Article
Chemistry, Multidisciplinary
Kevin Turke, Rafael Meinusch, Pascal Cop, Eric Prates da Costa, Raoul D. Brand, Anja Henss, Peter R. Schreiner, Bernd M. Smarsly
Summary: Functionalized porous silica monoliths with APTMS showed high catalytic activity in Knoevenagel condensation under continuous-flow conditions, with high conversion rates and tight connections between carrier material and PEEK ensuring efficiency. By connecting two monoliths, high conversions could be maintained for several flow rates.
Article
Chemistry, Multidisciplinary
Jinzhao Ji, Jinying Yuan, Yen Wei
Summary: This study demonstrates the use of customized aggregation-induced emission luminogens for visualizing heterogeneous catalytic organic reactions and enabling catalyst screening. The retro-Diels-Alder reaction was used as a model reaction, with montmorillonite K10 identified as the best catalyst through screening.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Johannes Gramueller, Philipp Dullinger, Dominik Horinek, Ruth M. Gschwind
Summary: This study elucidated the spatial structure and hydrogen bonding of BINOL derived chiral phosphoric acids (CPAs) and N-(ortho-hydroxyaryl) imines through experimental and computational methods. It experimentally validated the bidentate binding of catalyst and substrate via two hydrogen bonds. By adjusting steric repulsion and noncovalent interactions, rigid and well-defined CPA/imine monomers could be obtained. The structure of the complex, revealed by NOESY studies and theoretical calculations, pointed out the origin of the stereoselectivity for downstream transformations.
Article
Chemistry, Organic
Wagner Eduardo Richter
Summary: This article discusses the debate on the enhanced Diels-Alder reactivity of tropone derivatives by reversing the carbonyl polarity through umpolung. Results show that lower reaction barriers are related to antiaromaticity and asynchronicity. The article provides a detailed analysis of the energy variation of atoms and bonds using IQA and QTAIM.
JOURNAL OF PHYSICAL ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Tashika Agarwal, Sandeep Kaur-Ghumaan
Summary: Diiron bis(monothiolato)-bridged hydrogenase mimics and their phosphine derivatives were synthesized and investigated for electrocatalytic proton reduction activity in CH3CN-H2O. The electron-donating ability of the phosphines followed the order: dppv>PCy3>PPh3. The catalytic reduction potential shifted towards positive potentials on changing the solvent from pure CH3CN to CH3CN-H2O. An increase in the percentage of water in CH3CN led to the decomposition of certain complexes. No improvement in electrocatalytic currents was observed for certain complexes in CH3CN-H2O.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Electrochemistry
Rana Deeba, Sylvie Chardon-Noblat, Cyrille Costentin
Summary: This study investigates the competition between reduction of the substrate and deactivation of the catalyst in molecular catalysis of electrochemical reactions. A formal kinetic analysis in cyclic voltammetry framework is provided, showing that the response is governed by two parameters and the competition is independent of the scan rate. The study offers insights into the mechanism of protonation of 4-cyanopyridine radical anion.
Article
Chemistry, Organic
Yingling Nong, Chen Pang, Kunpeng Teng, Sheng Zhang, Qian Liu
Summary: An N-heterocyclic carbene (NHC)-catalyzed chemoselective activation reaction of 1-cyclopropylcarbaldehydes and a-alkynyl enals is reported. The reaction proceeds via NHC catalysis of 1-cyclopropylaldehydes, followed by a [2 + 4] cycloaddition reaction with a-alkynyl enals. Dihydropyranone derivatives with different substituents and substitution patterns are obtained in good to excellent yields with excellent enantio- and diastereoselectivities under mild conditions.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
J. J. Rushmittha, S. Radhika, C. M. Padma
Summary: A new nanocomposite of zirconium oxide supported copper ferrite (ZCFO) at different concentrations was synthesized using the co-precipitation technique. The XRD technique revealed a grain size of 60-70 nm for the sample. VSM analysis confirmed the ferromagnetic behavior of the NCs with a multi-domain nature. CV analysis showed that the synthesized sample exhibited a maximum specific capacitance of 790.87 F/g at a scan rate of 10 mV/s for ZCFO-1. GCD analysis demonstrated faradic behavior with prolonged discharge time even at higher current density, and cyclic stability analysis revealed a capacitive retention of 90.4% for ZCFO-1 over 2000 charge-discharge cycles.
INORGANIC CHEMISTRY COMMUNICATIONS
(2023)
Article
Biotechnology & Applied Microbiology
Rituparna Saha, Mainak Mukhopadhyay
Summary: This study focused on electrochemical investigation of catechol in the presence of the enzyme laccase, revealing the important impact of ABTS' electroactivity on its polymerization and the accelerated rate when combined with the laccase-mediator system.
ENZYME AND MICROBIAL TECHNOLOGY
(2022)
Article
Environmental Sciences
Aziz Aynaou, Boubaker Youbi, Youssef Lghazi, Mohammed Ait Himi, Chaimaa El Haimer, Jihane Bahar, Ahmed Sahlaoui, Itto Bimaghra
Summary: In this study, polyaniline films were fabricated on ITO substrates using different electrolytes. The effect of the counter ion on the electrochemical energy storage performances of polyaniline in supercapacitors was investigated. The specific capacitance was found to have a clear dependence on the counter ion.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Electrochemistry
Encarnacion Torralba, Eduardo Laborda, Angela Molina, Christine Cachet-Vivier, Stephane Bastide
Summary: Cavity microelectrodes (CMEs) provide a valuable platform for evaluating the electrocatalytic performance of micro- and nanoparticulate materials; experiments show capacitive distortion increases with powder surface area, but faradaic response mainly occurs on the first layer of the powder load, cyclic voltammetry and square wave voltammetry (SWV) are suitable for discriminating faradaic processes at CMEs.
Article
Chemistry, Multidisciplinary
Xinghui Zhang, Haixiong Shi, Caihong Ji, Jianyi Wang, Liping Jiang
Summary: The study focuses on the DFT calculation of the rational mechanism and catalytic activity of the gold(i)-catalyzed isotetradehydro-Diels-Alder cycloaddition of cyanamides and enamides to substituted 2,6-diaminopyridines. The results show that the produced 2,6-diaminopyridines have lower activation energy and higher reactivity, with electron-withdrawing substituents aiding the reaction. This provides important insights into the mechanism of such reactions.
Article
Chemistry, Multidisciplinary
Aditya Kulkarni, Selvakumar Arumugam, Maria Francis, Pulikanti Guruprasad Reddy, Ekta Nag, Sai Manoj N. V. T. Gorantla, Kartik Chandra Mondal, Sudipta Roy
Summary: Cyclic alkyl(amino) carbene (cAAC)-supported, structurally diverse alkali metal-phosphinidenides have been synthesized and characterized through NMR studies and X-ray diffraction. The mechanism of electron transfer process was supported by cyclic voltammetry studies and Density Functional Theory calculations. The solid state oligomerization process was found to be largely dependent on the ionic radii of alkali metal ions, steric bulk of cAAC ligands, and solvation/de-solvation/recombination of the dimeric unit.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Anni Yu, Ruben Rizo, Francisco J. Vidal-Iglesias, Rosa M. Aran-Ais, Yan-Xia Chen, Enrique Herrero, Juan M. Feliu
Summary: Information on the chemical adsorption and surface oxidation of Ru under electrochemical conditions is crucial for understanding the structure-activity relationship in Ru-based materials. This study investigates the adsorption of hydrogen and oxygen species on quasi-single-crystalline Ru films on Pt(111) electrodes. The formation of Ru-O and the conversion to RuO2 were observed at specific potentials. These findings provide insights into the electrochemical properties and ligand effects of Ru.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2022)
Article
Energy & Fuels
Dulce M. Morales, Marcel Risch
Summary: The paper introduces a seven-step method to reliably determine double layer capacitance using scan rate-dependent cyclic voltammetry, and applies it to two different systems for validation. Results show that neglecting any step leads to significant deviations in the results, and suggests a more suitable regression model for determining double layer capacitance.
JOURNAL OF PHYSICS-ENERGY
(2021)
Article
Chemistry, Multidisciplinary
Shohei Yamashita, Tatsuya Sudo, Hidehiro Kamiya, Yohei Okada
Summary: This study is important for understanding the effects of surface ligands on the colloidal stability of nanoparticles and proposes a method that can be applied to various surface ligands to maximize the colloidal stability of nanoparticles.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Applied
Kazumi Ninomiya, Shigenobu Ina, Hanae Nakamura, Yusuke Yamaguchi, Hitomi Kumagai, Hitoshi Kumagai
Summary: A model describing the rate of glucose diffusion through a dialysis membrane was developed and the adsorption of glucose on different fibers was evaluated. The adsorbed glucose increased linearly with increasing glucose concentration, and the decrease in diffusion rate was caused by the presence of water-soluble dietary fiber.
FOOD HYDROCOLLOIDS
(2022)
Article
Energy & Fuels
Genki Horiguchi, Masahiro Ito, Atsuki Ito, Hidehiro Kamiya, Yohei Okada
Summary: This study investigates the use of nanoparticles as additives to control the adhesiveness of ash particles at high temperatures, with a focus on synthetic ashes and ash samples derived from sewage sludge incineration. The results demonstrate the potential for reducing adhesiveness through chemical effects and increased porosity, highlighting the importance of understanding the role of different nanoparticles in energy recovery during combustion.
Article
Food Science & Technology
Kazumi Ninomiya, Yusuke Yamaguchi, Fumie Shinmachi, Hitoshi Kumagai, Hitomi Kumagai
Summary: This study aims to evaluate the suppressive effect of buckwheat-albumin hydrolysate on postprandial hyperglycemia and identify the responsible peptide. The results show that buckwheat-albumin hydrolysate significantly suppresses the elevation of blood glucose level after meals. A peptide with amy-lase inhibitory activity was purified from the hydrolysate and its amino acid sequence was identified. The novel amy-lase inhibitor in buckwheat albumin is proposed as a potential functional food material to suppress postprandial blood glucose elevation.
FOOD SCIENCE AND HUMAN WELLNESS
(2022)
Article
Chemistry, Organic
Kaii Nakayama, Hidehiro Kamiya, Yohei Okada
Summary: TiO2 photoelectrochemical and electrochemical radical cation Diels-Alder reactions can construct spiro ring systems. Arylidene cyclobutanes are more effective in the reaction than other cycloalkanes, possibly through a radical cation chain pathway.
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Editorial Material
Chemistry, Multidisciplinary
Shohei Yamashita, Tatsuya Sudo, Hidehiro Kamiya, Yohei Okada
Summary: This study investigates the effects of ligand length and solution temperature on colloidal stability, and demonstrates a robust ligand-exchange process. The results show that under specific conditions, a certain type of ligand can provide better colloidal stability than others, and there is kinetic hysteresis in the dispersion/agglomeration transition.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Organic
Haruka Morizumi, Kazuhiro Okamoto, Shinnosuke Akahane, Hitoshi Takemae, Mami Oba, Yohei Okada, Yoshikazu Kitano, Tetsuya Mizutani, Kazuhiro Chiba
Summary: In this study, we report a practical method for de novo preparation of imino-d-ribitol and C-azanucleosides. Diastereopure Imino-d-ribitol was synthesized on a multigram scale using simple manipulation. The efficient synthesis of corresponding C-azanucleosides with high beta-selectivity was achieved through late-stage anomeric derivatization by regio- and diastereoselective electrochemical C(sp(3))-H activation.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Aina Tanikawa, Takaya Fujihara, Natsumi Nakajima, Yuka Maeda, Yasuyuki Nogata, Erina Yoshimura, Yohei Okada, Kazuhiro Chiba, Yoshikazu Kitano
Summary: This study synthesized 15 isothiocyanates derived from beta-citronellol and evaluated their antifouling activities and toxicities. The synthesized isothiocyanates demonstrated effective antifouling properties with low toxicity, making them potential candidates for further development.
CHEMISTRY & BIODIVERSITY
(2023)
Article
Chemistry, Multidisciplinary
Tatsuya Sudo, Shohei Yamashita, Natsumi Koike, Hidehiro Kamiya, Yohei Okada
Summary: Nanoparticles are prone to aggregation, making it important to enhance their dispersibility for applications. Organic ligands with oleyl groups have been found to be good dispersants in less polar solvents due to their inefficient shell packing and inhibition of crystallization between particles. However, ligands with oleyl structures may contain impurities that could affect the properties of the nanoparticles. This study investigates the relationship between ligand structure and dispersibility using phosphonic acid ligands, revealing that the regio- and stereochemistries of the ligand's C=C double bond, as well as the choice of solvent, play a key role in enhancing dispersibility.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Zimo Wang, Genki Horiguchi, Hidehiro Kamiya, Yohei Okada
Summary: Using tetrahydrobenzodifuran as the core architecture, novel single-benzene fluorophores are created, which possess unique and powerful photophysical properties. These fluorophores can find extensive applications in both academic and industrial settings.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Kaii Nakayama, Yohei Okada
Summary: Arene C-H aminations were achieved using a catalytic amount of DDQ photocatalyst without the need for a co-oxidant. Various functional groups, such as pyrazoles, triazoles, tetrazoles, purines, and tert-butoxycarbonyl amine, were successfully attached to benzene via amination. The mechanism of this reaction, involving the reactivation of DDQH2 to DDQ under UV light irradiation, is still not fully understood, but the presence of O2 and/or a solvent as terminal oxidants is suggested.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Sota Adachi, Naoya Maeta, Kaii Nakayama, Zimo Wang, Yasuhiro Hashimoto, Yohei Okada
Summary: Both intermolecular and intramolecular electron transfers play important roles in determining the synthetic outcomes of photochemical and electrochemical reactions. In this study, dispersed TiO2 nanoparticles in combination with methoxybenzene were found to be a unique heterogeneous photocatalyst for facilitating the formation of novel cyclobutanes. The results suggest that methoxybenzene is adsorbed onto the TiO2 surface, leading to a pseudo-intramolecular electron transfer with the forming cyclobutane radical cation.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Physical
Genki Horiguchi, Atsuko Uesaka, Tatsuya Sudo, Yukina Ito, Hidehiro Kamiya, Yohei Okada
Summary: Colloidal nanoparticles with unique properties can be stabilized by organic ligands. By functionalizing the surface of nanoparticles, we achieved successful dispersion of various nanoparticles in different solvents.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2023)
Review
Electrochemistry
Kazuhiro Okamoto, Kazuhiro Chiba
Summary: In this paper, we summarize the research progress in the application of electrochemical methodology for skeletal modification in synthetic chemistry. By using specific electrolyte systems, the reactivity of oxidative electrochemical reactions can be significantly enhanced.
