88-99-3Relevant articles and documents
A visible light driven 3D hierarchical CoTiO3/BiOBr direct Z-scheme heterostructure with enhanced photocatalytic degradation performance
He, Shiwu,Li, Qiang,Lu, Xiaoxiao,Tian, Zhenfei,Wang, Lijie,Zhang, Jinfeng
, p. 124 - 135 (2021/12/30)
A series of novel three-dimensional (3D) CoTiO3/BiOBr (CTBB) hierarchical heterostructures were preparedviaa simple hydrothermal method. In comparison with pure CoTiO3and BiOBr, all the CTBB nanocomposites display enhanced photocatalytic performance toward dye decomposition. Particularly, CTBB-5 reveals the best photocatalytic efficiency for RhB removal with aKof 0.2030 min?1, which is about 50.75 and 3.02-fold higher than that of pure CoTiO3and BiOBr, respectively. The outstanding activity is further demonstrated by MO photodegradation. The dramatically enhanced activity can be attributed to the increased surface area and reduced recombination probability of charge carriers. Furthermore, CTBB-5 exhibits excellent stability after repetitively running four times. The h+and ˙O2?are identified as the dominating reactive species contributing to the oxidation reaction. Finally, a possible Z-scheme charge transfer mechanism is presented and analyzed in detail.
Method for treating 4-AA intermediate waste liquid
-
, (2022/03/17)
The invention belongs to the technical field of chemical synthesis, and discloses a method for treating 4-AA intermediate waste liquid. The method comprises the following three steps of: (1) heating N, N-bis (2-ethoxyl) phthalimide and a basic catalyst in an aqueous solution for reflux reaction to prepare a sodium phthalate feed liquid; (2) carrying out reduced pressure distillation on the sodium phthalate feed liquid in the step (1) to obtain ethanolamine, and preparing phthalic acid from residual residues through acid regulation; and (3) introducing ammonia gas or adding ammonia water into a reaction kettle containing the phthalic acid so as to perform heating reaction, performing cooling after the reaction is finished, adding water for washing, crystallizing, filtering and drying to obtain the phthalimide. According to the method disclosed by the invention, the byproduct hazardous wastes in the deprotection step of the enzymic method 4-AA are converted into the initial raw material of the enzymic method 4-AA, so that the hazardous wastes are turned into wealth, the raw material cost is effectively reduced, the storage, transportation and treatment expenses of the hazardous wastes are also effectively reduced, and the method has remarkable economic benefits and environmental benefits.
Negative correlations between cultivable and active-yet-uncultivable pyrene degraders explain the postponed bioaugmentation
Jiang, Bo,Chen, Yating,Xing, Yi,Lian, Luning,Shen, Yaoxin,Zhang, Baogang,Zhang, Han,Sun, Guangdong,Li, Junyi,Wang, Xinzi,Zhang, Dayi
, (2021/09/24)
Bioaugmentation is an effective approach to remediate soils contaminated by polycyclic aromatic hydrocarbons (PAHs), but suffers from unsatisfactory performance in engineering practices, which is hypothetically explained by the complicated interactions between indigenous microbes and introduced degraders. This study isolated a cultivable pyrene degrader (Sphingomonas sp. YT1005) and an active pyrene degrading consortium (Gp16, Streptomyces, Pseudonocardia, Panacagrimonas, Methylotenera and Nitrospira) by magnetic-nanoparticle mediated isolation (MMI) from soils. Pyrene biodegradation was postponed in bioaugmentation with Sphingomonas sp. YT1005, whilst increased by 30.17% by the active pyrene degrading consortium. Pyrene dioxygenase encoding genes (nidA, nidA3 and PAH-RHDα-GP) were enriched in MMI isolates and positively correlated with pyrene degradation efficiency. Pyrene degradation by Sphingomonas sp. YT1005 only followed the phthalate pathway, whereas both phthalate and salicylate pathways were observed in the active pyrene degrading consortium. The results indicated that the uncultivable pyrene degraders were suitable for bioaugmentation, rather than cultivable Sphingomonas sp. YT1005. The negative correlations between Sphingomonas sp. YT1005 and the active-yet-uncultivable pyrene degraders were the underlying mechanisms of bioaugmentation postpone in engineering practices.
Synthesis of New Dialkyl 2,2′-[Carbonyl bis (azanediyl)]dibenzoates via Curtius Rearrangement
Yassine, Hasna,Bouali, Jamila,Oumessaoud, Asmaa,Ourhzif, El Mahdi,Hamri, Salha,Hafid, Abderrafia,Khouili, Mostafa,Pujol, Maria Dolors
, p. 1971 - 1979 (2021/01/21)
The 2-(alkylcarbonyl)benzoic acids obtained by esterification of phthalic anhydride are converted into azide derivatives: alkyl 2-[(azidocarbonyl)amino]benzoates and to ureas: dialkyl 2,2′-[carbonyl bis (azanediyl)]dibenzoates. These transformations were carried out using classical Curtius rearrangement conditions in the presence of diphenylphosphoryl azide (DPPA) in a basic medium, followed by hydrolysis. Subsequently, a final condensation reaction of these urea derivatives enabled us to obtain, for the first time, the new alkyl derivatives, alkyl 2-[2,4-dioxo-1,2-dihydroquinazolin-3(4 H)-yl]benzoates. All the new compounds obtained in satisfactory yields were characterized by 1H and 13C NMR, and by X-ray crystallographic analysis.
Chemical Modifications Induced by Phthalic Anhydride, a Respiratory Sensitizer, in Reconstructed Human Epidermis: A Combined HRMAS NMR and LC-MS/MS Proteomic Approach
Khong, Minh-Thuong,Berl, Valérie,Kuhn, Lauriane,Hammann, Philippe,Lepoittevin, Jean-Pierre
, p. 2087 - 2099 (2021/08/30)
Chemical skin and respiratory allergies are becoming a major health problem. To date our knowledge on the process of protein haptenation is still limited and mainly derived from studies performed in solution using model nucleophiles. In order to better understand chemical interactions between chemical allergens and the skin, we have investigated the reactivity of phthalic anhydride 1 (PA), a chemical respiratory sensitizer, toward reconstructed human epidermis (RHE). This study was performed using a new approach combining HRMAS NMR to investigate the in situ chemical reactivity and LC-MS/MS to identify modified epidermal proteins. In RHE, the reaction of PA appeared to be quite fast and the major product formed was phthalic acid. Two amide type adducts on lysine residues were observed and after 8h of incubation, we also observed the formation of an imide type cyclized adducts with lysine. In parallel, RHE samples topically exposed to phthalic anhydride (13C)-1 were analyzed using the shotgun proteomics method. Thus, 948 different proteins were extracted and identified, 135 of which being modified by PA, i.e., 14.2% of the extracted proteome. A total of 211 amino acids were modified by PA and validated by fragmentation spectra. We thus identified 154 modified lysines, 22 modified histidines, 30 modified tyrosines, and 5 modified arginines. The rate of modified residues, as a proportion of the total number of modifiable nucleophilic residues in RHE, was rather low (1%). At the protein level, modified proteins were mainly type I and type II keratins and other proteins which are abundant in the epidermis such as protein S100A, Caspase 14, annexin A2, serpin B3, fatty-acid binding protein 5, histone H2, H3, H4, etc. However, the most modified protein, mainly on histidine residues, was filaggrin, a protein that is of low abundance (0.0266 mol %) and rich in histidine.
Cleavage of Carboxylic Esters by Aluminum and Iodine
Sang, Dayong,Yue, Huaxin,Fu, Yang,Tian, Juan
, p. 4254 - 4261 (2021/03/09)
A one-pot procedure for deprotecting carboxylic esters under nonhydrolytic conditions is described. Typical alkyl carboxylates are readily deblocked to the carboxylic acids by the action of aluminum powder and iodine in anhydrous acetonitrile. Cleavage of lactones affords the corresponding ω-iodoalkylcarboxylic acids. Aryl acetylates undergo deacetylation with the participation of the neighboring group. This method enables the selective cleavage of alkyl carboxylic esters in the presence of aryl esters.
Oxidative Degradation of Azo Dyes in Aqueous Solution by Water-Soluble Iron Porphyrin Catalyst
Saha, Tapan Kumar,Frauendorf, Holm,Meyer, Franc
, p. 2870 - 2881 (2021/07/14)
Textile and food industries produce a significant volume of effluents containing azo dyes and other pollutants. These effluents are serious environmental threats, and new methods for their treatment and for the degradation of azo dyes are thus attracting much attention. The current study deals with the oxidative degradation of azo dyes by meso-tetrakis(1-methylpyridinium-4-yl)prophyrinatoiron(III), [FeIII(tmpyp)], and meta-chloroperoxy benzoic acid (m-CPBA) in aqueous solution at room temperature. The catalytic degradation of azo dyes was investigated by using rapid-scan stopped-flow spectrophotometry as a function of solution pH, [catalyst], [m-CPBA], [dye] and [surfactants]. To obtain mechanistic insight, the reaction between [FeIII(tmpyp)] and m-CPBA was also studied in aqueous solution in absence of azo dyes. Spectral analyses and kinetic data show that [FeIII(tmpyp)] is transformed into the transient intermediate [FeIV(O)(tmpyp)].+ (a compound I analog) within 20–30 ms followed by the formation of relatively stable [FeIV(O)(tmpyp)] (a compound II analog). Batch experiments reveal that the dye degradation rate is influenced by the solution pH and the concentrations of [FeIII(tmpyp)], m-CPBA, dye, and surfactants. On the basis of the kinetic and spectroscopic data, a mechanistic scheme for the dye degradation reaction and a steady-state rate equation are proposed. The products resulting from oxidative degradation of the azo dye amaranth have been analyzed by HPLC-UV-HRMS.
Cobalt-Catalyzed Acceptorless Dehydrogenation of Alcohols to Carboxylate Salts and Hydrogen
Gunanathan, Chidambaram,Kishore, Jugal,Pattanaik, Sandip,Pradhan, Deepak Ranjan
supporting information, (2020/03/03)
The facile oxidation of alcohols to carboxylate salts and H2 is achieved using a simple and readily accessible cobalt pincer catalyst (NNNHtBuCoBr2). The reaction follows an acceptorless dehydrogenation pathway and displays good functional group tolerance. The amine-amide metal-ligand cooperation in cobalt catalyst is suggested to facilitate this transformation. The mechanistic studies indicate that in-situ-formed aldehydes react with a base through a Cannizzaro-type pathway, resulting in potassium hemiacetolate, which further undergoes catalytic dehydrogenation to provide the carboxylate salts and H2
Method for directly oxidizing benzylic C-H bond to ketone or acid
-
Paragraph 0034-0037, (2020/12/14)
The invention discloses a method for directly oxidizing benzylic C-H bonds into ketone or acid. A target product is obtained through an oxidation reaction with a compound containing benzylic C-H bondsas a substrate, trichloroisocyanuric acid as an oxidizing agent and sodium bromide and tetramethyl piperidine nitrogen oxide as catalysts. The oxidizing agent and the catalysts are cheap and easy toobtain, transport and store; the oxidative catalysis effect is good; the reaction condition is mild, the requirement and effect of harsh reaction conditions on equipment are avoided, and the method issuitable for industrial mass production. The use of a large quantity of heavy metal salts is avoided, and environmental pollution is further avoided.
A Janus-type Heterogeneous Surfactant for Adipic Acid Synthesis
Antonyuk, Sergiy,Breuninger, Paul,Ernst, Stefan,Thiel, Werner R.,Vafaeezadeh, Majid,Wilhelm, Christian
, (2020/04/08)
A highly water-dispersible heterogeneous Br?nsted acid surfactant was prepared by synthesis of a bi-functional anisotropic Janus-type material. The catalyst comprises ionic functionalities on one side and propyl-SO3H groups on the other. The novel material was investigated as a green substitute of a homogeneous acidic phase transfer catalyst (PTC). The activity of the catalyst was investigated for the aqueous-phase oxidation of cyclohexene to adipic acid with 30 % hydrogen peroxide even in a decagram-scale. It can also be used for the synthesis of some other carboxylic acid derivatives as well as diethyl phthalate.
