Article
Chemistry, Organic
Zhiyong Yin, Daniel Baer, Bertolt Gust, Jeroen S. Dickschat
Summary: This study investigated the substrate scope of nine dehydratases involved in secondary metabolite biosynthesis, in addition to FabZ from fatty acid biosynthesis, using a panel of N-acetylcysteamine (SNAC) thioesters. The best performing enzyme, BorDH2, was used in kinetic resolutions.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Review
Chemistry, Multidisciplinary
Yi Zhang, Hui Cai, Xiuhai Gan, Zhichao Jin
Summary: This paper provides a systematic review of N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions, dynamic kinetic resolutions, and desymmetrization reactions. The content is organized based on the activation modes involved in these transformations. Future advances in this highly active research field are also discussed from the authors' perspectives.
SCIENCE CHINA-CHEMISTRY
(2023)
Article
Chemistry, Organic
Shuang-Liang Liu, Yan Qiao, Yang Wang
Summary: A general mechanistic map has been proposed and studied for NHC-catalyzed transformation reactions of saturated carboxylic anhydrides, predicting the origin of chemo- and stereo-selectivities. The fundamental pathway of this reaction includes processes such as C-O bond cleavage, alpha-H elimination, beta-H elimination, functionalization with benzylidene diketone, acyl migration, aldol addition, catalyst dissociation, and decarboxylation. The chemoselectivities in other pathways and the stereoselectivity-determining step have also been investigated.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Physical
Yang Wang, Yan Qiao, Yu Lan, Donghui Wei
Summary: Using density functional theory, this study investigated the origin of selectivity in the N-heterocyclic carbene-catalyzed reaction and proposed a reaction mechanism, highlighting the important role of NHC in catalysis. The findings provide insights into predicting the chemoselectivity of reactions involving cyclopropane rings.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Inorganic & Nuclear
Konstantin E. Shepelenko, Safarmurod B. Soliev, Alexey S. Galushko, Victor M. Chernyshev, Valentine P. Ananikov
Summary: The dynamic nature of the metal-NHC bond plays a crucial role in changing the nature of catalytically active sites, with Pd/NHC complexes showing effective catalysis and Ni/NHC complexes leading to deactivation. The cleavage of the metal-NHC bond should be considered for the efficient choice and optimization of catalytic systems for arylation reactions.
INORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Multidisciplinary
Jing Luo, Li-Li Han, Kuohong Chen, Jinshuai Song, Donghui Wei
Summary: The possible mechanisms and origin of regioselectivity in the N-heterocyclic carbene (NHC)-catalyzed double acylation reaction of aromatic 1,2-diketones with alpha,beta-unsaturated ketones have been theoretically studied using density functional theory. Two regioselective pathways have been identified, with the pathway to the acetyl carbon confirmed as the main one. The rate-determining step was found to be the Michael addition forming a C-C bond.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Physical
Yan Li, Zhilin Li, Zhiqiang Zhang
Summary: The study investigated the mechanism and stereoselectivity of an N-heterocyclic carbene (NHC)-catalyzed annulation reaction. Results showed that Michael addition is the key step controlling stereoselectivity, with noncovalent interactions playing an important role.
MOLECULAR CATALYSIS
(2021)
Article
Chemistry, Organic
Yuan-Yuan Gao, Chun-Lin Zhang, Lei Dai, You-Feng Han, Song Ye
Summary: The unprecedented dynamic kinetic resolution (DKR) of hemiaminals without alpha-hydrogen was developed via N-heterocyclic carbene catalyzed O-acylation, resulting in high yields of esters with good to high enantioselectivities.
Article
Chemistry, Organic
Jiaming Zhang, Qinyu Qiao, Zhoujie Wu, Zhou Pang, Qianqian Shi, Yanyan Wang, Yan Qiao, Donghui Wei
Summary: Using density functional theory calculations, the fundamental pathway for the NHC-catalyzed synthesis of axially chiral benzothiophene-fused biaryls was investigated. The results provide insights into the formation mechanism of key intermediates and explain the observed chemo- and stereoselectivities.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Physical
Martin Soto, Irene Sanz-Machin, Humberto Rodriguez-Solla, Vicente Gotor-Fernandez
Summary: This study focused on the synthesis of a series of trans-flavan-4-ols with different substitution patterns in the aromatic ring and explored the potential of using lipases as biocatalysts for selective acylation reactions. By screening lipases and optimizing reaction conditions, highly asymmetric transformations of 2-phenylchroman-4-ol were achieved, demonstrating the efficiency of AK lipase from Pseudomonas fluorescens in this process.
Article
Chemistry, Physical
Yan Li, Zhiyi Song, Zhiqiang Zhang
Summary: In this study, we investigated the mechanism and key factors controlling the regio- and stereoselectivity of the [3 + 3] cycloaddition reaction between an ester and a benzofuran mediated by a chiral NHC catalyst. The results showed that carbon-carbon bond formation is the determining factor for the reaction's stereoselectivity. Non-covalent interaction and global reactivity index analyses revealed the mechanism of regioselectivity.
MOLECULAR CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Nikki J. Wolford, Salvador B. Munoz, Peter G. N. Neate, William W. Brennessel, Michael L. Neidig
Summary: The use of N-heterocyclic carbene (NHC) ligands in iron-catalyzed organic transformations is crucial to understanding the reduction events and reactivity, with different types of NHCs impacting the iron speciation and reactivity.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Biotechnology & Applied Microbiology
David Alexander Mitchell, Nadia Krieger
Summary: This study reparameterized the expressions for the relative rates of reaction of enantiomers in kinetic resolutions, making them easier to relate to the reaction mechanism.
BIOCHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Organic
Xinhua Jia, Qiong Wang, Jianbiao Liu, Wenjuan Wang, Chuanzhi Sun, Fang Huang, Chong Yang, Dezhan Chen
Summary: The mechanism of N-heterocyclic carbene (NHC)-Cu-catalyzed selective allylation of N-benzylideneaniline with three allyl bromides was investigated using density functional theory (DFT) calculations. The results revealed a unique B(pin)-mediated Cu/B rearrangement mechanism, which is important for the rational design of reaction systems.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Anton Axelsson, Mathias Westerlund, Savannah C. Zacharias, August Runemark, Matti Haukka, Henrik Sunden
Summary: An oxidative NHC-catalyzed kinetic resolution of racemic mixtures was developed to generate tricyclic dihydropyranones with excellent dia- and enantioselectivity. Mechanistic studies revealed that the rate-determining step is the formation of the Breslow intermediate, while the selectivity determining step occurs later in the mechanism. This methodology allows for rapid synthesis of complex structures in a single step.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Drew P. Harding, Laura J. Kingsley, Glen Spraggon, Steven E. Wheeler
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2020)
Article
Chemistry, Multidisciplinary
Victoria M. Ingman, Anthony J. Schaefer, Laura R. Andreola, Steven E. Wheeler
Summary: With the advancement of computational quantum chemistry tools, larger and more complex molecular systems can now be studied. However, the analysis of these systems requires a large number of computations, making manual processes tedious and error-prone. To address this issue, a suite of free, open-source tools has been developed to automate quantum chemistry workflows.
WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Chendan Zhu, Francesca Mandrelli, Hui Zhou, Rajat Maji, Benjamin List
Summary: A scalable catalytic approach for enantiopure and unmodified beta(2)-amino acids was developed, utilizing a confined imidodiphosphorimidate (IDPi) catalyst and a silylated aminomethyl ether. Both aromatic and aliphatic beta(2)-amino acids can be obtained in high yields, purity, and enantioselectivity. Mechanistic studies suggest the reaction proceeds via silylium-based asymmetric counteranion-directed catalysis (Si-ACDC) with a proposed transition state for explaining enantioselectivity based on density functional theory calculations.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Anthony J. Schaefer, Victoria M. Ingman, Steven E. Wheeler
Summary: The SEQCROW bundle for UCSF ChimeraX offers advanced structure editing capabilities and quantum chemistry utilities specifically designed for complex organic and organometallic compounds. Users can efficiently generate publication-quality molecular structure figures, visualize vibrational modes, compute molecular descriptors, and manage computational tasks with this plugin.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Tynchtyk Amatov, Nobuya Tsuji, Rajat Maji, Lucas Schreyer, Hui Zhou, Markus Leutzsch, Benjamin List
Summary: This study reports two highly enantioselective and diastereoselective catalytic Mukaiyama aldol reactions, which directly deliver valuable silyl protected propionaldehyde aldols with control over stereochemistry. A single atom modification in the catalyst core leads to a dramatic switch in enantioselectivity of the aldehyde through unconventional C-H hydrogen bonding interactions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Review
Chemistry, Multidisciplinary
Jennifer L. Kennemur, Rajat Maji, Manuel J. Scharf, Benjamin List
Summary: Asymmetric hydroalkoxylation is an efficient synthetic strategy, but catalytic enantioselective additions of alcohols across a C-C multiple bond are particularly underdeveloped. Recent innovations have driven significant progress in this field.
Article
Chemistry, Multidisciplinary
C. David Diaz-Oviedo, Rajat Maji, Benjamin List
Summary: In this study, an enantioselective intermolecular Prins reaction of styrenes and paraformaldehyde was achieved using confined imino-imidodiphosphate (iIDP) Bronsted acid catalysts, leading to the formation of valuable synthetic building blocks, 1,3-dioxanes. The enantioenriched 1,3-dioxanes can be transformed into optically active 1,3-diols, which are important intermediates in organic synthesis.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Santanu Ghosh, Johannes Eike Erchinger, Rajat Maji, Benjamin List
Summary: A catalytic enantioselective Diels-Alder reaction has been developed for the synthesis of spirocycles containing highly congested quaternary stereogenic centers. The obtained products are utilized in the concise total and formal syntheses of several sesquiterpenes. The selectivity and regioselectivity of the reaction are controlled by strongly acidic and confined imidodiphosphorimidate catalysts.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Jie Ouyang, Rajat Maji, Markus Leutzsch, Benjamin Mitschke, Benjamin List
Summary: Here, we report the design of a highly enantioselective, catalytic (4 + 3) cycloaddition reaction enabled by strong and confined IDPi Lewis acids. This reaction allows the synthesis of novel compounds with multiple stereocenters from gem-dialkyl 2-indolylalcohols and dienolsilanes. The method exhibits broad substrate scope and versatile downstream chemical modifications. Density functional theory-supported mechanistic studies reveal the significance of the in-situ generated silylium species in an overall concerted yet asynchronous cycloaddition.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Rajat Maji, Santanu Ghosh, Oleg Grossmann, Pinglu Zhang, Markus Leutzsch, Nobuya Tsuji, Benjamin List
Summary: In this study, a catalytic asymmetric hydrolactonization using a confined imidodiphosphorimidate (IDPi) Bronsted acid catalyst is reported. The method is simple, scalable, and compatible with a wide variety of substrates. The mechanism and enantioselectivity of this reaction are elucidated through in-depth physicochemical and DFT analyses.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Review
Chemistry, Multidisciplinary
Rajat Maji, Sharath Chandra Mallojjala, Steven E. Wheeler
Summary: This article introduces the importance of electrostatic interactions in catalytic systems and the application of computational chemistry methods in studying these interactions. The author reveals the role of electrostatic interactions in reaction mechanisms and selectivity through quantum chemical computations, using asymmetric organocatalysis as specific examples.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
William J. Mullin, Peter Mueller, Anthony J. Schaefer, Elisa Guzman, Steven E. Wheeler, Samuel W. Thomas
Summary: This study investigates the stacking interactions between aromatic rings and heterocycles, revealing that fluorinated side-chains and electron-rich units have interactions in the solid state, while electron-deficient units are incompatible. These interactions play a significant role in compound stability.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Chemistry, Organic
Laura R. Andreola, Steven E. Wheeler
Summary: Automated transition state structure computations have revealed unexpected conformations of the key stereodifferentiating benzyl group in a recently reported Pd-catalysed conjugated addition reaction. The stereoselectivity of this reaction is determined by favorable non-covalent contacts between the benzyl group and the substrates, as well as torsional strain in the primary transition state structure.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Organic
Ian S. Taschner, Tia L. Walker, Sharath M. Chandra, Briana R. Schrage, Christopher J. Ziegler, Xinfeng Gao, Steven E. Wheeler
ORGANIC CHEMISTRY FRONTIERS
(2020)
