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polycyclic aromatic hydrocarbons, etc ; carbon; carbon nanotubes; catalysts; dehydrogenation; energy; geometry; nanoparticles; optical isomerism; Show all 9 Subjects
Abstract:
... The chirality controllable synthesis of single-walled carbon nanotubes (SWCNTs) by the catalytic transformation of designed large polyaromatic hydrocarbon molecules has made significant progress in recent years, but the underlying mechanism, such as the role of the catalyst, has never been revealed at the atomic level. In this study, the energy profiles of the dehydrogenation processes from the C₆ ...
chlorinated hydrocarbons, etc ; acetonitrile; gas chromatography; hydrophobicity; kapok; lipophilicity; liquids; pesticides; standard deviation; triazoles; vegetable oil; vegetables; Show all 12 Subjects
Abstract:
... In this paper, a miniaturized kapok fiber-supported liquid extraction (mini-KF-SLE) method was proposed for selective extraction of pesticide residues in vegetable oils. The natural kapok fiber was used as an inert oil support material based on its hydrophobic and lipophilic properties, and the extraction device was conveniently constructed by loading 15 mg of kapok fiber at the lower middle part ...
aromatic hydrocarbons, etc ; colorimetry; cyanides; fluorescence; fluorometry; food chemistry; food safety; human health; hydrogen sulfide; toxicity; water solubility; Show all 11 Subjects
Abstract:
... Although hydrosulfide and cyanide anions play important roles in daily life that they are available in a lot of foods. However, their excess amounts contaminate water, land, and food and cause serious problems to human health. Herein, we introduce a water-soluble macrocyclic sensor based-on Calix[4]arene (MPI-Calix[4]) with dual response sites for fluorescence recognizing cyanide (CN–) and hydroge ...
... Benzo[a]pyrene (BaP) is a polycyclic aromatic hydrocarbon (PAH) that has been found in barbecued meat products and has shown carcinogenic properties in humans. The purpose of this study was to investigate the effect of vinegar (fermented vinegars and distilled vinegar) on the generation of BaP in barbecued pork sausages. The results showed that fermented vinegars and distilled vinegar could signif ...
chlorinated hydrocarbons, etc ; arsenic; chlorofluorocarbons; energy; environmental assessment; gallium; hazardous waste; hot water treatment; ionization; mineralization; ozonosphere; solar collectors; waste treatment; Show all 13 Subjects
Abstract:
... Chlorofluorocarbons (CFCs), which possess the characteristics of high volatility and destroy ozone layer, are hardly disposed of through traditional methods. With a tightly closed reaction environment and high-temperature water medium, CFCs can react and generate inorganic Cl⁻ and F⁻ under subcritical water conditions, which is very useful to enhance leaching and enrich rare metals. Therefore, in ...
... Pesticides are a well-known family of chemicals that have contaminated water systems globally. Four common subfamilies of pesticides include organochlorines, organophosphates, pyrethroids, and carbamate insecticides which have been shown to adversely affect the human nervous system. Studies have shown a link between pesticide exposure and decreased viability, proliferation, migration, and differen ...
hydrocarbons, etc ; cycloparaphenylenes; energy; exhibitions; Show all 4 Subjects
Abstract:
... Conjugated nanohoops incorporating nonalternant hydrocarbons have altered optoelectronic properties compared to [n]cycloparaphenylenes or other purely aromatic hoops. We synthesized [n]cyclo-1,5-dibenzopentalenes (n = 4, 5), in which nonalternant dibenzo[a,e]pentalenes are connected through their pentalene units. This leads to an increase in antiaromatic character and low-lying LUMO energies. Calc ...
aromatic hydrocarbons, etc ; fluorescence; polymerization; Show all 3 Subjects
Abstract:
... Linear polymers containing pillar[5]arenes as the pendant groups were designed and synthesized via a ring-opening metathesis polymerization. Such polymers could form supramolecular brush polymers and exhibited tunable fluorescence properties based on the host–guest interactions. ...
aromatic hydrocarbons, etc ; aziridines; regioselectivity; Show all 3 Subjects
Abstract:
... Aryldiazonium ions have been proven to catalyze effective cleavage of aziridines for the installation of varied aryl groups, providing access to a variety of 2-arylphenethylamines. This highly regioselective process, which can be performed at gram-scale, enjoys operational simplicity, as well as mild and metal-free conditions. ...
... An efficient Co(II)-catalyzed cross-dehydrogenative C-O coupling strategy for the arylation of N-protected amino alcohols, including 1,2-, 1,3- and 1,4-amino alcohols, branched amino alcohols and cyclic amino alcohols with different amides derivatives has been developed, affording a wide range of corresponding aryloxyamines compounds with excellent convertibility in moderate to good yields, which ...
... Despite the fact that the rim and lateral functionalizations of pillar[n]arenes have been well explored, ortho-functionalization has rarely been realized. In this work, we report a facile method of introducing a single functionality ortho to the hydroxyl group in A1/A2-dihydroxypillar[5]arene via a Grignard addition to pillar[4]arene[1]quinone followed by a dienone–phenol rearrangement. The descri ...
... A mono-pyrene substituted thiacalix[4]arene chemosensor (TCA-Py) was successfully synthesized in satisfactory yield. Fluorescence analysis revealed that TCA-Py exhibited a high recognition selectivity toward the Al(ClO₄)₃ molecule due to the synergy between the Al³⁺ cation and ClO₄⁻ anion. This unique ability to recognise an entire inorganic molecule broadens the field of molecular recognition. ...
... Pillar[n]arenes are pillar-shaped macrocyclic compounds owing to the methylene bridges linking the para-positions of the units. Owing to their unique pillar-shaped structures, these compounds exhibit various excellent properties compared with other cyclic host molecules, such as versatile functionality using various organic synthesis techniques, substituent-dependent solubility, cavity-size-depend ...
aromatic hydrocarbons, etc ; nitrites; organic chemistry; Show all 3 Subjects
Abstract:
... To explore the reaction universality of bridge nitration, the mononitration of different p-tert-butylcalix[4]arene derivatives was executed with tert-butyl nitrite as a nitration reagent. The effects of calix[4]arene conformations, substituents on the lower rim, and reaction conditions on bridge mononitration are systematically studied. The bridge nitration of p-tert-butylcalix[4]arene derivatives ...
aromatic hydrocarbons, etc ; catalytic activity; chromium; Show all 3 Subjects
Abstract:
... The use of pinacolborane to borylate abundant vinyl triflates and unactivated aryl carboxylic esters was enabled by chromium catalysis via the selective formation of vinyl and aryl boronate esters. The competing hydrided reduction or allylic borylation proceeds sluggishly or does not occur, therefore providing a selective strategy for the incorporation of boronate into olefins and arenes. Mechanis ...
aromatic hydrocarbons, etc ; cleavage (chemistry); nitriles; Show all 3 Subjects
Abstract:
... The cleavage and functionalization of C–C bonds has emerged as a powerful tool for discovery of new transformations. Herein, we report a protocol that enables direct synthesis of nitriles via copper-catalyzed oxidative cleavage and cyanation of C–C bonds in a wide variety of multicarbon alkyl-substituted (hetero)arenes. Detailed mechanistic studies reveal that a tandem oxidative process is involve ...
aromatic hydrocarbons, etc ; macrocyclic compounds; thiols; Show all 3 Subjects
Abstract:
... We report the synthesis and dynamic covalent chemistry (DCvC) of an A1/A2-dimercapto-functionalized pillar[5]arene (Di-SH-P5). The introduction of thiol moieties into this macrocyclic host makes it an effective building block for making a dynamic combinatorial library (DCL), giving rise to a set of cyclic trimers with intriguing host–guest properties as the dominant constituents. ...
... An unprecedented Au(I)-catalyzed domino intramolecular carbonyl-alkyne cyclization/indole addition strategy has been disclosed here. This generalized strategy enables the synthesis of 3(2H)-furanone-incorporated unsymmetrical bis(indolyl)methanes with generation of a stereocenter at the furanone junction from easily accessible indole-tethered ynediones. In addition, this present protocol could als ...
... An efficient targeted and synergistic cancer photo- and chemotherapy platform was constructed from aldehyde-modified pillar[5]arene and tetra-(4-aminophenyl)porphyrin successfully. ...
aromatic hydrocarbons, etc ; amination; catalytic activity; Show all 3 Subjects
Abstract:
... The first example of an aromatic haloform reaction is reported, defining a conceptually new haloform-type approach to the metal-free functionalization of arenes. We demonstrated that heteroarenes bearing a vinylogous nitromethane system, via the stage of a trichloromethane derivative, could undergo aromatic amination to produce N-functionalized arenes in quantitative yields and without the need fo ...