Xi:Irritant;
100-83-4Relevant articles and documents
Intramolecular propargyl transfer reaction catalyzed by electrogenerated nickel complexes
Franco, Delphine,Dunach, Elisabet
, p. 2951 - 2954 (1999)
The intramolecular transfer of the propargyl group of aryl propargyl ethers to a carbonyl group can be effected by a nickel-catalyzed electrochemical reaction. Homopropargyl alcohols with 2-hydroxyphenyl substituents can be obtained, using a magnesium anode in single compartment cells.
Indium as a reducing agent: Deprotection of 4-nitrobenzyl ethers and esters
Moody, Christopher J.,Pitts, Michael R.
, p. 1575 - 1576 (1999)
Indium in aqueous ethanolic ammonium chloride is an effective method for the deprotection of 4-nitrobenzyl ethers and esters.
Oxidative deoximation to their parent carbonyl compounds with ammonium chlorochromate adsorbed on alumina
Zhang, Gui-Sheng,Yang, De-Hong,Chen, Mi-Feng,Cai, Kun
, p. 2221 - 2225 (1998)
A convenient method for the oxidative cleavage of oximes to their parent aldehydes and ketones with ammonium chlorochromate adsorbed on alumina is described.
Enantioselective precipitate of amines, amino alcohols, and amino acids via schiff base reaction in the presence of chiral ionic liquid
Wu, Datong,Cai, Pengfei,Zhao, Xiaoyong,Pan, Yuanjiang
, p. 5018 - 5021 (2017)
Two novel chiral ionic liquids are synthesized as the chiral selector. Racemates of amines, amino alcohols, and amino acids could generate enantioselective precipitate with multicomponent self-assemblies under mild conditions. The approach allows for enan
Homoallylic alcohols via a chemo-enzymatic one-pot oxidation-allylation cascade
Fuchs, Michael,Schober, Markus,Pfeffer, Jan,Kroutil, Wolfgang,Birner-Gruenberger, Ruth,Faber, Kurt
, p. 2354 - 2358 (2011)
A chemo-enzymatic one-pot, two-step transformation of (hetero)-benzylic and cinnamic alcohols to yield the elongated homoallylic sec-alcohols in water in up to 96% isolated yield has been developed. The sequence comprised an enzymatic alcohol oxidation using galactose oxidase from Fusarium sp. NRRL 2903 to furnish the corresponding aldehydes, which were subjected directly to allylation via indium(0)-mediated Barbier-type coupling with allyl bromide or by addition of allylboronic acid pinacol ester. Copyright
Solvent-free oxidation of alcohols with potassium persulphate in the presence of bronsted acidic ionic liquids
Chaskar,Bhandari,Patil,Sharma,Mayeker
, p. 366 - 370 (2009)
An efficient conversion of alcohols to aldehydes was achieved using potassium persulphate and 3-methylimidazolinium methane sulfonate. Copyright Taylor & Francis Group, LLC.
Graphene oxide as a heterogeneous reagent promoted synthesis of 2-substituted 1,3-benzazoles in water
Khalili, Dariush,Banazadeh, Ali Reza
, p. 1693 - 1706 (2015)
An efficient chemical method for the synthesis of benzimidazoles, benzothiazoles, and benzoxazoles has been developed through the condensation of various aldehydes with o-phenylenediamine, o-aminothiophenol, and o-aminophenol using graphene oxide (GO) as an oxidant in water. These benzazoles are also prepared through a one-pot oxidation/condensation tandem process by reacting alcohols with 2-amino-(thio)phenol/aniline in the presence of GO in poly(ethylene glycol) as a safe media. Moreover, this carbonaceous material could be readily separated using a simple filtration.
N-methyl piperidinium chlorochromate adsorbed on alumina: A new and selective reagent for the oxidation of benzylic alcohols to their corresponding carbonyl compounds
Tajbakhsh, Mahmood,Ghaemi, Moosa,Sarabi, Siavosh,Ghassemzadeh, Mitra,Heravi, Majid M.
, p. 1213 - 1216 (2000)
N-Methyl piperidinium chlorochromate adsorbed on alumina oxidizes a wide variety of benzylic alcohols to the corresponding carbonyl compounds.
Palladium nanoparticles supported on Fe3O4/amino acid nanocomposite: Highly active magnetic catalyst for solvent-free aerobic oxidation of alcohols
Zamani, Farzad,Hosseini, Seyed Mohsen
, p. 164 - 168 (2014)
In this paper, Fe3O4 nanoparticles were coated by a number of amino acids, e.g. cysteine, serine, glycine and β-alanine, via a simple method. Because of the surface modification of the magnetic nanoparticles with amino acid, the obtained magnetic nanocomposite is able to trap palladium nanoparticles through a strong interaction between the metal nanoparticles and the functional groups of amino acids. Among the synthesized nanocomposites, Fe3O4/cysteine-Pd exhibited the highest catalytic performance and excellent selectivity in the solvent-free aerobic oxidation of various alcohols, along with high level of reusability.
Chemoselective aryl alkyl ether cleavage by thiophenolate anion through its in situ generation in catalytic amount
Nayak, Mrinal K.,Chakraborti, Asit K.
, p. 8749 - 8752 (1997)
Catalytically in sutu generated alkali metal thiophenoxide in NMP (1-melhyl-2-pyrrolidinone) chemoselectively cleaves aryl alkyl elhers in high yields.
Preparation and characterization of P4MVPMnO4/SBA-15 as an efficient heterogeneous oxidant: An organic-inorganic hybrid polymer
Kalbasi, Roozbeh Javad,Kolahdoozan, Majid,Shahabian, Keinaz,Zamani, Farzad
, p. 1109 - 1115 (2010)
This work is concerned about the preparation and characterization of MnO4- supported poly (4-methyl vinylpyridinium)/SBA-15 which was effectively employed as a heterogeneous oxidant for oxidation of aromatic alcohols. P4MVPMnO4/SBA-15 exhibited excellent activity and selectivity under mild and solvent-less conditions.
Copper(II) nanoparticles: an efficient and reusable catalyst in green oxidation of benzyl alcohols to benzaldehydes in water
Mirsafaei, Razieh,Heravi, Majid M.,Hosseinnejad, Tayebeh,Ahmadi, Shervin
, p. 823 - 830 (2016)
Copper(II) nanoparticles immobilized onto 3-aminopropyltriethoxysilane (APTES) supported on mesoporous silica KIT-5 nanocomposite (AK) was prepared. The APTES group on KIT-5 was manipulated as a suitable coordinating agent for copper(II) and fully characterized using FT-IR, SEM, EDX, ICP, TGA, XRD and UV–visible methods. Moreover, a quantitative description for metal–ligand interactions in the APTES-KIT-5 mesoporous silica-supported copper(II) acetate complex was assessed via quantum chemistry computations. This novel transition metal supported heterogeneous surface was used as an effective catalyst in low loading for selective oxidation of differently substituted benzylic alcohols in water, using H2O2 as oxidant to give the corresponding carbonyl compounds in high to excellent yields. This heterogeneous nanocatalyst can be recovered and reused several times without any significant loss of activity. Copyright
Porphyrin-Metalation-Mediated Tuning of Photoredox Catalytic Properties in Metal-Organic Frameworks
Johnson, Jacob A.,Luo, Jian,Zhang, Xu,Chen, Yu-Sheng,Morton, Martha D.,Echeverría, Elena,Torres, Fernand E.,Zhang, Jian
, p. 5283 - 5291 (2015)
Photoredox catalytic activation of organic molecules via single-electron transfer processes has proven to be a mild and efficient synthetic methodology. However, the heavy reliance on expensive ruthenium and iridium complexes limits their applications for scale-up synthesis. To this end, photoactive metal-organic frameworks (MOFs) exhibit unique advantages as novel heterogeneous photocatalytic systems, yet their utilization toward organic transformations has been limited. Here we describe the preparation and synthetic applications of four isostructural porphyrinic MOFs, namely, UNLPF-10a, -10b, -11, and -12, which are composed of free base, InIII-, SnIVCl2-, and SnIV-porphyrin building blocks, respectively. We demonstrate that the metalation with high valent metal cations (InIII and SnIV) significantly modifies the electronic structure of porphyrin macrocycle and provides a highly oxidative photoexcited state that can undergo efficient reductive quenching processes to facilitate organic reactions. In particular, UNLPF-12 exhibits both outstanding photostability and efficient photocatalytic activities toward a range of important organic transformations including aerobic hydroxylation of arylboronic acids, amine coupling, and the Mannich reaction.
Cleavage or acetyl-de-alkylation of 4-methoxybenzyl (mpm) ethers using acetic acid
Hodgetts,Wallace
, p. 1151 - 1155 (1994)
Aryl (4-methoxyphenyl)methyl (MPM) ethers are cleaved by heating with acetic acid for a few hours at 90°C, producing the corresponding phenols and (4-methoxyphenyl)methyl acetate. Under the same conditions alkyl MPM ethers are transformed directly into the corresponding alkyl acetates.
Selective Conversion of m-Hydroxybenzyl Alcohol to m-Hydroxybenzaldehide
Oi, Ryu,Takenaka, Shinji
, p. 1115 - 1116 (1988)
Pt/C-CeCl3-Bi(SO4)3 catalyst system in aqueous methanol has been found to be effective for the selective oxygen oxidation of m-hydroxybenzyl alcohol to m-hydroxybenzaldehide.
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Meinwald,Chapman
, p. 5800,5802 (1959)
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Sharpless,K.B. et al.
, p. 2503 - 2506 (1976)
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Highly effective near-infrared activating tripleta-triplet annihilation upconversion for photoredox catalysis
Huang, Ling,Wu, Wenting,Li, Yang,Huang, Kai,Zeng, Le,Lin, Wenhai,Han, Gang
, p. 18460 - 18470 (2020)
Organic triplet-triplet annihilation upconversion (TTA-UC) materials have considerable promise in areas as broad as biology, solar energy harvesting, and photocatalysis. However, the development of highly efficient near-infrared (NIR) light activatable TTA-UC systems remains extremely challenging. In this work, we report on a method of systematically tailoring an annihilator to attain such outstanding systems. By chemical modifications of a commonly used perylene annihilator, we constructed a family of perylene derivatives that have simultaneously tailored triplet excited state energy (T1) and singlet excited state energy (S1), two key annihilator factors to determine TTAUC performance. Via this method, we were able to tune the TTAUC system from an endothermic type to an exothermic one, thus significantly elevating the upconversion performance of NIR light activatable TTA upconversion systems. In conjunction with the photosensitizer PdTNP (10 μM), the upconversion efficiency using the optimal annihilator (100 μM) identified in this study was measured to be 14.1% under the low-power density of NIR light (100 mW/cm2, 720 nm). Furthermore, using such a low concentration of perylene derivative, we demonstrated that the optimal TTA-UC pair developed in our study can act as a highly effective light wavelength up-shifter to enable NIR light to drive a photoredox catalysis that otherwise requires visible light. We found that such an NIR driven method is highly effective and can even surpass directly visible light driven photoredox catalysis. This method is important for photoredox catalysis as NIR light can penetrate much deeper in colored photoredox catalysis reaction solutions, especially when done in a large-scale manner. Furthermore, this TTA-UC mediated photoredox catalysis reaction is found to be outdoor sunlight operable. Thus, our study provides a solution to enhance NIR activatable organic upconversion and set the stage for a wide array of applications that have previously been limited by the suboptimal efficiency of the existing TTA upconversion materials.
Metal-Free Electrocatalytic Aerobic Hydroxylation of Arylboronic Acids
Luo, Jian,Hu, Bo,Sam, Alyssa,Liu, T. Leo
, p. 361 - 364 (2018)
Hydroxylation of arylboronic acids to aryl alcohols was realized by a scalable electrocatalytic method. The present electrochemical hydroxylation employs low-cost methyl viologen as an organic cathodic electrocatalyst and involves O2 as a green and sustainable reactant. The electrochemical kinetic studies shown here can be a powerful tool to gain rich mechanistic and kinetic information and thus an in-depth understanding of the electrocatalytic mechanism.
Radiation chemical oxidation of benzaldehyde, acetophenone, and benzophenone
Sharma,Mudaliar,Rao,Mohan,Mittal
, p. 8402 - 8408 (1997)
Radiation chemical reactions of ·OH, O·-, and SO4·- with benzaldehyde, acetophenone, and benzophenone have been studied using both pulse and steady-state radiolysis techniques. The observed rates for the ·OH addition (k = (2.6-8.8)×109 M-1 s-1) are higher than those found for the SO4·- reaction (k = (0.7-4.0)×109 M-1 s-1). The rate for the reaction of O·- with benzaldehyde is higher than that found for ·OH, while a reverse trend is observed in the case of the two ketones. Optical absorption spectra of the intermediate transients formed in the reactions of ·OH and SO4·- with all three compounds are similar with a peak around 370-380 nm. The absorption spectra from the O·- reaction have shown a major peak at 310 nm and are somewhat different from those obtained in the reaction of ·OH. The yields of the phenolic products formed in the reaction of ·OH with benzaldehyde and acetophenone in the presence of 0.1 mM ferricyanide corresponded to only 30% and 50% ·OH yields, respectively. Benzoic acid is a major product formed with benzaldehyde in the reaction of ·OH as well as SO4·- with G values of 2.1 and 1.3 per 100 eV, respectively. The formation of the exocyclic OH adduct is a major pathway in the reactions of ·OH (by addition) and of SO4·- from hydrolysis of the initially formed radical cation (k = 2.4×104 s-1) with benzaldehyde. The exocyclic OH adduct undergoes disproportionation to give benzoic acid. The formation of the exocyclic OH adduct of acetophenone is possibly hindered owing to the bulky COCH3 group.
Decarboxylative Hydroxylation of Benzoic Acids
Ritter, Tobias,Su, Wanqi,Xu, Peng
supporting information, p. 24012 - 24017 (2021/10/06)
Herein, we report the first decarboxylative hydroxylation to synthesize phenols from benzoic acids at 35 °C via photoinduced ligand-to-metal charge transfer (LMCT)-enabled radical decarboxylative carbometalation. The aromatic decarboxylative hydroxylation is synthetically promising due to its mild conditions, broad substrate scope, and late-stage applications.
Application of Electron-Rich Covalent Organic Frameworks COF-JLU25 for Photocatalytic Aerobic Oxidative Hydroxylation of Arylboronic Acids to Phenols
Xiao, Guangjun,Li, Wenqian,Chen, Tao,Hu, Wei-Bo,Yang, Hui,Liu, Yahu A.,Wen, Ke
supporting information, p. 3986 - 3991 (2021/03/29)
Visible-light-driven organic reactions are environmentally friendly green chemical transformations among which photosynthetic oxidative hydroxylation of arylboronic acids to phenols has attracted increasing research interest during the very recent years. Given the efficiency and reusability of heterogeneous catalysts, COF-JLU25, an electron-rich COF-based photocatalyst constructed by integrating electron-donating blocks 1,3,6,8-tetrakis(4-aminophenyl)pyrene (PyTA) and 4-[4-(4-formylmethyl)-2,5-dimethoxyphenyl] benzaldehyde (TpDA), was selected as a photocatalyst for the oxidative hydroxylation of arylboronic acids. In our studies, COF-JLU25 demonstrated excellent photocatalytic activity with high efficiency, robust reusability, and low catalyst loading, showcasing an application potential of previously underexplored COF-based photocatalyst composed solely of electron-rich units.
