Tag: M.W=300-350

Kaiho, Kunio published the artcileVolcanic temperature changes modulated volatile release and climate fluctuations at the end-Triassic mass extinction, Recommanded Product: Coronene, the publication is Earth and Planetary Science Letters (2022), 117364, database is CAplus.

Emplacement of the Central Atlantic Magmatic Province (CAMP) is thought to have triggered global environmental changes and the end-Triassic mass extinction (ETE). However, the mechanisms linking volcanism and environmental change are unclear. Here we provide new insight into these linkages by measuring the abundance of both sedimentary five- to six-ring polycyclic aromatic hydrocarbons (PAHs) and mercury from strata deposited in shallow marine environments across the ETE at the GSSP Kuhjoch section in Austria and St. Audrie’s Bay section in the UK. To contextualize these data, we report results from laboratory experiments measuring the production of SO₂ and CO₂ during heating of limestone and mudstone. ETE sediments record parallel enrichments of mercury and five- to six-ring PAHs, which could have been produced by intrusive magma (mainly sills) and lava flows during the early stage of the CAMP emplacement; these data indicate a direct link between massive gas emission from sill contact metamorphism and the ETE. The fraction of coronene – a highly condensed six-ring PAH that requires greater energy to form compared to smaller PAHs – accumulated in the sediments during these initial volcanic events is low, and it coincides with the terrestrial plant turnover and initial marine extinction. Coronene increases to medium values coinciding with the final marine extinction level. Our heating experiments of typical carbonate and mudstone materials show that relatively low temperature heating (>350¡ãC) by sills releases massive amounts of SO₂ on a 100 yr time scale, whereas higher temperature heating (500-600¡ãC) forms more CO₂ on the same time scale. The combination of our end-Triassic geochem. data and laboratory results implies that low heating by sills caused SO₂-dominated gas emission to the stratosphere and low CO₂ emission, inducing global cooling that could have precipitated the mass extinction. The subsequent increase in coronene content indicates higher volcanic temperature that would have volatilized CO₂ rich gas; the consequence was a switch to greater CO₂ release and long-term (>105 yr) global warming.

Earth and Planetary Science Letters published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C24H12, Recommanded Product: Coronene.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Yu, Linhui published the artcileDisclosing the natures of carbon edges with gradient nanocarbons for electrochemical hydrogen peroxide production, Category: catalysis-chemistry, the publication is Matter (2022), 5(6), 1909-1923, database is CAplus.

Understanding the intrinsic nature of carbon edges toward the electrocatalytic reduction of O₂ to H₂O₂ is challenging due to the inevitable coexistence of edges and heteroatom groups. Herein, ten different gradient nanocarbons with well-defined edge topologies and sizes are used as models to investigate the explicit function of each common edge at a mol. level. We suggest that both armchair and zigzag configurations are pos. in H₂O₂ formation. Direct proportional structure-function relationships between the size/number/areas of edges and the activities are then proposed. Moreover, the dynamic evolution processes and kinetic behaviors of key intermediate products including O₂ (ads) and superoxide anion O₂^-* are monitored with time-resolved IR spectroscopy and simulation calculations Depending on different edge configurations, O₂ (ads) and O₂^-* species show a steep growth trend in the first 7.3 and 10 s and reach equilibrium until 10 and 13.3 s, resp. O₂ (ads) + e^– ¡ú O₂^-* as a possible rate-determining step (RDS) is evidenced by isotopic-labeling studies.

Matter published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C6H8N2, Category: catalysis-chemistry.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Veisi, Hojat published the artcileAn efficient clean methodology for the C-S coupling to aryl thioethers and S-S homocoupling to aromatic disulfides catalyzed over a Ce(IV)-leucine complex immobilized on mesoporous MCM-41, Product Details of C14H10O4S2, the publication is New Journal of Chemistry (2019), 43(26), 10343-10351, database is CAplus.

A novel Ce(IV)-anchored L-leucine covalently bonded to mesoporous MCM-41 has been synthesized by a non-hydrothermal post-functionalization approach. It has been thoroughly characterized by sophisticated physicochem. techniques. The material was applied in the efficient green synthesis of aromatic sulfides by C-S coupling using mol. sulfur and haloarenes. Another catalytic application was in the synthesis of sym. disulfides by the homocoupling of aromatic thiols in the presence of H₂O₂ as an oxidant. The ligand-free protocol is simple, clean and free from hazardous chems. Moreover, the catalyst is reusable for several times, thus making the methodol. sustainably viable.

New Journal of Chemistry published new progress about 119-80-2. 119-80-2 belongs to catalysis-chemistry, auxiliary class sulfides,Carboxylic acid,Benzene, name is 2,2′-Dithiodibenzoic acid, and the molecular formula is C10H10O2, Product Details of C14H10O4S2.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Moeini, Nazanin published the artcileAnchoring Ni (II) on Fe₃O₄@tryptophan: A recyclable, green and extremely efficient magnetic nanocatalyst for one-pot synthesis of 5-substituted 1H-tetrazoles and chemoselective oxidation of sulfides and thiols, Product Details of C14H10O4S2, the publication is Applied Organometallic Chemistry (2018), 32(9), n/a, database is CAplus.

A green, novel and extremely efficient nanocatalyst was successfully synthesized by the immobilization of Ni as a transition metal on Fe₃O₄ nanoparticles coated with tryptophan. This nanostructured material was characterized using Fourier transform IR spectroscopy, transmission electron microscopy, SEM, energy-dispersive X-ray spectroscopy, thermogravimetric anal., inductively coupled plasma optical emission spectroscopy, vibrating sample magnetometry and X-ray diffraction. The prepared nanocatalyst was applied for the oxidation of sulfides, oxidative coupling of thiols and synthesis of 5-substituted 1H-tetrazoles. The use of non-toxic, green and inexpensive materials, easy separation of magnetic nanoparticles from a reaction mixture using a magnetic field, efficient and one-pot synthesis, and high yields of products are the most important advantages of this nanocatalyst.

Applied Organometallic Chemistry published new progress about 119-80-2. 119-80-2 belongs to catalysis-chemistry, auxiliary class sulfides,Carboxylic acid,Benzene, name is 2,2′-Dithiodibenzoic acid, and the molecular formula is C14H10O4S2, Product Details of C14H10O4S2.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Molaei, Somayeh published the artcileHighly Efficient Oxidative Coupling of Thiols and Oxidation of Sulfides in the Presence of MCM-41@Tryptophan-Cd and MCM-41@Tryptophan-Hg as Novel and Recoverable Nanocatalysts, Quality Control of 119-80-2, the publication is Catalysis Letters (2018), 148(7), 1834-1847, database is CAplus.

Abstract: Two heterogeneous catalysts, MCM-41@Tryptophan-Cd and MCM-41@Tryptophan-Hg, were synthesized by immobilization of Cd or Hg complexes on MCM-41 as novel, efficient, recoverable and stable nanocatalysts for Oxidation of sulfides to sulfoxides and oxidative coupling of thiols into their corresponding disulfides. These functionalized complexes were characterized by FT-IR spectroscopy, thermogravimetric anal. (TGA), powder X-ray diffraction (XRD) and N₂ adsorption-desorption isotherms. The designed catalysts successfully oxidized a variety of sulfides and thiols with short reaction times in high to excellent yields at room temperature and recovered for several times without significant loss of their catalytic activity. Graphical Abstract: Synthesis of Cd and Hg tryptophan complexes immobilized on to surface of mesoporous MCM-41 under mild reaction conditions has been presented. After characterization of these catalysts, their catalytic activity has been investigated for the synthesis of sulfoxide and disulfides derivatives [Figure not available: see fulltext.].

Catalysis Letters published new progress about 119-80-2. 119-80-2 belongs to catalysis-chemistry, auxiliary class sulfides,Carboxylic acid,Benzene, name is 2,2′-Dithiodibenzoic acid, and the molecular formula is C14H10O4S2, Quality Control of 119-80-2.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Molaei, Somayeh published the artcileCu(II) and Cd(II) anchored functionalized mesoporous SBA-15 as novel, highly efficient and recoverable heterogeneous catalysts for green oxidative coupling of thiols and C-S cross-coupling reaction of aryl halides, Recommanded Product: 2,2′-Dithiodibenzoic acid, the publication is Polyhedron (2018), 35-47, database is CAplus.

Two novel heterogeneous catalysts have been synthesized by anchoring Cu(II) and Cd(II) creatinine complexes onto the surface of mesochannels of SBA-15 and used as catalysts for highly efficient oxidation of thiols to disulfides with hydrogen peroxide and for synthesis of sym. diaryl sulfides from aryl halides using S₈ and KOH. The structure of the prepared catalysts was determined using SEM, FT-IR, X-ray diffraction, elemental anal., N₂ adsorption-desorption anal. and TGA. The catalysts could be reused several times without appreciable loss in their activity.

Polyhedron published new progress about 119-80-2. 119-80-2 belongs to catalysis-chemistry, auxiliary class sulfides,Carboxylic acid,Benzene, name is 2,2′-Dithiodibenzoic acid, and the molecular formula is C14H10O4S2, Recommanded Product: 2,2′-Dithiodibenzoic acid.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Molaei, Somayeh published the artcileSynthesis and characterization of MCM-41@AMPD@Zn as a novel and recoverable mesostructured catalyst for oxidation of sulfur containing compounds and synthesis of 5-substituted tetrazoles, SDS of cas: 119-80-2, the publication is Microporous and Mesoporous Materials (2018), 241-250, database is CAplus.

Zinc bound to mesoporous silica MCM-41 functionalized with (3-chloropropyl)trimethoxysilane and 2-amino-2-methyl-1,3-propanediol was prepared as a recyclable catalyst for solvent-free oxidation of sulfides and thiols with H₂O₂ to form sulfides and disulfides, resp., and for the cycloaddition of NaN₃ to nitriles in PEG-400 to yield tetrazoles. The catalyst was used eight times for oxidation and cycloaddition reactions with < 10% decrease in yield over the eight reaction cycles.

Microporous and Mesoporous Materials published new progress about 119-80-2. 119-80-2 belongs to catalysis-chemistry, auxiliary class sulfides,Carboxylic acid,Benzene, name is 2,2′-Dithiodibenzoic acid, and the molecular formula is C14H10O4S2, SDS of cas: 119-80-2.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Nemati, Mohammad published the artcileImmobilization of Gd(III) complex on Fe₃O₄: A novel and recyclable catalyst for synthesis of tetrazole and S-S coupling, COA of Formula: C14H10O4S2, the publication is Polyhedron (2019), 75-84, database is CAplus.

A novel catalysts was prepared by anchoring a Gd(III) complex with OH groups on the surface of Fe₃O₄. The catalysts was characterized by FTIR, TGA, XRD, EDX, VSM, and ICP-OES techniques and tested in the synthesis of tetrazoles and S-S coupling. The catalyst has several advantages including easily recovery from the reaction mixture by magnetic field, several consecutive cycles without noticeable change in its catalytic activity, the use of green solvent, the use of aspartic acid as green ligand, chem. and phys. stability of the obtained catalyst, short reaction time and good to excellent isolated yields of all products.

Polyhedron published new progress about 119-80-2. 119-80-2 belongs to catalysis-chemistry, auxiliary class sulfides,Carboxylic acid,Benzene, name is 2,2′-Dithiodibenzoic acid, and the molecular formula is C14H10O4S2, COA of Formula: C14H10O4S2.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Khiri, Dorra published the artcileDetailed kinetic study of hydrogen abstraction reactions of triphenylene, benzo[e]pyrene, dibenzo[fg,op]naphtacene, and coronene by H atoms, Recommanded Product: Coronene, the publication is International Journal of Chemical Kinetics (2022), 54(4), 266-276, database is CAplus.

The thermochem. and dynamics of H-abstraction reactions by H atoms have been investigated for large polycyclic aromatic hydrocarbons (PAHs) including triphenylene, benzo[e]pyrene, dibenzo[fg,op]naphtacene, and coronene using high-level ab initio methods, UCCSD(T)-F12. Highly accurate ground-state potential energy surfaces were obtained and used to compute reliable kinetic data. The structures and vibrational frequencies of all species involved in these reactions have been calculated using the CAM-B3LYP/6-311++G(d,p) level of theory. The thermodn. and kinetic properties have been computed at both used levels of theories. For each type of site, the rate constants were calculated in the 500-2500 K temperature range. The results demonstrate that the overall rate constants of H-abstraction reactions from PAHs with H atoms are not sensitive to the PAHs and their structures. An overall rate constant expression for these processes regardless of the size and structure of the PAH considered is proposed: k(T) = 5.53 x 10⁷ x T^2.19exp(58.09(kJ mol^-1)/RT).

International Journal of Chemical Kinetics published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C24H12, Recommanded Product: Coronene.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Tamoradi, Taiebeh published the artcileNeodymium immobilized on Fe₃O₄: A new and recoverable catalyst for oxidation reactions and synthesis of 5-substituted 1H-tetrazoles in green condition, Synthetic Route of 119-80-2, the publication is Polyhedron (2019), 305-311, database is CAplus.

Magnetic nanoparticle functionalized with neodymium complex as catalyst and characterized by SEM, XRD, FT-IR, TGA, EDX and ICP techniques. Then, catalytic activity of prepared catalyst was examined in the synthesis of tetrezoles and oxidation reactions in which observed short reaction time and high yield in these reactions.

Polyhedron published new progress about 119-80-2. 119-80-2 belongs to catalysis-chemistry, auxiliary class sulfides,Carboxylic acid,Benzene, name is 2,2′-Dithiodibenzoic acid, and the molecular formula is C16H14O6, Synthetic Route of 119-80-2.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia