Article
Chemistry, Multidisciplinary
Ester M. Di Tommaso, Per-Ola Norrby, Berit Olofsson
Summary: Vinylbenziodoxolones have been identified as efficient reagents for electrophilic vinylations under metal-free conditions. This paper presents the first mechanistic investigation of VBX vinylations, providing insights into the regio- and stereochemical outcome. The findings can be applied to predict the regioselectivity in vinylations of other nucleophile classes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Yanhong Liu, Aili Feng, Rongxiu Zhu, Chengbu Liu, Dongju Zhang
Summary: Density functional theory (DFT) calculations were performed to investigate the mechanism of copper-catalyzed four-component borocarbonylative coupling of alkenes with alkyl halides using bis(pinacolato)diboron as the boron reagent under CO atmosphere. The theoretical results revealed an unexpected reaction mechanism involving CuI as the sole catalyst, with a two-ligand relay mechanism and no radical participation, proceeding through SN2-type C-C coupling. The experimental observations of regio- and chemoselectivities, as well as the inhibition of the reaction by radical trapping reagents, were rationalized by the theoretical analysis.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Organic
Fengyue Zhao, Peiyuan Yu, Yu Chen, Fang Liu, K. N. Houk
Summary: Experimental and computational studies have shown that pi-facial selectivity in the Diels-Alder cyclo-addition reaction of 5-monosubstituted cyclopentadienes is mainly influenced by polar groups, while the stereoselectivity of 5,5-unsymmetrically substituted cyclopentadienes is determined by a combination of factors such as substituent conformations and steric/electronic effects between diene and dienophile. This research provides insights into the factors affecting the stereoselectivity of cycloaddition reactions involving cyclopentadienes, with predictions for future studies in this area.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Biochemical Research Methods
Gabriel Amankwah, Isaac Ofori, Joshua Atta-Kumi, Caroline R. Kwawu, Richard Tia, Evans Adei
Summary: In this study, density functional theory was used to investigate the chemoselectivities and regio-selectivities of the [3 + 2] cycloaddition reaction of phenyl (2-thienyl) thioketone derivatives with nitrile oxide and diazopropane derivatives. The reactions were found to proceed through an asynchronous one-step mechanism, with the thiocarbonyl site of the thioketone being the most reactive center. The results were consistent with experimental observations.
JOURNAL OF MOLECULAR GRAPHICS & MODELLING
(2023)
Article
Materials Science, Multidisciplinary
Mikhail M. Maslov, Alexey I. Kochaev, Margarita A. Gimaldinova, Anastasiya A. Grekova, Konstantin P. Katin
Summary: A series of new covalent crystals inspired by the carbon tesseract or hypercubane has been introduced and their packing structures and electronic characteristics have been analyzed. The hypercubane crystals were found to have simple cubic (sc), body-centered cubic (bcc), and face-centered cubic (fcc) packing. The sc and bcc crystals were identified as semiconductors with band gaps of 2.23 and 1.46 eV, respectively, while the fcc crystal exhibited metallic nature. The characteristic peaks in the Raman, IR, and UV-visible spectra were obtained for the identification of the different hypercubane crystals.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Angel Ho, Austin Pounder, Krish Valluru, Leanne D. Chen, William Tam
Summary: An experimental and theoretical investigation on iridium-catalyzed hydroacylation was reported, providing a variety of hydroacylated bicyclic adducts with complete stereo- and regioselectivity. The mechanism and origins of selectivity were examined at the theoretical level.
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Ying Wang, Ning Xu, Weiwei Li, Jiaojiao Li, Yijun Huo, Wenrong Zhu, Qiang Liu
Summary: An efficient electrochemical method has been developed for the direct synthesis of complicated 1,3-diselenyl-dihydroisobenzofurans from substituted o-divinylbenzenes and diselenides under external oxidant free conditions at room temperature. A radical mechanism is proposed for this novel and practical transformation.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Jinxin Zou, Yao Chen, Wei Feng
Summary: In this study, QM/MM calculations were used to investigate the mechanisms of DOPA radical generation, transfer, and regeneration in metal-free class Ie ribonucleotide reductase. The calculations revealed key residues and steps involved in these processes.
COMPUTATIONAL AND STRUCTURAL BIOTECHNOLOGY JOURNAL
(2022)
Article
Chemistry, Organic
Yunshuai Huang, Xiaohui Jin, Fenglian Zhang, Yifeng Wang
Summary: The study reported a regioselective radical hydroboration reaction of alkenes for the synthesis of alpha-boryl functionalized molecules. The reaction features specific alpha-regioselectivity, mild reaction conditions, and good substrate scope.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Physics, Applied
Andrew C. Antony, Dean Thelen, Nikolay Zhelev, Kaveh Adib, Robert G. Manley
Summary: The study reveals that contact charging between metals and hydroxylated SiO2 induces electronic states at the SiO2 surface, with the magnitude of these states varying with the type of metal and the density of surface defect states.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Kaixia Sui, Yuting Leng, Yangjie Wu
Summary: A highly efficient method for synthesizing difluoroarymethyl-substituted benzimidazo[2,1-a]isoquinolin-6(5H)-ones was developed using 2-arylbenzoimidazoles with alpha,alpha-difluorophenylacetic acid as reaction substrates through radical cascade cyclization. The strategy offers excellent functional group tolerance and enables the generation of the desired products in good yields under base- and metal-free conditions.
Article
Chemistry, Multidisciplinary
Paul Geerlings, Frank De Proft
Summary: The necessity of incorporating new external variables in the context of conceptual DFT (CDFT) is discussed. Electric and magnetic fields, mechanical forces, and confinement are proposed as valuable new variables. The study shows that these new variables are important for understanding chemical phenomena under different conditions.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2023)
Article
Chemistry, Organic
Fu-Yu Li, Bei Wang, Hong Xu, Yao Xiao, Dong-Wei Huang, Ji-Yu Wang
Summary: The convenient synthesis of diverse and complex poly-substituted beta-alkenyl valerolactones is achieved through Fe(iii)-catalyzed reduction radical tandem strategy of 2,3-dienoates and allyl alcohols. The allyl alcohols can undergo simultaneous transformations into alkyl radicals and allyl ester intermediates under Fe(iii) catalysis, which then react via Michael addition to form the desired products. Notably, this method also enables the preparation of spiro-valerolactones and cyclo-valerolactones, as well as the transformation of beta-alkenyl valerolactones into previously unreported pyrazole lactone compounds.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Review
Biochemistry & Molecular Biology
Savas Kaya, Mihai V. Putz
Summary: This article explores the concept of chemical hardness and its implementation in conceptual density functional theory from innovative perspectives. It examines the equalization between electronegativity and hardness of atoms in molecules connected with the softness kernel, and the relationship between the electronic sharing index and the charge transfer in bonding. It also discusses the maximum hardness principle and the minimum polarizability principle in relation to chemical stability. Additionally, important applications of the chemical hardness concept in solid-state chemistry are reviewed, supporting the validity of electronic structure principles regarding chemical hardness and polarizability in this field.
Article
Engineering, Environmental
Qixin Zhou, Jinsong Zhou, Lingtao Zhou, Chenghang Zheng, Zhuang Liu, Yang Lu, Bohao Li
Summary: DFT-D2 theoretical calculations were used to investigate the adsorption behaviors and mechanisms of elemental mercury (Hg-0) on the low-Miller index mackinawite surface (FeS(001)-S surface) with the involvement of carbon or sulfur. The results showed that carbon atom can act as a linker between the substrate and the Hg atom, while sulfur-doped surface led to the formation of a chemical bond between the Hg atom and the surface. The adsorption process followed Langmuir-Hinshelwood Mechanism.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Xavier Deraet, Jan Turek, Mercedes Alonso, Frederik Tielens, Bert M. M. Weckhuysen, Monica Calatayud, Frank De Proft
Summary: This paper investigates the adsorption behavior of single late transition metals on a defect-free anatase surface using periodic density functional theory calculations. The results reveal that the interaction strength between the transition metals and the support can be attributed to electron transfer, s-d orbital hybridization effects, or a synergistic effect between both factors. Palladium shows deviating adsorption behavior, which is likely associated with the lower dissociation enthalpy of the Pd-O bond. The reactivity of these systems is evaluated using the Fermi weighted density of states approach, and a model is proposed to predict the adsorption strength of CO on anatase-supported d-metal atoms.
Article
Chemistry, Organic
Javier E. Alfonso-Ramos, Ruben Van Lommel, David Hernandez-Castillo, Frank De Proft, Roy Gonzalez-Aleman, Erik V. Van der Eycken, Gerardo M. Ojeda-Carralero
Summary: 3-Dipolar cycloadditions are commonly used to form five-membered heterocycles, but the cycloadditions involving acyl-isocyanide ylides have not been well explored by the chemical community. In this study, we investigated the mechanistic features of the reaction between acyl-isocyanide ylides and dipolarophiles using density functional theory calculations. We explained the experimental results and predicted opposite regioselectivity for electron-poor and electron-rich dipolarophiles. This study provides insights for the design of new cycloaddition reactions based on the acyl-isocyanide ylides motif.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Mercedes Alonso, Frank De Proft, Tom Bettens, Paul Geerlings
Summary: Anti-Felkin-Anh diastereoselectivity can be achieved by stretching the ketone with a mechanical pulling force. A mechanochemical Felkin-Anh model is proposed based on the distance between the pulling points. The model is validated by density functional theory calculations and the risk of bond rupture is minimized.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Ana V. Cunha, Remco W. A. Havenith, Jari van Gog, Freija De Vleeschouwer, Frank De Proft, Wouter Herrebout
Summary: In this study, the interaction between the halogen atom X and the aromatic ring in the halogen bond complexes CF(3)Xmiddot middot middot Y and C(2)F(3)Xmiddot middot middot Y (with Y = furan, thiophene, selenophene and X = Cl, Br, I) was investigated using DFT and CCSD(T) methods. It was found that the interaction with the pi-bonds in a perpendicular orientation is stronger than the interaction with the in-plane lone pairs of the heteroatom of the aromatic cycle. The interaction energy is dominated by electrostatic, orbital, and dispersion interactions, and the strength of the interaction follows the trend Cl < Br < I.
Article
Chemistry, Multidisciplinary
Stephen E. Brown, Ioanna Mantaloufa, Ryan T. Andrews, Thomas J. Barnes, Martin R. Lees, Frank De Proft, Ana V. Cunha, Sebastian D. Pike
Summary: The molecular titanium-oxo cluster [Ti6O6((OPr)-Pr-i)(6)((O2CBu)-Bu-t)(6)] (1) can be activated by UV light to produce a mixed valent (photoreduced) Ti (iii/iv) cluster, along with alcohol and ketone organic products. Mechanistic studies show a two-electron mechanism utilizing the cluster structure for multielectron reactions. The photoreduced products [Ti6O6((OPr)-Pr-i)(4)((O2CBu)-Bu-t)(6)(sol)(2)] can be isolated and characterized, and undergo onward oxidation under air. The redox reactivity described is only possible in a cluster with multiple Ti sites.
Article
Chemistry, Multidisciplinary
Alejandro Lorente, Andres Ochoa, Julio Rodriguez-Lavado, Silvia Rodriguez-Nuevalos, Pablo Jaque, Salvador Gil, Jose A. Saez, Ana M. Costero
Summary: A new selective fluorogenic chemosensor for Hg2+ has been studied, which incorporates a calixarene derivative and a BODIPY core. The changes in its fluorogenic properties in DMSO and CHCl3 have been analyzed, and through dilution studies and molecular modeling, it was explained that the behavior involves the formation of a J-dimer and the sensing mechanism of Hg2+.
Article
Chemistry, Inorganic & Nuclear
Bin Wang, Chunying Rong, Ming Lei, Shubin Liu, Frank De Proft
Summary: Designing efficient and selective catalysts for carbon dioxide reduction is an active area of research in homogeneous catalysis. In this study, the catalytic activity of a newly reported Mn(I)-PNP-pincer catalyst with an embedded aromatic ring is investigated. The study systematically examines the catalyst's capability to yield different products and explores the importance of ligand aromaticity and steric effects on metal-ligand cooperativity. The reactivity of the catalyst is probed using conceptual density functional theory and an information-theoretic approach, leading to a novel partitioning of the reaction coordinate into three relevant regions. The results demonstrate that different properties govern the reactivity in these different regions, such as steric effects, electrophilicity/nucleophilicity, or aromaticity. The methodology and analytical tools employed in this study have the potential to be generalized and extended to other catalytic systems, offering insights towards designing improved catalysts.
INORGANIC CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Lise Vermeersch, Frank De Proft, Vicky Faulkner, Freija De Vleeschouwer
Summary: This study analyzed the governing factors in Lewis acid and non-covalent catalysis of three types of Diels-Alder reactions. The stability of the non-covalent interaction donor-dienophile complex was found to significantly reduce the activation energy. Orbital interactions were shown to be the main driver for catalysis, with electrostatic interactions dominating.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Chemistry, Physical
Lieven Bekaert, Suzuno Akatsuka, Naoto Tanibata, Frank De Proft, Annick Hubin, Mesfin Haile Mamme, Masanobu Nakayama
Summary: Rechargeable batteries are essential in the transition from fossil fuels to renewable energy. Solid-state sodium ion batteries are a promising alternative to lithium-based batteries, offering improvement in safety, lifespan, sustainability, and price. The chemical stability of Na3PS4 solid-state electrolyte with sodium metal electrode has been investigated, providing new design principles for optimizing solid-state electrolytes.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Javier Oller, Pablo Jaque
Summary: In this paper, we establish a connection between the average local ionization energy, electron affinity, and electronic Fukui functions, and derive expressions for nuclear Fukui functions beyond the highest occupied molecular orbital/lowest unoccupied molecular orbital approximation. This provides a new way to interpret and study the variation of local nucleophilicity or electrophilicity with respect to nuclear displacements, and has potential applications in molecular vibrations, internal rotations, bond dissociation, and chemical reactions.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Biochemistry & Molecular Biology
Eline Desmedt, Lea Serrano Gimenez, Freija De Vleeschouwer, Mercedes Alonso
Summary: This study focuses on the application of hexaphyrins as multistate switches in nanoelectronics, and explores the role of core modifications and push-pull combinations in enhancing the nonlinear optical (NLO) contrast. The researchers use an inverse design algorithm to find functionalized redox switches with maximal NLO contrast and aim to design a three-state switch with similar NLO response for different ON states. The results show that core modifications are generally not favored when high NLO contrasts are targeted, and the arrangement of electron-donating and electron-withdrawing functional groups in push-pull combinations varies for different redox switches.
Article
Chemistry, Multidisciplinary
Cesar Barrales-Martinez, Rocio Duran, Pablo Jaque
Summary: In this study, a large set of intramolecular aminoborane-based FLPs were analyzed using density functional theory to investigate the influence of boron and nitrogen atom acidity and basicity on the reversibility of the H2 activation process. The results showed that only a few systems exhibited reversible H2 activation, with the combination of alkyl/aryl or aryl/alkyl in boron/nitrogen generating reversible systems. The electronic properties of each system were analyzed, revealing a correlation between the condensed-to-boron electrophilicity index and the reversibility of the H2 activation.
Article
Chemistry, Multidisciplinary
Cesar Barrales-Martinez, Rocio Duran, Pablo Jaque
Summary: This study investigates the catalytic activation of H2 by intramolecular aminoborane-based compounds. The results show that the acidity and basicity of boron and nitrogen atoms play a crucial role in the reversibility of the process. By analyzing the electronic properties, a rational design strategy is proposed to optimize the H2 reversible activation, thereby improving catalytic performance.