Review
Chemistry, Multidisciplinary
Ursula Biermann, Uwe T. Bornscheuer, Ivo Feussner, Michael A. R. Meier, Juergen O. Metzger
Summary: Oils and fats of vegetable and animal origin are important renewable feedstock for the chemical industry, with their industrial use increasing significantly in the past decade. Remarkable achievements in oleochemistry include reduction of fatty esters, selective oxidation of double bonds, synthesis of alkyl-branched compounds, and applications in the synthesis of polymeric materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(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, Multidisciplinary
Maike Thiele, Thomas Rose, Mart Lokov, Sophia Stadtfeld, Sofja Tshepelevitsh, Elisabeth Parman, Karina Opara, Christoph Woelper, Ivo Leito, Stefan Grimme, Jochen Niemeyer
Summary: The nature, length and number of linkers have a profound influence on the enantioselectivities in the design of novel organocatalysts based on phosphoric acids.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Natalie S. Schunck, Stefan Mecking
Summary: Sustainable sources are crucial for chemicals production, and microalgae have the potential to catalytically convert renewable substrates inside living cells, generating valuable building blocks for chemical production.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Stefanie de Roo, Felix Einsiedler, Stefan Mecking
Summary: This study demonstrates the catalytic conversion of renewable plant oils, including microalgae and waste oil, into industrially relevant alpha-olefins in the C-3 to C-10 regime. The biorefinery concept involves a catalytic sequence of ethenolysis, double bond isomerization, and subsequent ethenolysis, effectively rearranging the fatty acid chains into valuable chemical building blocks. Supercritical carbon dioxide (scCO(2)), a benign extraction and reaction solvent, is utilized.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Yasmin S. Raupp, Pia S. Loeser, Silke Behrens, Michael A. R. Meier
Summary: The study found that palladium nanoparticles, stabilized by poly(vinylpyrrolidone), catalyze the ring-opening of limonene dioxide with water, showing selectivity. Different concentrations of poly(vinylpyrrolidone) alone resulted in different selectivities towards exo-cyclic or endo-cyclic epoxide ring-opening.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Wei-Feng Zheng, Jingdan Chen, Xiaotian Qi, Zhongxing Huang
Summary: Stereoselective protonation is a challenge in asymmetric catalysis, but it can convert abundant acid feedstocks into structurally diverse chiral molecules. Researchers have demonstrated an anchoring group strategy to create additional catalyst-substrate interactions, allowing enantioselective decarboxylative protonation to produce alpha-amino acids. This malonate-based synthesis introduces side chains and enables the access of structurally and functionally diverse amino acids.
Article
Chemistry, Multidisciplinary
Jia-Bin Pan, Xuan-Ge Zhang, Yi-Fan Shi, Ai-Cui Han, Yu-Jia Chen, Jing Ouyang, Mao-Lin Li, Qi-Lin Zhou
Summary: We report the discovery of high-pK(a) Bronsted acid catalysts that enable the asymmetric transformation of free carbenes into chiral alpha-amino acid derivatives by insertion into N-H bonds of amines. Under visible light irradiation, diazo compounds generate high-energy free carbenes that react with amines to form free ylide intermediates. The newly designed high-pK(a) Bronsted acids, chiral spiro phosphamides, facilitate the proton transfer of ylides to afford the products. Computational and kinetic studies provide insights into the rational design of proton-transfer catalysts and the mechanisms underlying their acceleration and stereocontrol in this transformation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Jia-Bin Pan, Zhi-Chun Yang, Xuan-Ge Zhang, Mao-Lin Li, Qi-Lin Zhou
Summary: Here, we present a method for enantioselective phosphoric acid catalyzed amination of ketenes generated from α-aryl-α-diazoketones. Mechanistic studies elucidated the reaction pathway and explained how the catalyst expedited the transformation and controlled the enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Ziwei Gu, Li Zhang, Haijun Li, Shanshan Cao, Yanli Yin, Xiaowei Zhao, Xu Ban, Zhiyong Jiang
Summary: Catalytic deracemization is an ideal synthetic strategy with high atom utilization efficiency. This study presents a new platform based on photoredox-neutral catalysis for efficient enrichment of valuable analogues like alpha-amino esters through photocatalysis and chiral Bronsted acid catalysis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Kaixue Xie, Martin Oestreich
Summary: Readily available cyclohexa-2,5-dien-1-ylcarbonyl chloride derivatives were used as stable HCl surrogates for transfer hydrochlorination of alkenes and alkynes. B(C6F5)(3) facilitated the stepwise fragmentation of acyl chlorides, allowing the addition of HCl across C-C double and triple bonds with Markovnikov selectivity at room temperature.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Lucas H. R. Passos, Victor Martinez-Agramunt, Dmitry G. Gusev, Eduardo Peris, Eduardo N. dos Santos
Summary: The reduction of esters and aldehydes to alcohols is an important reaction in the chemical industry. The behavior of three commercially available Ru-catalysts for the hydrogenation of these feedstocks is reported. Selective hydrogenation of the ester or aldehyde functionality while keeping the C=C double bond intact is possible, and mild reaction conditions and a sustainable solvent are suitable for these catalytic hydrogenations.
Article
Chemistry, Multidisciplinary
Cederic Ver Elst, Robby Vroemans, Mathias Bal, Sergey Sergeyev, Carl Mensch, Bert U. W. Maes
Summary: A selective method of producing levulinic acid, a key biorenewable platform molecule, has been developed from muconic acid through high-temperature water heating. This method offers the possibility of synthesizing novel levulinic acid derivatives and demonstrates superior performance as a plasticizer in comparison to commercial benchmarks.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Basil Raju Karimadom, Shalaka Varshney, Tomer Zidki, Dan Meyerstein, Haya Kornweitz
Summary: The catalytic hydrolysis of BH4- on Au(111) surface was studied using DFT and compared to Ag(111) surface. The results show significant differences in the reaction mechanisms between the two surfaces, with only three of the four hydrogen atoms from BH4- transferred to the Au surface. The presence of surface H atoms enhances the generation of H-2.
Review
Chemistry, Multidisciplinary
Susana Estopina-Duran, James E. Taylor
Summary: This review outlines recent advances in Bronsted acid-catalysed dehydrative substitution reactions for C-C, C-O, C-N and C-S bond formation. It highlights the wide range of processes accessible using simple alcohols as the formal electrophile, while discussing current limitations and possible future research directions.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Computer Science, Interdisciplinary Applications
Himaghna Bhattacharjee, Jackson Burns, Dionisios G. Vlachos
Summary: The recent advances in deep learning, generative modeling, and statistical learning have led to a renewed interest in traditional cheminformatics tools and methods. This paper introduces AIMSim, an accessible cheminformatics platform for performing similarity operations on molecular datasets. AIMSim provides a unified platform to perform similarity-based tasks on molecular datasets and includes support for command-line use as well as a Graphical User Interface for code-free utilization with fully interactive plots.
COMPUTER PHYSICS COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Mehdi Zare, Pavel A. Kots, Stavros Caratzoulas, Dionisios G. Vlachos
Summary: The density and conformation of polyethylene at the interface with Pt(111) are influenced by the length, side chain length, and concentration of the polymer. Short chains are mostly located on the Pt surface, while longer chains exhibit broader conformational distributions. Branching significantly affects the conformations of long chains and can lead to a wider carbon product distribution upon C-C bond cleavage.
Article
Multidisciplinary Sciences
Song Shi, Piaoping Yang, Chaochao Dun, Weiqing Zheng, Jeffrey J. J. Urban, Dionisios G. G. Vlachos
Summary: The researchers synthesized hyper-crosslinked porous polymer catalysts with different functional groups to tune the active site environment. They found that -OH groups enhanced the hydrogenation rate of substrates containing carbonyl groups, while -CH3 groups promoted the activation of non-H bond substrates. This synthetic strategy offers a new approach for selective catalysis.
NATURE COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Yung Wei Hsiao, Darien K. Nguyen, Kewei Yu, Weiqing Zheng, Panagiotis Dimitrakellis, Dionisios G. Vlachos
Summary: We use a nonthermal, He/O-2 atmospheric plasma as an efficient method of surface functionalization for activated carbons. Plasma treatment rapidly increases the surface oxygen content of the activated carbon, introducing a diverse range of carbonyl and carboxyl functionalities. This surface functionalization improves the catalytic synthesis, reducing particle size, suppressing agglomerate formation, and increasing metal dispersion, leading to improved yield of biofuel replacement compound.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Engineering, Chemical
Nawaf M. Alghamdi, Dionisios G. Vlachos, S. Mani Sarathy
Summary: This study presents a thermodynamically consistent, density functional theory (DFT)-based parametrized microkinetic model that predicts CO oxidation on Rh at stoichiometric and lean conditions. The model accurately simulates experimental data and literature data collected under different conditions. This microkinetic mechanism can contribute to optimizing three-way catalysts to reduce CO emissions and propose cheaper alternative catalysts.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Medicinal
Bharat Medasani, Sashank Kasiraju, Dionisios G. G. Vlachos
Summary: Microkinetic modeling is a valuable tool for combining microscale atomistic data with macroscale reactor observables. This paper introduces an open-source microkinetic modeling toolkit called OpenMKM, which is primarily designed for heterogeneous catalytic reactions but can also be used for homogeneous reactions. OpenMKM is built on top of the Cantera software and allows users to input reaction mechanisms in human-readable files or use automatic generators. It provides built-in interfaces for solving ordinary differential equations and differential-algebraic equations, and offers various ideal reactors and energy balance options. OpenMKM also integrates with pMuTT for thermochemistry input file generation and RenView for visualization and reaction pathway analysis.
JOURNAL OF CHEMICAL INFORMATION AND MODELING
(2023)
Article
Chemistry, Multidisciplinary
Yuqing Luo, Esun Selvam, Dionisios G. Vlachos, Marianthi Ierapetritou
Summary: The growing amount of plastic waste poses a threat to the environment. Polyethylene terephthalate (PET) is widely used in fibers and packaging, making it one of the most common plastics. Recent research has proposed chemical recycling and upcycling methods to produce valuable products from PET waste. This study evaluates the environmental and economic performance of various technologies, including microwave-assisted heterogeneous glycolysis, through techno-economic analysis and life cycle assessment. The results show that the microwave-assisted glycolysis process can reduce production costs and emissions compared to traditional routes, making it an effective method for handling distributed PET waste.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Borja Hernandez, Pavel Kots, Esun Selvam, Dionisios G. Vlachos, Marianthi G. Ierapetritou
Summary: This study compares the techno-economics and life cycle assessment of different thermochemical depolymerization technologies for generating various products from LDPE waste. Pyrolysis followed by conversion to lubricant oils is the most profitable technology, while hydrogenolysis has the lowest CO2 emissions at large scales. Hydrocracking is environmentally friendly but requires optimization of the supply chain. Gasification and hydrothermal liquefaction have high emissions, requiring carbon capture systems. Lowering sorting costs, collecting waste near big cities, building large plants, and achieving high selectivity to value-added products are critical for successful plastic waste management.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Gwendolyn J. Gregory, Cong Wang, Sunitha Sadula, Sam Koval, Raul F. Lobo, Dionisios G. Vlachos, Eleftherios Terry Papoutsakis
Summary: There is limited research on microbial deconstruction or functionalization of polyolefin's recalcitrant backbone. However, microbes can utilize polyolefin deconstruction products. In this study, researchers combined chemical catalysis and bioconversion to valorize polyethylene (PE) deconstruction products. They found microbial consortia derived from soil from local recycling plants that can utilize the PE-deconstruction product mix as the sole carbon source.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Green & Sustainable Science & Technology
Pavel A. Kots, Brandon C. Vance, Caitlin M. Quinn, Cong Wang, Dionisios G. Vlachos
Summary: The current methods are not able to handle chlorine-contaminated plastic feedstocks, and the authors propose a two-stage dechlorination-hydrogenolysis (or hydrocracking) upcycling strategy to tackle this problem.
NATURE SUSTAINABILITY
(2023)
Article
Chemistry, Multidisciplinary
Darien K. Nguyen, Vibin Vargheese, Vinson Liao, Panagiotis Dimitrakellis, Sagar Sourav, Weiqing Zheng, Dionisios G. Vlachos
Summary: The study demonstrates that nonthermal, atmospheric He/O-2 plasma (NTAP) is an efficient and controllable method for removing organic ligands like PVP from nanoparticles, without altering the shape and size of the nanoparticles, making it a more efficient alternative to traditional calcination.
Article
Computer Science, Interdisciplinary Applications
Xue Zong, Jonathan Lym, Dionisios G. Vlachos
Summary: DescMAP is a Python-based software that automates the selection of descriptors, the generation of volcano maps, and the identification of active sites for structure-sensitive reactions. It enables quick screening of potential catalysts and can be applied to other complex chemistries.
COMPUTER PHYSICS COMMUNICATIONS
(2023)
Article
Engineering, Chemical
Arnav Mittal, Souryadeep Bhattacharyya, Matthew Marino, Tai-Ying Chen, Pierre Desir, Marianthi Ierapetritou, Dionisios G. Vlachos
Summary: Liquid-liquid microchannels have high mass transfer rates but low throughput. To increase productivity, scaling up the channels by increasing diameter is crucial. However, predicting flow patterns and mass transfer rates with varying diameter while accounting for solvent effects is lacking in the literature. In this study, we develop machine learning models to predict flow patterns and mass transfer rates, considering solvent properties and channel diameter, using experimental and computational fluid dynamics data combined with literature-mined data.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Physical
Alfred Worrad, Sagar Sourav, Stavros Caratzoulas, Dionisios G. Vlachos
Summary: The structure of supported MoOx/Al2O3 catalysts was investigated using AIMD and DFT. Phase diagrams were computed to understand the hydroxylation coverage under different conditions. The results showed that DFT is a cost-effective method for computing vibrational frequencies under certain hydrated conditions, but is susceptible to errors under dehydrated conditions. The power spectra of individual hydroxyls revealed a strong relationship between OH stretching frequencies and the surrounding coordination environment and MoOx anchoring location.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Cong Wang, Sagar Sourav, Kewei Yu, Yeonsu Kwak, Weiqing Zheng, Dionisios G. Vlachos
Summary: This study successfully electrifies the dry reforming of methane using metal-free doped ceria catalysts and microwave radiation, providing new insights and methods for carbon-free syngas production.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
