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acetone, etc ; heterocyclic compounds; reaction mechanisms; Show all 3 Subjects
Abstract:
... A facile synthesis of derivatives of a new heterocyclic 1H-cyclopenta[b]pyridine-4,5-dione system via coupling sterically crowded 3,5-di(tert-butyl)-6-nitro-1,2-benzoquinone with arylamines and acetone was developed. The reaction mechanism involving intramolecular 1,2-shift and intermolecular transfer of tert-butyl groups of the reaction intermediates was examined on the basis of DFT/B3LYP/6–311++ ...
acetone, etc ; catalysts; catalytic activity; phosphates; tantalum; Show all 5 Subjects
Abstract:
... We report the synthesis of a tantalum phosphate catalyst with abundant strong acid sites, which is very active for the catalytic conversion of acetone into mesitylene. Characterizations, kinetic studies, and theoretical results show a relationship between the acidic sites and catalytic performance in this reaction. ...
acetone, etc ; alkenes; biomass; diamines; glycols; nickel; sulfur; Show all 7 Subjects
Abstract:
... 5,5-Dithiospiroketals are prepared by a double radical addition of α,α′-bisxanthyl acetone to an alkene followed by ionic or thermal cleavage of the xanthate groups and acid-catalyzed ring closure. A modification employs α-chloro-α′-xanthyl acetone to give unsymmetrical derivatives. Reductive removal of the sulfur atoms with Raney nickel furnishes long-chain α,ω-diacids, diols, and diamines. Using ...
acetone, etc ; condensation reactions; enamines; enantioselectivity; hydrogen; organocatalysts; Show all 6 Subjects
Abstract:
... The evaluation of a new scaffold organocatalyst of chiral spiro (S)-1-benzylspiro[indoline-3,2′-pyrrolidin]-2-one in the enantioselective aldol condensation between isatins and acetone has been executed, and a series of chiral 3-hydroxy-3-(2-oxopropyl)-indolin-2-ones have been prepared in excellent yields (up to 97%) with good enantioselectivities (up to 82% ee). Compared with the generally used c ...
acetone, etc ; bismuth; cations; crystal structure; hydrogen; polymers; Show all 6 Subjects
Abstract:
... The title compounds were prepared by precipitation from acidic solutions of the reactants in acetone/water. Bi(S₂CNH₂)₂Cl (1) crystallizes in the non-centrosymmetric trigonal space group P3₂ with a = 8.6121(3) and c = 11.1554(4) Å, Z = 3; Bi(S₂NH₂)₂SCN (2) in P2₁/c (monoclinic) with a = 5.5600(2), b = 14.3679(5), c = 12.8665(4) Å, and β = 90.37(3)°. In the crystal structure of 1 Bi³⁺ is in a seven ...
acetone, etc ; alkynes; catalytic activity; iridium; organic chemistry; regioselectivity; Show all 6 Subjects
Abstract:
... Here we demonstrate the feasibility and efficiency of simple iridium-based catalytic systems in the synthesis of multisubstituted alkenyl boronates from internal alkynes with high selectivities. A variety of alkynes were smoothly decorated with HBpin under a mild [Ir(cod)Cl]₂/dppm/acetone condition to afford trisubstituted alkenyl boronic esters with up to >99:1 regioselectivity. The diboration re ...
acetone, etc ; bagasse; biomass; calcium oxide; catalysts; peroxidation; pyrolysis; Show all 7 Subjects
Abstract:
... Ketonization of bagasse pyrolysis gas was performed over red mud-based oxides. The maximum yield of ketones in the catalytic conversion of bagasse pyrolysis gas over original red mud was 18.66% at 420 °C. To promote the oxidability of red mud and obtain a higher yield of ketones, the effect of metal oxides (CeO₂, MnO₂, TiO₂, CaO, ZrO₂) loading and loading amount of CeO₂ on red mud on ketonization ...
Pascual Garcia-Perez; Catarina Lourenço-Lopes; Aurora Silva; Antia G. Pereira; Maria Fraga-Corral; Chao Zhao; Jianbo Xiao; Jesus Simal-Gandara; Miguel A. Prieto
acetone, etc ; algae; carotenes; coasts; ethanol; solvents; xanthophylls; Iberian Peninsula; Show all 8 Subjects
Abstract:
... Brown algae are ubiquitously distributed in the NW coastline of the Iberian Peninsula, where they stand as an underexploited resource. In this study, five solvents were applied to the extraction of pigments from nine brown algae, followed by their determination and quantification by HPLC-DAD. A total of 13 compounds were detected: Six were identified as chlorophylls, six were classified as xanthop ...
Ana Julia Velez Rueda; Guillermo Ignacio Benítez; Leandro Matías Sommese; Sebastián M. Ardanaz; Estefanía L. Borucki; Nicolas Palopoli; Luis E. Iglesias; Gustavo Parisi
acetone, etc ; blood serum; condensation reactions; evolution; humans; serum albumin; Show all 6 Subjects
Abstract:
... Promiscuous activities have been related to the capacity to catalyze reactions different from those a protein has evolved to sustain. In this work, we rethought the serum albumin's promiscuous behavior using evolutionary and structural analysis. We found that the cross aldol condensation of acetone and p-formylbenzonitrile is a promiscuous reaction conserved in humans serum albumin and in closely ...
acetone, etc ; Rosaceae; fruits; juices; molecular weight; pomace; statistical analysis; Show all 7 Subjects
Abstract:
... The paper presents the kinetics of two-step ellagitannin (ET) extraction with an aqueous acetone solution from two technological types of pomace from selected berry fruits of the Rosaceae family. ETs were identified and quantified using HPLC–MS and HPLC–DAD. The results revealed the extraction kinetics of total ETs, their high and low molecular weight fractions (≤ 1569 Da and > 1569 Da), and indiv ...
acetone, etc ; blood; hardness; models; myocardium; silicone; styrene; three-dimensional printing; Show all 8 Subjects
Abstract:
... Three dimensional models can be a valuable tool for surgeons as they develop surgical plans and medical fellows as they learn about complex cases. In particular, 3D models can play an important role in the field of cardiology, where complex congenital heart diseases occur. While many 3D printers can provide anatomically correct and detailed models, existing 3D printing materials fail to replicate ...
acetone, etc ; encapsulation; ethanol; glass; green chemistry; hydrophobicity; lignin; quartz; solvents; transmittance; Show all 10 Subjects
Abstract:
... Here, we present a practical method for whitening lignin derivatives, which is solvent-controlled encapsulation (SCE) to rearrange the chromosphere at the solvent/lignin interface. Water, ethanol, and/or acetone are mixed to adjust the polarity of the solvent, resulting in lignin nanoparticles with hydrophobic chromophores within the core. Whitening lignin derivatives are produced when the hydroxy ...
acetone, etc ; detection limit; diabetes; hot water treatment; oxidation; relative humidity; temperature; Show all 7 Subjects
Abstract:
... To improve gas sensing performance of SnO₂ sensor, a heterostructure constructed by SnO₂ and SnSe₂ is designed and synthesized via hydrothermal method and post thermal oxidation treatment. The obtained SnSe₂/SnO₂ composite nanoparticles demonstrate a special core–shell structure with SnO₂ nanograins distributed in the shell and mixed SnSe₂ and SnO₂ nanograins in the core. Owning to the promoted ch ...
acetone, etc ; Sansevieria trifasciata; air flow; biofilters; cigarettes; formaldehyde; indoor air pollution; smoke; Show all 8 Subjects
Abstract:
... Botanical biofilters can effectively remove indoor air pollution. However, to apply botanical biofilters in situ, the distance of botanical biofilter to the pollutants and airflow pattern can be important factors impacting efficiency. This study examined the removal efficiency of particulate matters (PMs) and volatile organic compounds (VOCs) from cigarette smoke, such as formaldehyde and acetone, ...
acetone, etc ; Astyanax; acetonitrile; chloroform; digestion; dimethyl sulfoxide; ethanol; ingestion; microplastics; pollution; polyethylene; Show all 11 Subjects
Abstract:
... Currently, the evidence of the ingestion of microplastics (MPs) by organisms or the accumulation in different environmental compartments has been achieved using several methodological procedures. However, its uses have not been standardized across studies. In this study, we aim to assess and validate a protocol that can be useful for optimizing the identification and quantification procedures of p ...
acetone, etc ; aqueous solutions; catalysts; catalytic activity; hydrogen; hydrogen bonding; hydrogenation; indoles; quinoline; Show all 9 Subjects
Abstract:
... Combining the advantages of homogeneous catalysis and the recyclability of heterogeneous catalysts is highly desired for sustainable catalysis but remains a challenging goal. In the current work, hydrogen-bonded organic frameworks (HOFs) that consist of cage molecules with amino groups were prepared. The HOFs with heteroatom-containing porous cavities and stable backbone confine ultrafine Ru clust ...
acetone, etc ; bismuth; decontamination; environmental science; microcystin-LR; oxidation; photocatalysis; photostability; surface area; Show all 9 Subjects
Abstract:
... There is a lack of efficient methods for removing microcystins produced by cyanobacterial blooms. Here, microsphere-like bismuth vanadate (BiVO₄-60) mesocrystals using a simple solvothermal method were prepared and applied to the photocatalytic degradation of microcystin-LR. The results show that the self-assembly of BiVO₄ mesocrystals is mainly due to the coordination between acetone and BiO⁺. Th ...
acetone, etc ; biodiesel; biomass; chloroform; hexane; methanol; microalgae; oxidative stability; temperature; ultrasonic treatment; Show all 10 Subjects
Abstract:
... This study reports the effects of polar (acetone/methanol) and non-polar (chloroform/hexane) solvents on lipid yield, fatty acids methyl esters (FAMEs) composition, and biodiesel properties of microalgae. The lipids yield extracted by hexane and chloroform (100.01 and 94.33 mg/g) were higher than by methanol and acetone (40.12 and 86.91 mg/g). The polarity of solvents also affected FAMEs compositi ...
acetone, etc ; acidity; activation energy; adsorption; carbonates; catalysts; catalytic activity; ethylene glycol; nanogold; oxidation; Show all 10 Subjects
Abstract:
... Realizing the simultaneous adsorption and activation of O₂ and reactants over supported noble metal catalysts is crucial for the oxidation of organic hydrocarbons. Herein, we report a facile one-step ethylene glycol reduction method to synthesize difunctional Au(OH)Kₓ sites, which were anchored on a hierarchical hollow MFI support and adopted for acetone decomposition. The alkali ion-associated ad ...
acetone, etc ; 1-propanol; comparative study; environmental technology; ethanol; fiber optics; surface plasmon resonance; Show all 7 Subjects
Abstract:
... A comprehensive and comparative study has been performed exploiting localized surface plasmon resonance phenomenon with the purpose of sensing volatile liquids (viz. acetone, ethanol, and propanol). Accordingly, two varying geometries, namely D-type and tapered, have been used. The response has been observed by a low-cost optical detector. With utilization of AuNPs coated probe, D-type exhibits hi ...