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phenol, etc ; carbon nanotubes; nitrogen; oxidation; species identification; Show all 5 Subjects
Abstract:
... The structural defects and heteroatom dopants of carbonaceous materials play critical roles in their activation of peroxymonosulfate (PMS) for organic pollutants’ removal. This study uses plasma-etching technology to control the levels of structural defects and nitrogen species in nitrogen-doped carbon nanotubes (N-CNTs) for excellent PMS activation. The vacancy defects, CO, pyrrolic N and graphit ...
phenol, etc ; electrodes; ligands; light; liquid-solid interface; nickel; oxidation; perchlorates; photocatalysis; China; Show all 10 Subjects
Abstract:
... Nickel (hydr)oxide (NiOH) is known to be good co-catalyst for the photoelectrochemical oxidation of water, and for the photocatalytic oxidation of organics on different semiconductors. Herein we report a greatly improved activity of Bi₂MoO₆ (BMO) by nickel hexammine perchlorate (NiNH). Under visible light, phenol oxidation on BMO was slow. After NiNH, NiOH, and Ni²⁺ loading, a maximum rate of phen ...
phenol, etc ; 2,4-D; carbon; catalysts; catalytic activity; electric energy consumption; electron paramagnetic resonance spectroscopy; hydroxyl radicals; mineralization; oxidation; reaction kinetics; sulfamethazine; China; Show all 13 Subjects
Abstract:
... An ultra-efficient electro-Fenton catalyst with porous carbon coated Fe-Mo metal (FeMo@PC), was prepared by calcining MIL-53(Fe)@MoO₃. This FeMo@PC-2 exhibited impressive catalytic performance for sulfamethazine (SMT) degradation with a high turnover frequency value (7.89 L/(g·min)), much better than most of reported catalysts. The mineralization current efficiency and electric energy consumption ...
phenol, etc ; X-ray diffraction; X-ray photoelectron spectroscopy; chemical oxygen demand; crystal structure; electrochemistry; electrodes; energy; mass spectrometry; nanotubes; oxidation; pH; surface area; wastewater treatment; China; Show all 15 Subjects
Abstract:
... In this study, we fabricated a blue-TiO₂/PbO₂-carbon nanotube (CNT) electrode in which blue TiO₂ nanotube arrays (blue-TNA) served as the substrate for PbO₂-CNT eletrodeposition. Scanning electron microscope (SEM) showed compact surface structure of the electrode. The β-PbO₂ crystal structure was detected by X-ray diffraction (XRD). The distribution of Pb, O, C, and Na elements on the electrode su ...
... The composite pollution by Cr(VI) and p-chlorophenol (4-CP) has high toxicity and harms water safety. However, research on the effective removal of Cr(VI) and 4-CP composite-polluted wastewater (C&P) and efficient synchronous electricity generation with reclaimed resources is limited. In this study, a downflow Leersia hexandra constructed wetland-microbial fuel cell (DLCW-MFC) was builded to treat ...
... Considerable interest has been focusing on the activation of peroxydisulfate (PDS) by layered double hydroxide (LDH) for degradation of organic pollutants. However, understanding the structure and chemistry of LDH by which the activation of PDS could achieve a high degradation efficiency of organic compounds is an unsolved and fundamental question in advanced oxidation processes (AOPs), and one wh ...
... An efficient method for the synthesis of trifluoroethylated benzofurans from trifluoromethyl propynols with general phenols was developed. In the presence of AgNTf₂, a variety of trifluoromethyl propynols underwent cascade Friedel-Crafts propargylation/Michael-type addition/1,3-H shift reactions with various phenols successfully to afford the corresponding trifluoroethylated benzofuran in moderate ...
... A simple, efficient, and smooth thiocyanation of indoles, phenols and aniline derivatives using NH₄SCN, DMSO and H₂SO₄ in DMF is introduced. Using this procedure, diverse indoles and N-alkyl indoles are selectively thiocyanated at the C-3 position. para-free anilines, N-alkyl anilines and phenols undergo thiocyanation at the para position selectively. ...
... Molecular photodynamics can be dramatically affected at the water/air interface. Probing such dynamics is challenging, with product formation often probed indirectly through its interaction with interfacial water molecules using time-resolved and phase-sensitive vibrational sum-frequency generation (SFG). Here, the photoproduct formation of the phenolate anion at the water/air interface is probed ...
... A novel route has been reported for C–H hydroxylation of benzyl compounds directed by a 3,4,5-tribromopyrazole auxiliary via boronation/oxidation using BBr₃ and NaBO₃·4H₂O. The strategy exhibits outstanding site selectivity and affords the corresponding phenols in moderate to excellent yields under metal-free conditions. Besides, this protocol can be achieved in one pot, which is highly promising ...
phenol, etc ; nanocatalysts; photocatalysis; photolysis; Show all 4 Subjects
Abstract:
... Nowadays, organic pollutants create severe problems worldwide. Phenolic compounds are the harmful pollutants that are developed from industrial effluents, thus causing several environmental problems. Low-cost materials show good potential capabilities for removal of phenolic compounds but are not so effective, so modification is required. New generation nanocatalysts are thought to be excellent fo ...
phenol, etc ; alkylation; photochemistry; regioselectivity; Show all 4 Subjects
Abstract:
... A mild light-driven protocol for the direct alkylation of phenols is reported. The process is driven by the photochemical activity of a halogen-bonded complex formed upon complexation of the in situ generated electron-rich phenolate anion with the α-iodosulfone. The reaction proceeds rapidly (10 min) under microfluidic conditions, delivering a wide variety of ortho-alkylated products (27 examples, ...
phenol, etc ; alkynes; regioselectivity; stereoselectivity; Show all 4 Subjects
Abstract:
... A highly efficient visible light-induced regioselective and stereoselective oxysulfonylation of alkynes with arylsulfonate phenol esters has been developed. This photocatalyst- and metal-free method proceeds smoothly under very mild conditions and exhibits a broad substrate scope, providing (E)-β-phenoxy vinylsulfones in moderate to excellent yields. Mechanistic studies indicated the involvement o ...
... The proton-coupled electron transfer (PCET) reaction has drawn extensive attention for its widespread occurrence in chemistry, biology, and materials science. The mechanistic studies via model systems such as tyrosine and phenol oxidation have gradually deepened the understanding of PCET reactions, which was widely accepted and applied to bond activation and transformation. However, direct PCET ac ...
phenol, etc ; chemical reactions; enantioselectivity; methanol; Show all 4 Subjects
Abstract:
... Intermolecular enantioselective oxidative para-dearomatization of phenols with the addition of methanol, catalyzed by a chiral 2-iodoresorcinol/lactamide, has been developed. The reaction allows for the synthesis of a broad range of 4-methoxy-2,5-cyclohexadienone products with up to 62% ee (from 2,4-disubstituted phenols in 43–62% ee; from a 3,4-disubstituted phenol in 17% ee; from 4-substituted-1 ...
phenol, etc ; biophysics; fluorescence; indoles; peptides; Show all 5 Subjects
Abstract:
... The quantum efficiency of fluorescence was measured for simple derivatives of indole and phenol and for tryptophyl and tyrosyl residues in peptides and proteins. Fluorescence of these compounds decreased as the electronegativity of substituents increased. In proteins, one strongly electronegative structure is the peptide bond. It is proposed that the observed, low fluorescence of tryptophyl and ty ...
phenol, etc ; industrial wastewater; nitrates; photocatalysts; Show all 4 Subjects
Abstract:
... The composite of α-Fe₂O₃/PTCDI based on supramolecular photocatalyst of perylene bisimide (PTCDI) decorated with α-Fe₂O₃ was prepared via calcination of ferric nitrate with self-assembly PTCDI. The composite displayed an enhanced performance for the degradation of phenol pollutants and coking wastewater via photo-Fenton reaction relative to the single component, which owing to efficient charge tra ...
... Aryl perfluorocyclopropyl ethers have been synthesized for the first time by [2 + 1] cyclopropanation between aryl trifluorovinyl ethers and a commercially available TMSCF₂Br reagent. This cycloaddition reaction between two fluorine-containing reactants proceeds smoothly in toluene at 120 °C in the presence of a catalytic amount of n-Bu₄NBr, and the reaction tolerates a variety of functional group ...
phenol, etc ; carbohydrates; ethylene oxide; glycols; regioselectivity; Show all 5 Subjects
Abstract:
... Methyl α(and β)-D-3,4-anhydro-tagatofuranosides are important synthetic building blocks as they undergo regioselective ring-opening to afford exclusively products with the D-fructo configuration. Previous attempts to prepare these compounds from the corresponding methyl D-fructofuranosides under standard Mitsunobu conditions have led to an undesired 9:1 mixture of tagato and psico oxiranes. We now ...
... High reactivity of trimethoxyphenyl (TMP)-iodonium(III) acetate for phenol O-arylation was achieved. It was first determined that the TMP ligand and acetate anion cooperatively enhance the electrophilic reactivity toward phenol oxygen atoms. The proposed method provides access to various diaryl ethers in significantly higher yields than the previously reported techniques. Various functional groups ...