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aromaticcompounds, etc ; carbon dioxide; coal; combustion; energy; intermediate product; sludge; synergism; thermogravimetry; Show all 9 Subjects
Abstract:
... In this work, the behaviors of municipal sludge/coal co-combustion were investigated by experiments and ReaxFF molecular dynamic simulations. The molecular models of coal and sludge were constructed based on experimental characterization. The characteristics of the separately combustion of sludge and coal from ReaxFF MD simulations were consistent with that from thermostatic thermogravimetric expe ...
aromaticcompounds, etc ; Maillard reaction; food chemistry; fructose; furfural; glucose; heat treatment; juice quality; serine; sugarcane juice; Show all 10 Subjects
Abstract:
... As a potent aromatic compound, furfural may have adverse effects on sugarcane juice quality. In this study, simplified sugarcane juice models containing glucose, fructose and amino acids were used to explore the potential precursors and formation pathways of furfural. The changes of precursors and intermediates involved in furfural formation were quantified. The results indicated that fructose con ...
aromaticcompounds, etc ; aerosols; air pollution; air quality; alkenes; combustion; pollution control; solvents; urban areas; volatile organic compounds; China; Show all 11 Subjects
Abstract:
... Understanding the emission sources of volatile organic compounds (VOCs) is critical for air pollution mitigation. Continuous measurements of atmospheric VOCs were conducted from January to February in Hangzhou in 2021. The average measured concentration of total VOCs (TVOCs) was 38.2 ± 20.9 ppb, > 42% lower than that reported by previous studies at the urban center in Hangzhou. The VOC concentrati ...
aromaticcompounds, etc ; acetylene; air; air pollution control; alkenes; cities; evaporation; inventories; models; natural gas; oil and gas industry; ozone; solvents; China; Show all 14 Subjects
Abstract:
... Both concentrations and emissions of many air pollutants have been decreasing due to implement of control measures in China, in contrast to the fact that an increase in emissions of non-methane hydrocarbons (NMHCs) has been reported. This study employed seven years continuous NMHCs measurements and the related activities data of Shanghai, a megacity in China, to explore evolution of emissions and ...
... Herein, we report a direct amidation reaction of ferrocenyl/phenyl substituted β-chlorocinnamaldehyde in presence of a robust and chalcogen stabilized iron selenide carbonyl cluster Fe₃Se₂(CO)₉. The amidation of vinylic Cₛₚ²-Cl and amides was established and Cₛₚ²-N bond formation was obtained at strongly feasible reaction conditions. The wide substrate scope of the reaction has been investigated f ...
aromaticcompounds, etc ; light; materials science; photocatalysis; Show all 4 Subjects
Abstract:
... Dearomatization reactions provide rapid access to structurally complex three-dimensional molecules from simple aromatic compounds. Plenty of reports have demonstrated their utilities in the synthesis of natural products, medicinal chemistry, and materials science in the last decades. Recently, visible-light mediated photocatalysis has emerged as a powerful tool to promote many kinds of transformat ...
aromaticcompounds, etc ; chemical communication; cyclization reactions; Show all 3 Subjects
Abstract:
... A nickel-catalyzed reductive cyclization was developed to construct the tricyclic core embedded in linoxepin, a cyclolignan with a unique benzoxepin ring. The generated diastereodivergent acetals could be converted to the common unsaturated lactone, thus allowing a racemic synthesis of this molecule after incorporation of the remaining aromatic ring. This strategy with a late-stage installation of ...
aromaticcompounds, etc ; gold; organic chemistry; regioselectivity; Show all 4 Subjects
Abstract:
... The high reactivity of gold-vinylidene complexes, generated in situ by [1,2]-bromine shift from the corresponding 1-bromoalkynes, allows the activation of one of the strongest bonds in organic chemistry (Si–O), strategically placed at the ortho-position. In this way, the synthesis of 3-bromo-2-silylbenzofuranes is achieved in good yields. Several substituents with different electronic properties a ...
aromaticcompounds, etc ; organic chemistry; reaction mechanisms; topology; Show all 4 Subjects
Abstract:
... The past decade has witnessed remarkable success in the synthesis of curved polycyclic aromatics through Scholl reactions which enable oxidative aryl–aryl coupling even in company with the introduction of significant steric strain. These curved polycyclic aromatics are not only unique objects of structural organic chemistry in relation to the nature of aromaticity but also play an important role i ...
aromaticcompounds, etc ; electrochemistry; electrodes; imides; redox potential; Show all 5 Subjects
Abstract:
... Organic electrode materials have the typical advantages of flexibility, low cost, abundant resources, and recyclability. However, it is challenging to simultaneously optimize the specific capacity, rate capability, and cycling stability. Radicals are inevitable intermediates that critically determine the redox activity and stability during the electrochemical reaction of organic electrodes. Herein ...
aromaticcompounds, etc ; amides; boron; ethylene oxide; regioselectivity; Show all 5 Subjects
Abstract:
... A regioselective 1,2-acyl, 1,2-hydrogen migration, and intermolecular opening of secondary aryl glycidic amides catalyzed by BF₃·OEt₂ were investigated. Derived from this reaction, α-Formyl acid, α-ketoamides, or fluorohydrin derivatives could regioselective be obtained, depending on the nature of the aromatic ring substituent bearing on the oxirane ring. To demonstrate the plausible mechanism in ...
aromaticcompounds, etc ; carbon dioxide; green chemistry; solvents; Show all 4 Subjects
Abstract:
... BPh₃ catalyzed the N-methylation of secondary amines and the C-methylenation (methylene-bridge formation between aromatic rings) of N,N-dimethylanilines or 1-methylindoles in the presence of CO₂ (1 atm) and PhSiH₃ without solvent at 30–40 °C. A cascade reaction from 1-methyl-2-oxindole to 3,3′-methylenebis(1-methylindole) via 1-methylindole also proceeded. ...
aromaticcompounds, etc ; Equisetum sylvaticum; glucosides; skeleton; spectroscopy; Show all 5 Subjects
Abstract:
... Two previously undescribed megastigmane glucosides, (3S)-3-hydroxy-4-oxo-7,8-dihydro-β-ionone-3-O-β-D-glucopyranoside (1), (3S)-3-hydroxy-4-oxo-β-ionone-3-O-β-D-glucopyranoside (2), an apocarotenoid glucoside named equiseoside A (3) and an unusual aromatic compound with a glucose-fused skeleton named equiseoside B (4), together with 35 known compounds (5–39) were isolated from the aerial parts of ...
aromaticcompounds, etc ; Lewis acids; ambient temperature; chromates; Show all 4 Subjects
Abstract:
... Rearrangement of cyclopropyl methanesulfonates to allylic carbocations was employed for the construction of tetralin and chromate bicyclic cores. We found that this transformation proceeds efficiently and rapidly at room temperature in the presence of dimethylaluminium triflate serving as a non-nucleophilic Lewis acid. The reaction begins with the cyclopropanol ring-opening and follows by the Frie ...
aromaticcompounds, etc ; composite polymers; ligands; polymerization; stereospecificity; Show all 5 Subjects
Abstract:
... The effects of counteranions in the cationic polymerization of N-vinylcarbazole (NVC) and vinyl ethers were investigated to develop guidelines for stereospecific living cationic polymerization. The counteranion structure, such as the charge number, metal center, and ligand, was systematically examined using the CF₃SO₃H/onium halide/metal halide initiating system. As a result, the electronic proper ...
aromaticcompounds, etc ; catalysts; chemical bonding; drugs; green chemistry; Show all 5 Subjects
Abstract:
... The construction of a carbon–carbon bond is the most fundamental aspect of synthetic chemistry. In this study, we developed a catalyst-free SN2′ reaction of β-OTf-substituted enamides with aromatics to obtain aryl-substituted aza-1,4-dicarbonyl compounds that can be in situ transformed into aryl-imidazole, aryl-thiazole, and aryl-oxazole in one-pot operation, thus achieving C–H heteroarylation of ...
aromaticcompounds, etc ; coal; coal tar; energy; macropores; models; Show all 6 Subjects
Abstract:
... The characteristics of in situ coal tar reforming with char were investigated. Subbituminous coal was continuously fed and pyrolyzed at 1173 K in a drop-tube reactor in the presence of additional char. The ratio of the additional char to coal was varied to clarify the effect of the amount of the additional char on tar reforming. The effect of the operation pressure was also evaluated. The experime ...
aromaticcompounds, etc ; crystal structure; electrical conductivity; electronics; spectroscopy; Show all 5 Subjects
Abstract:
... Two-dimensional (2D) covalent organic frameworks (COFs) are an emerging class of promising 2D materials with high crystallinity and tunable structures. However, the low electrical conductivity impedes their applications in electronics and optoelectronics. Integrating large π-conjugated building blocks into 2D lattices to enhance efficient π-stacking and chemical doping is an effective way to impro ...
aromaticcompounds, etc ; coal tar; hydrogen; oils; process design; Show all 5 Subjects
Abstract:
... Heteroatom-containing aromatics (HACAs), such as oxygen-containing aromatics (OCAs), nitrogen-containing aromatics (NCAs), and sulfur-containing aromatics (SCAs), in high-temperature coal tar (HTCT) can be regarded as valuable chemicals. Ionic liquids (ILs)/deep eutectic solvents (DESs) play a crucial role for selectively extracting and purifying HACAs from HTCT, which can be attributed to the com ...
aromaticcompounds, etc ; aromatization; gold; organic chemistry; regioselectivity; ruthenium; Show all 6 Subjects
Abstract:
... Ene-cyclopropenes give functionalized indanes and tetralines in the presence of ruthenium dimeric catalysts. This reaction involves the cyclopropene opening by the metal catalysts with a different regioselectivity respective to gold chlorides and produces totally different products than when using semisandwich ruthenium complexes. Here, the process leads to a bridged 7-oxanorbornene-type intermedi ...