Article
Chemistry, Multidisciplinary
Peng Wu, Shengheng Yan, Wenhan Fang, Binju Wang
Summary: Cluster-continuum model calculations were used to investigate the mechanism of water oxidation catalyzed by a mononuclear copper complex. The most favorable pathway involved the nucleophilic attack of OH- onto the L center dot+-Cu-II-OH- intermediate. A catalytic cycle for the mononuclear copper complex-catalyzed water oxidation was proposed based on the calculations.
Article
Chemistry, Physical
Zhiyao Duan, Graeme Henkelman
Summary: This study uses global optimization and constant-potential density functional theory to simulate the complete process of Pt dissolution, revealing the formation and dissolution mechanism of a two-dimensional Pt surface oxide. The findings provide a fundamental understanding of Pt dissolution under potential cycling, which is essential for the rational design of durable Pt-based cathodes for fuel cells.
Article
Chemistry, Multidisciplinary
Katrine L. Svane, Jan Rossmeisl
Summary: High-entropy oxides are composed of five or more metals, offering a broad composition space for property optimization. In catalysis applications, different local atomic environments lead to a distribution of binding energies for catalytic intermediates. By performing density functional theory calculations and modeling, it is possible to maximize catalytic activity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Yu-Feng Ding, Shuang-Feng Yin, Meng-Qiu Cai
Summary: This study investigates the mechanisms of photocatalytic toluene selective oxidation reactions, as well as the influence of water on these reactions. The results show that the oxidation potential of the photocatalyst is crucial for efficient catalysis, and the dehydration reaction is the rate-determining step for converting toluene into benzaldehyde. Furthermore, water has a dual role in photocatalytic reactions.
Article
Chemistry, Physical
Mingming Luo, Chao Liu, Meiling Liu, Shaik Gouse Peera, Tongxiang Liang
Summary: This study systematically investigated the mechanism of CO oxidation on doped graphene catalysts through DFT calculations, finding that FeFe@C6, FeCo@C6, and FeNi@C6 are efficient for CO oxidation. Additionally, heteronuclear dimeric catalysts FeCo@C6 and FeNi@C6 exhibit better catalytic activity and lower energy barriers compared to homonuclear dimeric catalyst FeFe@C6.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Man Li, Rong-Zhen Liao
Summary: Density functional theory calculations were used to elucidate the water oxidation mechanism catalyzed by polyanionic tetramanganese complex. Theoretical results showed that sequential proton-coupled electron transfer oxidations led to the formation of an oxygen radical, facilitating the formation of O-O bond. Subsequent oxidation reactions enabled the release of oxygen.
Article
Chemistry, Multidisciplinary
Yelu Shi, Gianna Stella, Jia-Min Chu, Yong Zhang
Summary: This study reveals the importance of HNO binding and a proton-coupled electron transfer mechanism for HNO reaction through quantum chemical research on Cu cyclams. The results indicate that steric effect is the primary factor, and electronic factor is the secondary factor, but the combined effects can lead to unexpected reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Jianan Li, Jili Li, Tao Liu, Lin Chen, Yefei Li, Hualin Wang, Xiurong Chen, Ming Gong, Zhi-Pan Liu, Xuejing Yang
Summary: Urea electrolysis is a promising technology for simultaneous H-2 production and nitrogen suppression in water energy production. However, prevalent nickel-based catalysts may over-oxidize urea into NO2- products, posing potential environmental hazards. Through experiments and calculations, a nitrogen-fate network was derived, leading to the development of a polyaniline-coating strategy to increase N-2 production. These findings offer insights into nitrogen fate in water-energy systems.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Hongling Huang, Xuedan Song, Chang Yu, Qianbing Wei, Lin Ni, Xiaotong Han, Huawei Huang, Yingnan Han, Jieshan Qiu
Summary: In this study, a novel liquid-liquid-solid system is reported to regulate the selectivity of benzyl alcohol electrooxidation. The selectivity of benzaldehyde increases 200-fold from 0.4% to 80.4% compared with the liquid-solid system at a high current density of 136 mA cm(-2), which is the highest one up to date. In the tri-phase system, the benzaldehyde peroxidation is efficiently suppressed, with the conversion of benzaldehyde being decreased from 87.6% to 3.8%. The as-produced benzaldehyde can be in situ extracted to toluene phase and separated from the electrolyte to get purified benzaldehyde. This strategy provides an efficient way to enhance the selectivity of electrocatalytic cascade reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Samuel D. L. Holman, Alfie G. Wills, Neal J. Fazakerley, Darren L. Poole, Diane M. Coe, Leonard A. Berlouis, Marc Reid
Summary: An electrochemical method for the synthesis of substituted isoxazoline cores is presented, which can efficiently convert both aryl and alkyl aldoximes. In-situ reaction monitoring and theoretical calculations support the mechanism and reaction pathway.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Physical
Mingyu Wan, Zhiyong Gu, Fanglin Che
Summary: By modifying Cu surface with SAM, the stability, activity, and selectivity of CO2 electroreduction to C-2 chemicals can be improved, mainly through decreasing surface energy, facilitating CO2 activation and C-C coupling, as well as inducing confinement effects and charge transfer.
Article
Chemistry, Multidisciplinary
Yong Wu, Shanshan Cao, Iskander Douair, Laurent Maron, Xihe Bi
Summary: The [2+1] cycloaddition reaction of a metal carbene with an alkene often suffers from side reactions, leading to lower yields of cyclopropanation products. By adding a low concentration of diazo compound to alkenes, it was found that AgOTf catalysis can efficiently produce cyclopropane products from hindered alkenes.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Die Bai, Man Li, Rong-Zhen Liao
Summary: The merging of transition-metal-catalyzed C-H bond activation with electro-oxidation has become a promising approach for oxidative C-H bond functionalization. However, the specific effects of electro-oxidation on the reaction mechanism of transition-metal catalysis have rarely been studied. In this computational study, the rhodium-catalyzed electrochemical C-H phosphorylation of 2-phenylpyridine by diphenylphosphine oxide was investigated to reveal the mechanistic details. The calculations showed that C-H activation prefers to occur at the Rh(III) state, P-H activation at the Rh(IV) state, and reductive elimination at the Rh(V) state. The mechanistic insights obtained from this study are valuable for understanding transition-metal-catalyzed electro-oxidative C-H bond functionalization.
Article
Chemistry, Multidisciplinary
Marin Puget, Viacheslav Shcherbakov, Sergey Denisov, Philippe Moreau, Jean-Pierre Dognon, Mehran Mostafavi, Sophie Le Caer
Summary: The nature of the primary species formed in FEC depends on the amount of FEC in the solution, which will affect its performance in the electrolyte.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Raphael Robidas, Claude Y. Legault
Summary: A mechanism is proposed to explain the formation of benzobicyclo[3.2.0]heptane derivatives from 1,7-enyne derivatives bearing a terminal cyclopropane, which has been previously reported.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Rocio Redon, Tania Gonzalez-Garcia, Lorena Espinoza-Flores, Alfonsina Reyes-Mosso, Erika Martin, V. M. Ugalde-Saldivar
Summary: Palladium(0) nanoparticles were synthesized in colloidal suspension using different solvents and reducing methods, resulting in varying nanoparticle sizes that influenced catalysis. The best conversion in C-C Heck catalysis was observed under the minimum reaction conditions at 120 degrees C and 10 h, with N,N-dimethylformamide as solvent and no reducing agent.[dimethylformamide] This system produced the largest nanoparticles in dispersion, highlighting the importance of nanoparticle size in achieving high yields in C-C Heck catalysis.
Review
Chemistry, Inorganic & Nuclear
Virginia Gomez-Vidales, Ivan Castillo
Summary: Synthetic chemists are working to mimic the active site of copper monooxygenase enzymes and test their reactivity with dioxygen using specific ligands. The identification of Cu-II-superoxos as key reactive intermediates in C-H activation provides support for these species in enzymatic systems.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Eric Navarrete, Frank Guell, Paulina R. Martinez-Alanis, Eduard Llobet
Summary: Different thicknesses of Au films were used in the growth of ZnO nanowires, with the 6 nm thick layers showing the most stable and repeatable gas sensing properties. Despite ZnO nanowires grown using the thickest Au layers reaching the highest responses under dry conditions, those grown using the thinnest Au film were more resilient at detecting NO2 in the presence of ambient moisture. The gas sensing results were discussed in light of defects and Au impurities in the ZnO nanowires, as revealed by characterization techniques such as X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Electrochemistry
Fernando Landgrave-Barbosa, Andres F. Marmolejo-Valencia, Alejandro Baray-Calderon, Hailin Hu, Julio Cesar Aguilar-Cordero, Carlos Amador-Bedolla, Victor M. Ugalde-Saldivar
Summary: This study investigates the poly(3-hexylthiophene) (P3HT) thin films deposited on fluorine-doped tin oxide (FTO) glass substrates using the spin-coating process. The results show abnormal spectra in films with thicknesses between 40 and 50 nm, possibly due to the formation of defects. Energy-resolved electrochemical impedance spectroscopy (ER-EIS) experiments reveal a thickness dependence of the lowest unoccupied molecular orbital (LUMO) energy level, while the highest occupied molecular orbital (HOMO) level remains constant.
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Saul F. Teloxa, Miguel Mellado-Hidalgo, Stuart C. D. Kennington, Pedro Romea, Felix Urpi, Gabriel Aullon, Merce Font-Bardia
Summary: A direct and asymmetric aldol reaction between N-azidoacetyl-1,3-thiazolidine-2-thione and aromatic aldehydes catalyzed by a chiral nickel(II)-Tol-BINAP complex has been developed. The reaction gives anti alpha-azido-beta-silyloxy adducts with excellent stereocontrol and high yields. The removal of thiazolidinethione allows for the synthesis of a wide array of enantiomerically pure derivatives, providing a new route to di- and tripeptide blocks containing a beta-aryl-beta-hydroxy-alpha-amino acid.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Physical
Radu A. Talmazan, J. Refugio Monroy, Federico del Rio-Portilla, Ivan Castillo, Maren Podewitz
Summary: Encapsulating Cu(I) within a specific compound enhances the efficiency and yield of C-N coupling reactions, making this supramolecular catalyst desirable for sustainable processes. Computational investigations reveal the working mechanism of the catalyst and provide theoretical support for improving homogeneous catalysis efficiency.
Article
Chemistry, Inorganic & Nuclear
Armando Berlanga-Vazquez, Radu A. Talmazan, Carlos A. Reyes-Mata, Edmundo G. Percastegui, Marcos Flores-Alamo, Maren Podewitz, Ivan Castillo
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Armando Berlanga-Vazquez, Radu A. Talmazan, Carlos A. Reyes-Mata, Edmundo G. Percastegui, Marcos Flores-Alamo, Maren Podewitz, Ivan Castillo
Summary: Functionalization of p-tert-butylcalix[8]arene with phenanthroline at the phenolic rim created two regioisomers, with substitution at positions 1 and 5 producing a known symmetric regioisomer and substitution at positions 1 and 4 producing a newly described symmetric regioisomer. The C-S coupling reaction using the newly synthesized regioisomer showed lower activity compared to the previously reported system, potentially due to a difference in the exposed catalytic center caused by a deformation in the regioisomer's structure. Detailed computational investigations confirmed the 1,4-connectivity and revealed the influence of the calix[8]arene macrocyclic morphology on accessible conformations.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Francisco A. A. Gomez-Mudarra, Gabriel Aullon, Jesus Jover
Summary: The Cu-catalyzed Suzuki-Miyaura coupling between highly fluorinated aryl boronate esters and aryl iodides has been investigated using DFT calculations. The proposed reaction mechanism suggests that the rate-determining step is the oxidative addition of the aryl iodide to the copper catalyst. Computational studies on alternative reactions with different substituents provide a reaction barrier database that considers the electronic properties of various functional groups. Statistical learning techniques, specifically multi linear regression (MLR) modeling, reveal that both electron poor aryl boronate esters and aryl iodides result in lower reaction barriers. The combination of the reaction barrier database and MLR models allows for the generation of an electronic substrate map for estimating the reaction outcome in analogous Suzuki-Miyaura reactions between aryl boronate esters and iodobenzenes.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Polymer Science
Rene A. Hauyon, Denis Fuentealba, Nancy Pizarro, Maria C. Ortega-Alfaro, Victor M. Ugalde-Saldivar, Patricio A. Sobarzo, Jean Medina, Luis Garcia, Ignacio A. Jessop, Carmen M. Gonzalez-Henriquez, Alain Tundidor-Camba, Claudio A. Terraza
Summary: A new polymer material, p-TPS-DMAC-TRZ, with high thermal stability and good solubility was successfully synthesized, which maintained the fluorescence properties of DAMC-TRZ while improving thermal stability and morphological properties. The results showed that p-TPS-DMAC-TRZ is a promising candidate for use as a light-emitting layer in OLED devices.
Article
Chemistry, Physical
Eduardo Martinez-Gonzalez, Carlos Amador-Bedolla, Victor M. Ugalde-Saldivar
Summary: Finding water-soluble organic negolytes that can store two electrons is crucial for increasing the charge storage capacity of next-generation flow batteries. In this study, the reduction process of the gallocyanine compound was investigated and found to exhibit a reversible process of adsorption and diffusion pathways. The reversible redox chemistry of the compound was further confirmed through testing a flow cell, which showed excellent battery performance.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Chemistry, Analytical
Guillem Montana-Mora, Xueqiang Qi, Xiang Wang, Jesus Chacon-Borrero, Paulina R. Martinez-Alanis, Xiaoting Yu, Junshan Li, Qian Xue, Jordi Arbiol, Maria Ibanez, Andreu Cabot
Summary: A new catalyst Pd2Sn0.8P for formate oxidation reaction (FOR) is synthesized using colloidal method. The Pd2Sn0.8P-based electrodes exhibit outstanding catalytic activities with high mass current densities. The excellent catalytic performance is further enhanced by increasing the temperature.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Physical
Rebecca Leblay, Rafael Delgadillo-Ruiz, Christophe Decroos, Christelle Hureau, Marius Reglier, Ivan Castillo, Bruno Faure, A. Jalila Simaan
Summary: This study aims to evaluate the oxidative depolymerization of polysaccharides with different molecular structures and establish a reproducible activity assay. The experimental results demonstrated that bioinspired complexes can promote polysaccharide depolymerization, and the mechanistic pathways and catalyst stability were discussed.
Article
Chemistry, Inorganic & Nuclear
Jaime Ponce-de-Leon, Marconi N. Penas-Defrutos, Andrea Velez, Gabriel Aullon, Pablo Espinet
Summary: Complexes trans-[PdX2L2] (X = Cl and Br), where L is 1-(PR2),2-(CH=CH-C(O)Ph)-C6F4 (R = Ph, Cy, and iPr), exhibit phosphorescent emission in the solid state, while free ligands with shorter lifetimes display fluorescent behavior. However, derivatives with halide replaced by CN- or Pd replaced by Pt show no emission. DFT calculations reveal that only the hybridization of orbitals of the MX2 moiety with those of the ligand's chalcone fragment is significant for the LUMO of the emissive compounds, leading to observable luminescence.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Araceli de Aquino, Francisco J. Caparros, Gabriel Aullon, Khai-Nghi Truong, Kari Rissanen, Joao Carlos Lima, Laura Rodriguez
Summary: The synthesis of a gold(i) alkynyl-fluorene compound containing a diphosphane has been achieved easily. The compound shows a suitable conformation for molecular recognition processes. Stronger interaction has been observed between the compound and polyaromatic hydrocarbons, particularly anthracene. The compound has also been immobilized to enhance room temperature phosphorescence.
DALTON TRANSACTIONS
(2022)