2138-22-9Relevant academic research and scientific papers
Facile synthesis of visible-light-driven Cu2O/BiVO4 composites for the photomineralization of recalcitrant pesticides
Aguilera-Ruiz,De La Garza-Galván,Zambrano-Robledo,Ballesteros-Pacheco,Vazquez-Arenas,Peral,García-Pérez
, p. 45885 - 45895 (2017)
Cu2O/BiVO4 composites with different Cu2O co-catalysts were synthesized by a simple impregnation method at 200 °C for 4 h under N2 atmosphere. The Cu2O powder was obtained through the chemical reduction of copper sulfate using different reducing reagents such as ascorbic acid, glucose or fructose. The as-synthesized samples were characterized by X-ray powder diffraction, scanning and transmission electron microscopies, UV-vis diffuse reflection absorption and electrochemical impedance spectroscopy. The photoactivities of the Cu2O/BiVO4 composites were evaluated in terms of the mineralization of 4-chlorophenol (4-CP) in aqueous solutions under visible-light irradiation. The role of experimental variables including the preparation method of the co-catalyst, catalyst concentration, and 4-chlorophenol initial concentration in the photocatalytic performance of Cu2O/BiVO4 catalysts was analyzed. Likewise, the viability to recover and reuse these photocatalysts was also tested. It was found that the complete abatement of 4-CP led to the formation of chlorocatechol (4-CC) without concomitantly involving the formation pathway of hydroquinone/p-benzoquinone, 4-CC was identified in the light of experimental evidence (UV-vis) and spectral simulation done by using time-dependent density functional theory (TD-DFT) with the polarized continuum model.
Degradation of clofibric acid in acidic aqueous medium by electro-Fenton and photoelectro-Fenton
Sires, Ignasi,Arias, Conchita,Cabot, Pere Lluis,Centellas, Francesc,Garrido, Jose Antonio,Rodriguez, Rosa Maria,Brillas, Enric
, p. 1660 - 1669 (2007)
Acidic aqueous solutions of clofibric acid (2-(4-chlorophenoxy)-2-methylpropionic acid), the bioactive metabolite of various lipid-regulating drugs, have been degraded by indirect electrooxidation methods such as electro-Fenton and photoelectro-Fenton with Fe2+ as catalyst using an undivided electrolytic cell with a Pt anode and an O2-diffusion cathode able to electrogenerate H2O2. At pH 3.0 about 80% of mineralization is achieved with the electro-Fenton method due to the efficient production of oxidant hydroxyl radical from Fenton's reaction between Fe2+ and H2O2, but stable Fe3+ complexes are formed. The photoelectro-Fenton method favors the photodecomposition of these species under UVA irradiation, reaching more than 96% of decontamination. The mineralization current efficiency increases with rising metabolite concentration up to saturation and with decreasing current density. The photoelectro-Fenton method is then viable for treating acidic wastewaters containing this pollutant. Comparative degradation by anodic oxidation (without Fe2+) yields poor decontamination. Chloride ion is released during all degradation processes. The decay kinetics of clofibric acid always follows a pseudo-first-order reaction, with a similar rate constant in electro-Fenton and photoelectro-Fenton that increases with rising current density, but decreases at greater metabolite concentration. 4-Chlorophenol, 4-chlorocatechol, 4-chlororesorcinol, hydroquinone, p-benzoquinone and 1,2,4-benzenetriol, along with carboxylic acids such as 2-hydroxyisobutyric, tartronic, maleic, fumaric, formic and oxalic, are detected as intermediates. The ultimate product is oxalic acid, which forms very stable Fe3+-oxalato complexes under electro-Fenton conditions. These complexes are efficiently photodecarboxylated in photoelectro-Fenton under the action of UVA light.
Iron-catalyzed arene C-H hydroxylation
Cheng, Lu,Wang, Huihui,Cai, Hengrui,Zhang, Jie,Gong, Xu,Han, Wei
, p. 77 - 81 (2021/10/05)
The sustainable, undirected, and selective catalytic hydroxylation of arenes remains an ongoing research challenge because of the relative inertness of aryl carbon-hydrogen bonds, the higher reactivity of the phenolic products leading to over-oxidized by-products, and the frequently insufficient regioselectivity. We report that iron coordinated by a bioinspired L-cystine-derived ligand can catalyze undirected arene carbon-hydrogen hydroxylation with hydrogen peroxide as the terminal oxidant. The reaction is distinguished by its broad substrate scope, excellent selectivity, and good yields, and it showcases compatibility with oxidation-sensitive functional groups, such as alcohols, polyphenols, aldehydes, and even a boronic acid. This method is well suited for the synthesis of polyphenols through multiple carbon-hydrogen hydroxylations, as well as the late-stage functionalization of natural products and drug molecules.
Method for hydrolyzing diarylether compound to generate aryl phenol compound
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Paragraph 0157-0161, (2021/09/29)
The invention discloses a method for hydrolyzing a diarylether compound to generate an arylphenol compound. According to the method, visible light is utilized to excite a photosensitizer for catalysis. In a reaction solvent, the raw material in the formula (1) breaks a C (sp2)-O bond under the auxiliary action of acid, and hydrolysis is performed to obtain the bimolecular aryl phenol compounds in the formula (3) and the formula (4). The method can catalyze the reaction at room temperature, is green and environment-friendly, and is easy to operate; the universality is wide, the reaction yield is relatively high, and the tolerance of functional groups is strong; the synthesis method not only can realize small-scale hydrolysis conversion of various diarylether compounds, but also can realize hydrolysis of herbicidal ether, triclosan and a lignin template substrate, and even can realize large-scale hydrolysis of triclosan and the lignin template substrate to realize gram-level degradation. A new strategy is provided for recovering phenol derivatives through lignin hydrolysis, degrading pesticides and purifying wastewater containing a degerming agent or herbicide. The method has wide application prospect and use value.
In-situ fabrication of 0D/2D NiO/Bi12O17Cl2 heterojunction towards high-efficiency degrading 2, 4-dichlorophenol and mechanism insight
Song, Ning,Li, Jiaming,Li, Chunmei,Zhou, Pengjie,Jiang, Enhui,Zhang, Xiaoxu,Liu, Chunbo,Wu, Zhichen,Zheng, Hang,Che, Guangbo,Dong, Hongjun
, (2019/10/03)
2, 4-dichlorophenol (2, 4-DCP) as a persistent pollutant is frequently detected in water environments, complete eradication of trace which in water is an important task. Hence, a 0D/2D NiO/Bi12O17Cl2 heterojunction was achieved by in-situ fabrication of NiO nanodots on Bi12O17Cl2 nanosheets, which obviously improved the physical, optical and photoelectrochemical properties. The photocatalytic degradation activity of 0D/2D NiO/Bi12O17Cl2 heterojunction was boosted dramatically, which originated from the improved transfer and separation efficiency of charge carriers owing to the formation of Z-scheme heterostructure between NiO and Bi12O17Cl2. The possible photocatalytic reaction mechanism including migration behaviors of charge carriers, generation of reactive species and degradation intermediate products were revealed in depth. This work provides the valuable experiences for designing and fabricating otherwise 0D/2D heterojunction photocatalysts in the application of environmental treating fields.
Isosteres of ester derived glucose uptake inhibitors
Bergmeier, Stephen C.,Chen, Xiaozhuo,Liu, Yi,Qian, Yanrong,Roberts, Dennis A.,Shriwas, Pratik,Wang, Liyi,Zhang, Weihe
, (2020/07/31)
Glucose transporters (GLUTs) facilitate glucose uptake and are overexpressed in most cancer cells. Inhibition of glucose transport has been shown to be an effective method to slow the growth of cancer cells both in vitro and in vivo. We have previously reported on the anticancer activity of an ester derived glucose uptake inhibitor. Due to the hydrolytic instability of the ester linkage we have prepared a series of isosteres of the ester moiety. Of all of the isosteres prepared, the amine linkage showed the most promise. Several additional analogues of the amine-linked compounds were also prepared to improve the overall activity.
Pompon Dahlia-like Cu2O/rGO Nanostructures for Visible Light Photocatalytic H2 Production and 4-Chlorophenol Degradation
Karthikeyan, Sekar,Ahmed, Kassam,Osatiashtiani, Amin,Lee, Adam F.,Wilson, Karen,Sasaki, Keiko,Coulson, Ben,Swansborough-Aston, Will,Douthwaite, Richard E.,Li, Wei
, p. 1699 - 1709 (2020/02/11)
Hierarchical Cu2O nanospheres with a Pompon Dahlia-like morphology were prepared by a one-pot synthesis employing electrostatic self-assembly. Nanocomposite analogues were also prepared in the presence of reduced graphene oxide (rGO). Photophysical properties of the hierarchical Cu2O nanospheres and Cu2O/rGO nanocomposite were determined, and their photocatalytic applications evaluated for photocatalytic 4-chlorophenol (4-CP) degradation and H2 production. Introduction of trace (2O for H2 production from 2.23 % to 3.35 %, giving an increase of evolution rate from 234 μmol.g?1.h?1 to 352 μmol.g?1.h?1 respectively. The AQE for 4-CP degradation also increases from 52 % to 59 %, with the removal efficiency reaching 95 % of 10 ppm 4-CP within 1 h. Superior performance of the hierarchical Cu2O/rGO nanocomposite is attributable to increased visible light absorption, reflected in a greater photocurrent density. Excellent catalyst photostability for >6 h continuous reaction is observed.
Anchimerically Assisted Selective Cleavage of Acid-Labile Aryl Alkyl Ethers by Aluminum Triiodide and N, N-Dimethylformamide Dimethyl Acetal
Sang, Dayong,Yue, Huaxin,Zhao, Zhengdong,Yang, Pengtao,Tian, Juan
, p. 6429 - 6440 (2020/07/14)
Aluminum triiodide is harnessed by N,N-dimethylformamide dimethyl acetal (DMF-DMA) for the selective cleavage of ethers via neighboring group participation. Various acid-labile functional groups, including carboxylate, allyl, tert-butyldimethylsilyl (TBS), and tert-butoxycarbonyl (Boc), suffer the conditions intact. The method offers an efficient approach to cleaving catechol monoalkyl ethers and to uncovering phenols from acetal-type protecting groups such as methoxymethyl (MOM), methoxyethoxymethyl (MEM), and tetrahydropyranyl (THP) chemoselectively.
Selective ether bond breaking method of aryl alkyl ether
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Paragraph 0132-0136, (2020/09/16)
The invention discloses a selective aryl alkyl ether cracking method, which comprises that aryl alkyl ether, aluminum iodide and an additive are subjected to a selective ether bond cleavage reaction in an organic solvent at a temperature of -20 DEG C to a reflux temperature to generate phenol and derivatives thereof. The method is mild in condition and simple and convenient to operate, is suitablefor cracking aryl alkyl ether containing o-hydroxyl and o-carbonyl and acetal ether, and can also be used for removing tertiary carbon hydroxyl protecting groups with higher steric hindrance, such astriphenylmethyl, tertiary butyl and the like.
Practical Cleavage of Acetals by Using an Odorless Thiol Immobilized on Silica
de Léséleuc, Mylène,Kukor, Andrew,Abbott, Shaun D.,Zacharie, Boulos
, p. 7389 - 7393 (2019/12/03)
A practical, efficient and general method was developed for the deprotection of a variety of aromatic and aliphatic acetals to their corresponding catechol or diol derivatives using thiol immobilized on silica gel. This is an application for the well-known commercial solid-supported thiol (SiliaMetS Thiol). The procedure is mild and amenable to scale-up. It does not require inert atmosphere and clean conversions were observed. This method is applicable to substituted 1,3-benzodioxole and aliphatic acetals with different functionalities. It offers the advantage of a general route with high yield, which can be undertaken at ambient temperature.
