leadbeater, Nicholas E.
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supporting information
(2019/12/25)
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- Cu(ii) vitamin C tunes photocatalytic activity of TiO2 nanoparticles for visible light-driven aerobic oxidation of benzylic alcohols
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The incorporation of Cu(OAc)2 into ascorbic acid coated TiO2 nanoparticles easily provided a new heterogeneous visible-light active titania-based photocatalyst (TiO2-AA-Cu(ii)) which was characterized by different techniques such as FT-IR, XPS, ICP-AES, TGA and TEM. A red-shift of the band-edge and a reduction of the band-gap (2.8 eV vs. 3.08 for TiO2) were demonstrated by UV-DRS and Tauc plots. The combination of the as-prepared TiO2-AA-Cu(ii) nanoparticles with TEMPO and molecular oxygen (air) afforded an active catalytic system for the selective oxidation of diverse set of benzylic alcohols under solvent-free conditions. A photoassisted pathway was confirmed for oxidation reactions evidenced by good correlation between apparent quantum yield (AQY) and diffuse reflectance spectra (DRS) of the as-prepared nanohybrid. The spectral data and recycling experiments demonstrated the structural stability of the title copper photocatalyst during oxidation reactions.
- Pourmorteza, Narges,Jafarpour, Maasoumeh,Feizpour, Fahimeh,Rezaeifard, Abdolreza
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p. 12053 - 12059
(2020/04/27)
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- Heterogeneous carbon nitride photocatalyst for C-C bond oxidative cleavage of vicinal diols in aerobic micellar medium
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A green and efficient visible-light promoted aerobic oxidative C-C bond cleavage of vicinal diols in micellar medium has been developed. This protocol used graphitic carbon nitride with nitrogen vacancies (CN620) as a metal-free recyclable photocatalyst and CTAB as surfactant in water. Control experiments and the ESR results indicated that superoxide radicals and valence band holes played an important role in the reaction. Further isotope experiments suggested both a β-scission/HAT pathway and an oxidation/hydrolysis/dehydration pathway for the reaction, which is different from previous reports. The semiconductor/micellar catalyst system can be recycled at least 10 times without a significant reduction in activity. Furthermore, this reaction could be carried out under solar light irradiation and was applicable to large-scale reactions with similar results.
- Chen, Jiayang,Chen, Shengjun,Dong, Xinyu,Hong, Mei,Ni, Bangqing,Niu, Tengfei,Zhang, Tianhao
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supporting information
p. 5042 - 5049
(2020/08/25)
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- Decarboxylative formylation of aryl halides with glyoxylic acid by palladium catalysis under oxygen
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A new free radical/palladium cooperative catalyzed formylation of aryl halides with glyoxylic acid as the formyl source under oxygen conditions has been developed. Various aromatic and heteroaromatic aldehydes were produced in medium to good yields.
- Cao, Hualiang,Pu, Weiwen,Zhang, Jie,Yan, Peijun,Zhang, Jun,Xu, Sheng
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supporting information
p. 1287 - 1290
(2020/08/21)
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- Generation of Alkyl Radical through Direct Excitation of Boracene-Based Alkylborate
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The generation of tertiary, secondary, and primary alkyl radicals has been achieved by the direct visible-light excitation of a boracene-based alkylborate. This system is based on the photophysical properties of the organoboron molecule. The protocol is applicable to decyanoalkylation, Giese addition, and nickel-catalyzed carbon-carbon bond formations such as alkyl-aryl cross-coupling or vicinal alkylarylation of alkenes, enabling the introduction of various C(sp3) fragments to organic molecules.
- Hashizume, Daisuke,Hosoya, Takamitsu,Nakamura, Kei,Ohmiya, Hirohisa,Sato, Yukiya,Sumida, Yuto
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supporting information
p. 9938 - 9943
(2020/06/27)
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- Oxidative C-S Bond Cleavage of Benzyl Thiols Enabled by Visible-Light-Mediated Silver(II) Complexes
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The oxidative cleavage reaction of the C-S bond using singlet oxygen is challenging because of its uncontrollable nature. We have developed a novel method for the singlet-oxygen-mediated selective C-S bond cleavage reaction using silver(II)-ligand complexes. Visible-light-induced silver catalysis enables the controlled oxidative cleavage of benzyl thiols to afford carbonyl compounds, such as aldehydes or ketones, which are important synthetic components.
- Hong, Boseok,Aganda, Kim Christopher C.,Lee, Anna
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supporting information
p. 4395 - 4399
(2020/06/05)
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- Rhodium-catalyzed reductive carbonylation of aryl iodides to arylaldehydes with syngas
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The reductive carbonylation of aryl iodides to aryl aldehydes possesses broad application prospects. We present an efficient and facile Rh-based catalytic system composed of the commercially available Rh salt RhCl3·3H2O, PPh3 as phosphine ligand, and Et3N as the base, for the synthesis of arylaldehydes via the reductive carbonylation of aryl iodides with CO and H2 under relatively mild conditions with a broad substrate range affording the products in good to excellent yields. Systematic investigations were carried out to study the experimental parameters. We explored the optimal ratio of Rh salt and PPh3 ligand, substrate scope, carbonyl source and hydrogen source, and the reaction mechanism. Particularly, a scaled-up experiment indicated that the catalytic method could find valuable applications in industrial productions. The low gas pressure, cheap ligand and low metal dosage could significantly improve the practicability in both chemical researches and industrial applications.
- Chen, Suqing,Liu, Zhenghui,Mu, Tiancheng,Wang, Peng,Yan, Zhenzhong,Yu, Dongkun,Zhao, Xinhui
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p. 645 - 656
(2020/05/14)
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- Mild environment-friendly oxidative debenzylation of N-benzylanilines using DMSO as an oxidant
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Oxidative debenzylation of N-benzyl aromatic amines using DMSO as a non-toxic oxidant and catalyzed by TsOH gave Nphenylimines, which were spontaneously hydrolyzed to form anilines and benzaldehydes in good yields. This reaction employs mild, metal-free conditions. The conditions are also suitable for the debenzylation of benzylphenylethers.
- Yoshinaga, Tatsuro,Iwata, Takayuki,Shindo, Mitsuru
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p. 191 - 194
(2020/02/25)
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- Visible-light mediated facile dithiane deprotection under metal free conditions
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Visible light mediated facile and selective dithiane deprotection under metal free conditions is developed. Eosin Y (1 mol%) proved to be an effective catalyst for the dithiane deprotection under the ambient photoredox conditions. The standard household compact fluorescent light source (CFL bulb) proved to be effective under open-air conditions in aqueous acetonitrile at room temperature. The protocol that exhibits a broad substrate scope and functional group tolerance has been shown to expand to a range of transformations for the electron-rich and -deficient thioacetals and thioketals. The synthetic utility of this protocol has also been demonstrated by gram-scale application.
- Dharpure, Pankaj D.,Bhowmick, Anindita,Warghude, Prakash K.,Bhat, Ramakrishna G.
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- Synthetic method of aryl aldehyde compound (by machine translation)
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The method is simple to operate, the reaction conditions are mild, raw materials and the catalyst are cheap and easily available . the reaction yield is higher, and the method is environment-friendly and green in synthesis method, is an environment-friendly synthesis method of the aromatic aldehyde compound, at room temperature, through an oxidation decarboxylation reaction, of the arylamine compounds. (by machine translation)
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Paragraph 0063-0068
(2020/04/17)
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- Visible-light-promoted oxidative decarboxylation of arylacetic acids in air: Metal-free synthesis of aldehydes and ketones at room temperature
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A metal-free photocatalytic oxidative decarboxylation reaction at room temperature was developed for the synthesis of aromatic aldehydes and ketones from the corresponding arylacetic acids. The reaction was realized under blue-light irradiation by adding 1 molpercent of 4CzIPN as photocatalyst and air as oxidant. This reaction represents a novel decarboxylation of a sp3-hybridized carboxylic acids without traditional heating, additional oxidants, and metal reagents under mild conditions.
- He, Shuaiqi,Chen, Xiaolan,Zeng, Fanlin,Lu, Peipei,Peng, Yuyu,Qu, Lingbo,Yu, Bing
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supporting information
p. 1863 - 1867
(2020/01/03)
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- The first crystallographically characterised ruthenium(vi) alkylimido porphyrin competent for aerobic epoxidation and hydrogen atom abstraction
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The syntheses of [RuVI(Por)(NAd)(O)] and [RuVI(2,6-F2-TPP)(NAd)2] have been described. [RuVI(2,6-F2-TPP)(NAd)(O)] capable of catalysing aerobic epoxidation of alkenes has been characterised by X-ray crystallography with RuNAd and RuO bond distances being 1.778(5) ? and 1.760(4) ? (∠O-Ru-NAd: 174.37(19)°), respectively. Its first reduction potential is 740 mV cathodically shifted from that of [RuVI(2,6-F2-TPP)(O)2].
- Chang, Xiao-Yong,Che, Chi-Ming,Shing, Ka-Pan,Wan, Qingyun
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supporting information
p. 4428 - 4431
(2020/05/05)
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- Selective Functionalization of Styrenes with Oxygen Using Different Electrode Materials: Olefin Cleavage and Synthesis of Tetrahydrofuran Derivatives
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Electrode materials can have a significant impact on the course of an electrolysis reaction. Of particular interest is that different electrodes can generate different products from the same substrate. The electrode-material-selective transformations of styrene derivatives with molecular oxygen are reported. Platinum electrodes afford carbonyl products via cleavage of olefins, whereas tetrahydrofuran formation is achieved with carbon electrodes. A variety of different styrenes are available for both reactions. Electrolysis allows straightforward and mild chemical conversions that are metal- and oxidant-free. Electrochemical measurements illuminate the different effects of platinum and carbon electrodes on styrenes. The key to the differing reactions is probably that the oxidation potentials of the substrates are lower (higher HOMO energy) on carbon electrodes than on platinum electrodes. The adsorption of the substrates on carbon electrodes can also promote tetrahydrofuran formation.
- Imada, Yasushi,Okada, Yohei,Noguchi, Keiichi,Chiba, Kazuhiro
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supporting information
p. 125 - 129
(2018/12/05)
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- Facile Synthesis of BiVO4 for Visible-Light-Induced C?C Bond Cleavage of Alkenes to Generate Carbonyls
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BiVO4 crystals synthesized by an ultrasonic-assisted method (Sono-BiVO4) showed improved efficiency as a heterogeneous photocatalyst under visible-light irradiation. Sono-BiVO4 was successfully used for the C?C bond cleavage of alkenes to generate carbonyl compounds. Styrene derivatives were converted into carbonyl compounds in the presence of Sono-BiVO4 under highly sustainable conditions requiring only natural sources, that is, molecular oxygen, visible light, and water at room temperature. Additionally, Sono-BiVO4 could be easily separated from the reaction mixture and reused.
- Han, Sung Su,Park, Joon Yong,Hwang, Ho Seong,Choe, Hye Rin,Nam, Ki Min,Cho, Eun Jin
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p. 3018 - 3022
(2019/05/16)
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