1
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Brion A, Martini V, Lombard M, Retailleau P, Della Ca' N, Neuville L, Masson G. Phenolic Dienes as Highly Selective Dienophiles in the Asymmetric Organocatalyzed Three-Component Vinylogous Povarov Reaction. J Org Chem 2024. [PMID: 39152912 DOI: 10.1021/acs.joc.4c01239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/19/2024]
Abstract
Our study presents a novel enantioselective route for the synthesis of 1,2,3,4-tetrahydroquinolines via a chiral phosphoric acid-catalyzed three-component Povarov reaction, employing phenolic dienes as dienophiles. This approach produces a diverse array of 2,3,4-trisubstituted tetrahydroquinolines, each featuring a styryl group at position 4, in high yields with excellent regio-, diastereo-, and enantioselectivities (>95:5 dr and up to >99% ee).
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Affiliation(s)
- Aurélien Brion
- Institut de Chimie des Substances Naturelles (ICSN), CNRS UPR 2301, Université Paris-Saclay, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
| | - Vittoria Martini
- Institut de Chimie des Substances Naturelles (ICSN), CNRS UPR 2301, Université Paris-Saclay, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
- SynCat Lab, Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
| | - Marine Lombard
- Institut de Chimie des Substances Naturelles (ICSN), CNRS UPR 2301, Université Paris-Saclay, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
| | - Pascal Retailleau
- Institut de Chimie des Substances Naturelles (ICSN), CNRS UPR 2301, Université Paris-Saclay, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
| | - Nicola Della Ca'
- SynCat Lab, Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
| | - Luc Neuville
- Institut de Chimie des Substances Naturelles (ICSN), CNRS UPR 2301, Université Paris-Saclay, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
- HitCat, Seqens-CNRS Joint Laboratory, Seqens'Lab, 8 Rue de Rouen, 78440 Porcheville, France
| | - Géraldine Masson
- Institut de Chimie des Substances Naturelles (ICSN), CNRS UPR 2301, Université Paris-Saclay, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
- HitCat, Seqens-CNRS Joint Laboratory, Seqens'Lab, 8 Rue de Rouen, 78440 Porcheville, France
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2
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Peck A, Sun M, Howard E, Hong X, Brewer M. Origins of Diastereoselectivity in the Addition of Enoxysilanes to Vinyl Diazonium Salts. J Org Chem 2024; 89:11019-11025. [PMID: 39002159 DOI: 10.1021/acs.joc.4c00874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/15/2024]
Abstract
The addition of enoxysilanes to vinyl diazonium ions occurs with varying levels of diastereoselectivity. To understand the origins of the stereoselectivity, we studied these transformations using density functional theory (DFT) calculations. The selectivity stems from a stabilizing cation-π interaction that orients the nucleophile and the diazonium ion.
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Affiliation(s)
- Avery Peck
- Department of Chemistry, University of Vermont, 82 University Place, Burlington, Vermont 05495, United States
| | - Manman Sun
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China
- Advanced Research Institute and School of Pharmaceutical Science, Taizhou University, Jiaojiang, Zhejiang 318000, China
| | - Evan Howard
- Department of Chemistry, University of Vermont, 82 University Place, Burlington, Vermont 05495, United States
| | - Xin Hong
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China
- Beijing National Laboratory for Molecular Sciences, Zhongguancun North First Street No. 2, Beijing 100190, China
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China
| | - Matthias Brewer
- Department of Chemistry, University of Vermont, 82 University Place, Burlington, Vermont 05495, United States
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3
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Renningholtz T, Lim ERX, James MJ, Trujillo C. Computational methods for investigating organic radical species. Org Biomol Chem 2024. [PMID: 39012651 DOI: 10.1039/d4ob00532e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
Computational analysis of organic radical species presents significant challenges. This study compares the efficacy of various DFT and wavefunction methods in predicting radical stabilisation energies, bond dissociation energies, and redox potentials for organic radicals. The hybrid meta-GGA M062X-D3(0), and the range-separated hybrids ωB97M-V and ωB97M-D3(BJ) emerged as the most reliable functionals, consistently providing accurate predictions across different basis sets including 6-311G**, cc-pVTZ, and def2-TZVP.
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Affiliation(s)
- Tim Renningholtz
- The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Ethan R X Lim
- The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Michael J James
- The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Cristina Trujillo
- The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
- TBSI - School of Chemistry, The University of Dublin, Trinity College, D02 R590 Dublin 2, Ireland
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4
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Guo Y, He L, Ding Y, Kloo L, Pantazis DA, Messinger J, Sun L. Closing Kok's cycle of nature's water oxidation catalysis. Nat Commun 2024; 15:5982. [PMID: 39013902 PMCID: PMC11252165 DOI: 10.1038/s41467-024-50210-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 07/03/2024] [Indexed: 07/18/2024] Open
Abstract
The Mn4CaO5(6) cluster in photosystem II catalyzes water splitting through the Si state cycle (i = 0-4). Molecular O2 is formed and the natural catalyst is reset during the final S3 → (S4) → S0 transition. Only recently experimental breakthroughs have emerged for this transition but without explicit information on the S0-state reconstitution, thus the progression after O2 release remains elusive. In this report, our molecular dynamics simulations combined with density functional calculations suggest a likely missing link for closing the cycle, i.e., restoring the first catalytic state. Specifically, the formation of closed-cubane intermediates with all hexa-coordinate Mn is observed, which would undergo proton release, water dissociation, and ligand transfer to produce the open-cubane structure of the S0 state. Thereby, we theoretically identify the previously unknown structural isomerism in the S0 state that acts as the origin of the proposed structural flexibility prevailing in the cycle, which may be functionally important for nature's water oxidation catalysis.
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Affiliation(s)
- Yu Guo
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science, Westlake University, Hangzhou, 310024, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou, 310024, China
| | - Lanlan He
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science, Westlake University, Hangzhou, 310024, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou, 310024, China
| | - Yunxuan Ding
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science, Westlake University, Hangzhou, 310024, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou, 310024, China
| | - Lars Kloo
- Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, SE-10044, Stockholm, Sweden
| | - Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr, 45470, Germany
| | - Johannes Messinger
- Department of Plant Physiology, Umeå University, Linnaeus väg 6 (KBC huset), SE-90187, Umeå, Sweden
- Molecular Biomimetics, Department of Chemistry - Ångström Laboratory, Uppsala University, SE-75120, Uppsala, Sweden
| | - Licheng Sun
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science, Westlake University, Hangzhou, 310024, China.
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou, 310024, China.
- Division of Solar Energy Conversion and Catalysis at Westlake University, Zhejiang Baima Lake Laboratory Co., Ltd., Hangzhou, 310000, Zhejiang, China.
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5
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Yuan S, Han X, Zhang J, Xie Z, Fan C, Xiao Y, Gao YQ, Yang YI. Generating High-Precision Force Fields for Molecular Dynamics Simulations to Study Chemical Reaction Mechanisms Using Molecular Configuration Transformer. J Phys Chem A 2024; 128:4378-4390. [PMID: 38759697 DOI: 10.1021/acs.jpca.4c01267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/19/2024]
Abstract
Theoretical studies on chemical reaction mechanisms have been crucial in organic chemistry. Traditionally, calculating the manually constructed molecular conformations of transition states for chemical reactions using quantum chemical calculations is the most commonly used method. However, this way is heavily dependent on individual experience and chemical intuition. In our previous study, we proposed a research paradigm that used enhanced sampling in molecular dynamics simulations to study chemical reactions. This approach can directly simulate the entire process of a chemical reaction. However, the computational speed limited the use of high-precision potential energy functions for simulations. To address this issue, we presented a scheme for training high-precision force fields for molecular modeling using a previously developed graph-neural-network-based molecular model, molecular configuration transformer. This potential energy function allowed for highly accurate simulations at a low computational cost, leading to more precise calculations of the mechanism of chemical reactions. We applied this approach to study a Claisen rearrangement reaction and a carbonyl insertion reaction catalyzed by manganese.
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Affiliation(s)
- Sihao Yuan
- Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen 518132, China
| | - Xu Han
- Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Jun Zhang
- Changping Laboratory, Beijing 102200, China
| | - Zhaoxin Xie
- Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen 518132, China
| | - Cheng Fan
- Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen 518132, China
| | - Yunlong Xiao
- Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Yi Qin Gao
- Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen 518132, China
- Changping Laboratory, Beijing 102200, China
| | - Yi Isaac Yang
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen 518132, China
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6
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Huang GT, Yu JSK. Catalytic role of the enol ether intermediate in the intramolecular Stetter reaction: a computational perspective. Phys Chem Chem Phys 2024; 26:11833-11853. [PMID: 38567403 DOI: 10.1039/d3cp06051a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The intramolecular Stetter reaction catalyzed by a carbene is investigated by density functional theory (DFT) calculations and kinetic simulations. Catalyst 1 first reacts with aldehyde 2 to give the primary adduct (PA). The PA undergoes the intramolecular oxa-Michael reaction to irreversibly generate enol ether intermediate 9. The conversion of the enol ether to the Breslow intermediate (BI) requires the assistance of a base such as the PA. The next step involves formation of a carbon-carbon bond through the Michael addition, and expulsion of the catalyst generates the Stetter product 7. Calculations show that the catalytic cycle is composed of two irreversible processes: the first one involves the exergonic formation of the enol ether intermediate, while the second one is the conversion of the enol ether to the final product. Kinetic simulations using initial concentrations of [1]0 = 0.005 M and [2]0 = 0.025 M demonstrate that under a steady-state condition, 35% of the catalyst rests on the state of the enol ether (0.0018 M). The catalyst resting state therefore consists of the unbound form (the free catalyst) and its bound form (the enol ether species). According to variable time normalization analysis, the reaction exhibits a second-order dependence (first order in catalyst and first order in substrate), which agrees with experiments. The oxa-Michael reaction to form the enol ether is identified to be turnover limiting in the intramolecular Stetter reaction, which rationalizes the observed electronic effect of the Michael acceptor on the reactivity, as well as the measured isotope effect with respect to the aldehydic proton/deuteron. The base that participates in the BI formation has a significant effect on the build-up of the resting state 9 and the active catalyst concentration. In addition, the thermodynamic stability of the enol ether is found to depend on the tether length between the aromatic aldehyde and the Michael acceptor, as well as the chemical nature of the carbene catalyst. The favorability for the oxa-Michael reaction is therefore suggested to govern the reactivity of the intramolecular Stetter transformation.
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Affiliation(s)
- Gou-Tao Huang
- Department of Biological Science and Technology, National Yang Ming Chiao Tung University, Hsinchu City 300, Taiwan.
| | - Jen-Shiang K Yu
- Department of Biological Science and Technology, National Yang Ming Chiao Tung University, Hsinchu City 300, Taiwan.
- Institute of Bioinformatics and Systems Biology, National Yang Ming Chiao Tung University, Hsinchu City 300, Taiwan
- Center for Intelligent Drug Systems and Smart Bio-devices (IDS2B), National Yang Ming Chiao Tung University, Hsinchu City 300, Taiwan
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7
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Hou XX, Wei D. Mechanism and Origin of Stereoselectivity for the NHC-Catalyzed Desymmetrization Reaction for the Synthesis of Axially Chiral Biaryl Aldehydes. J Org Chem 2024; 89:3133-3142. [PMID: 38359780 DOI: 10.1021/acs.joc.3c02575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Organocatalytic desymmetrization reaction is a powerful tool for constructing axial chirality, but the theoretical study on the origin of stereoselectivity still lags behind even now. In this work, the N-heterocyclic carbene (NHC)-catalyzed desymmetrization reaction of biaryl frameworks for the synthesis of axially chiral aldehydes has been selected and theoretically investigated by using density functional theory (DFT). The fundamental pathway involves several steps, i.e., desymmetrization, formation of Breslow oxidation, esterification, and NHC regeneration. The desymmetrization and formation of Breslow processes have been identified as stereoselectivity-determining and rate-determining steps. Further weak interaction analyses proved that the C-H···O hydrogen bond and C-H···π interactions are responsible for the stability of the key stereoselective desymmetrization transition states. This research contributes to understanding the nature of NHC-catalyzed desymmetrization reactions for the synthesis of axially chiral compounds.
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Affiliation(s)
- Xiao-Xiao Hou
- College of Chemistry, and Institute of Green Catalysis, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, Henan, P. R. China
| | - Donghui Wei
- College of Chemistry, and Institute of Green Catalysis, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, Henan, P. R. China
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8
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Yan X, Du M, Li J, Xue Y, Wu Y, Zhang H, Wang X, Xu D. A theoretical study of the mechanism of cationic polymerization of isobutylene catalysed by EtAlCl 2/ t-BuCl with bis(2-chloroethyl)ether in hexanes. Phys Chem Chem Phys 2024; 26:6763-6773. [PMID: 38323624 DOI: 10.1039/d3cp05337g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
The mechanism of cationic polymerization of isobutylene catalyzed by t-BuCl/ethylaluminum dichloride (EADC) combined with bis(2-chloroethyl)ether (CEE) in n-hexane solvent has been investigated using ab initio molecular dynamics (AIMD) and metadynamics (MTD) simulations. The results indicated that the polyisobutylene (PIB) initiation stage involves a clear two-step mechanism. Calculation of the free energy landscapes of the other two ether reactions reveals that the energy barriers of diisopropyl ether (i-Pr2O) and 2-chloroethyl ethyl ether (CEEE) are much higher than those of CEE, which is consistent with the experimental results. During the chain propagation phase, the required free energy barrier gradually decreases and tends to reach equilibrium as the chain length increases. Finally, the oxonium mechanism during the chain initiation stage was investigated by calculating the 1H NMR spectra and MTD simulation. Our calculations can confirm that the existence of tert-butyloxonium ions during the reaction is possible. Their contribution to the whole reaction is further discussed.
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Affiliation(s)
- Xinrong Yan
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China.
| | - Meng Du
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China.
| | - Jiwei Li
- Chengdu Migersi Medical Technology Co., Ltd, Chengdu, Sichuan, 610219, P. R. China
| | - Ying Xue
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China.
| | - Yibo Wu
- The College of New Materials and Chemical Engineering, Beijing Key Lab of Special Elastomer Composite Materials, Beijing Institute of Petrochemical Technology, Beijing, 102617, P. R. China
| | - Hao Zhang
- Chengdu Migersi Medical Technology Co., Ltd, Chengdu, Sichuan, 610219, P. R. China
| | - Xin Wang
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China.
| | - Dingguo Xu
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China.
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9
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Kucharski DJ, Suchanek R, Kowalczyk R, Boratyński PJ. Development of Mefloquine-Based Bifunctional Secondary Amine Organocatalysts for Enantioselective Michael and Friedel-Crafts Reactions. J Org Chem 2024; 89:111-123. [PMID: 38069836 DOI: 10.1021/acs.joc.3c01791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
The chiral framework based on 11-aminomefloquine has been utilized for the first time to construct bifunctional organocatalysts. These catalysts demonstrate high enantioselectivity in both Michael additions and Friedel-Crafts reactions across a variety of substrates, achieving up to >99% ee. The distinctive feature is the incorporation of a secondary amine group, offering unique tight hydrogen-bonding capabilities in the protonated state, as supported by DFT computation. The diversity of these organocatalysts suggests their broad applicability across multiple reaction classes.
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Affiliation(s)
- Dawid J Kucharski
- Department of Organic and Medicinal Chemistry, Wrocław University of Technology, Wyb. Wyspiańskiego 26, Wrocław 50-370, Poland
| | - Radosław Suchanek
- Department of Organic and Medicinal Chemistry, Wrocław University of Technology, Wyb. Wyspiańskiego 26, Wrocław 50-370, Poland
| | - Rafał Kowalczyk
- Department of Bioorganic Chemistry Wrocław University of Technology, Wyb. Wyspiańskiego 26, Wrocław 50-370, Poland
| | - Przemysław J Boratyński
- Department of Organic and Medicinal Chemistry, Wrocław University of Technology, Wyb. Wyspiańskiego 26, Wrocław 50-370, Poland
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10
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Hayashi H, Maeda S, Mita T. Quantum chemical calculations for reaction prediction in the development of synthetic methodologies. Chem Sci 2023; 14:11601-11616. [PMID: 37920348 PMCID: PMC10619630 DOI: 10.1039/d3sc03319h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 09/29/2023] [Indexed: 11/04/2023] Open
Abstract
Quantum chemical calculations have been used in the development of synthetic methodologies to analyze the reaction mechanisms of the developed reactions. Their ability to estimate chemical reaction pathways, including transition state energies and connected equilibria, has led researchers to embrace their use in predicting unknown reactions. This perspective highlights strategies that leverage quantum chemical calculations for the prediction of reactions in the discovery of new methodologies. Selected examples demonstrate how computation has driven the development of unknown reactions, catalyst design, and the exploration of synthetic routes to complex molecules prior to often laborious, costly, and time-consuming experimental investigations.
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Affiliation(s)
- Hiroki Hayashi
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University Kita 21, Nishi 10, Kita-ku Sapporo Hokkaido 001-0021 Japan
- JST-ERATO, Maeda Artificial Intelligence in Chemical Reaction Design and Discovery Project Kita 10, Nishi 8, Kita-ku Sapporo Hokkaido 060-0810 Japan
| | - Satoshi Maeda
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University Kita 21, Nishi 10, Kita-ku Sapporo Hokkaido 001-0021 Japan
- JST-ERATO, Maeda Artificial Intelligence in Chemical Reaction Design and Discovery Project Kita 10, Nishi 8, Kita-ku Sapporo Hokkaido 060-0810 Japan
- Department of Chemistry, Faculty of Science, Hokkaido University Kita 10, Nishi 8, Kita-ku Sapporo Hokkaido 060-0810 Japan
| | - Tsuyoshi Mita
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University Kita 21, Nishi 10, Kita-ku Sapporo Hokkaido 001-0021 Japan
- JST-ERATO, Maeda Artificial Intelligence in Chemical Reaction Design and Discovery Project Kita 10, Nishi 8, Kita-ku Sapporo Hokkaido 060-0810 Japan
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11
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Harden I, Neese F, Bistoni G. Dimerization of confined Brønsted acids in enantioselective organocatalytic reactions. Chem Sci 2023; 14:10580-10590. [PMID: 37799993 PMCID: PMC10548523 DOI: 10.1039/d3sc03769j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 09/08/2023] [Indexed: 10/07/2023] Open
Abstract
The formation of Brønsted acid aggregates in the course of asymmetric organocatalytic reactions is often overlooked in mechanistic studies, even though it might have a deep impact on the stereo-controlling factors of the transformations. In this work, we shed light on the influence of the catalyst structure and reaction conditions on the spontaneity of the aggregation process for popular chiral organocatalysts derived from phosphoric acids using high-level quantum mechanical calculations. Our study encompasses small and sterically unhindered chiral phosphoric acids as well as large and "confined" imidodiphosphates and imidodiphosphorimidates. These systems have recently proven particularly effective in promoting a large number of highly relevant asymmetric transformations. While cooperative catalytic effects of sterically less hindered chiral phosphoric acid catalysts are well appreciated in literature, it is found that the formation of catalyst dimers in solution is possible for both standard and confined catalysts. The spontaneity of the aggregation process depends on reaction conditions like solvent polarity, polarizability, temperature, the nature of the interaction with the substrate, as well as the catalyst architecture. Finally, it is shown that, at low temperatures (153 K), the aggregation process can profoundly influence the reaction kinetics and selectivity.
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Affiliation(s)
- Ingolf Harden
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm Platz 1 45470 Mülheim an der Ruhr Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm Platz 1 45470 Mülheim an der Ruhr Germany
| | - Giovanni Bistoni
- Department of Chemistry, Biology and Biotechnology, University of Perugia Via Elce di Sotto, 8 06123 Perugia Italy
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12
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Hussein AA, Ariffin A. Remote Steric and Electronic Effects of N-Heterocyclic Carbene Ligands on Alkene Reactivity and Regioselectivity toward Hydrocupration Reactions: The Role of Expanded-Ring N-Heterocyclic Carbenes. J Org Chem 2023; 88:13009-13021. [PMID: 37649423 DOI: 10.1021/acs.joc.3c01121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
The remote groups in N-heterocyclic carbene (NHC) ligands have a significant influence on metal-catalyzed reactions. We examine how remote bulkiness, electronic groups, and expanded-ring NHCs (ER-NHCs) influence alkene reactivity and regioselectivity toward hydrocupration using density functional theory calculations. The impact of remote steric bulkiness on the Cu-H insertion rate is analyzed, revealing a strong correlation between the steric substituent constant and rate ratio, where a bulky group increases the rate due to reduced steric effects in the transition state (TS). The steric properties of the examined catalysts (with a remote group R2 = CPh3, CHPh2, CH2Ph, CH3, and H) and their corresponding TSs are found to be modulated greatly by the remote steric substitution group and the ring size of the NHC ligand. Enhanced bulkiness enhances the nucleophilic Cu-H moiety. The remote electronic groups have a smaller impact on insertion barrier compared to that of steric hindrance. Furthermore, ER-NHC exploration indicates that NHCs with over five-membered rings have a significantly negative influence on the reaction rate. Finally, with a highly bulky group (R2 = CPh3), anti-Markovnikov insertion preference is attributed to high interaction energy and improved steric properties. Overall, our findings here provide valuable insights for the development of a more effective catalyst in metal-catalyzed reactions.
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Affiliation(s)
- Aqeel A Hussein
- Department of Medical Laboratory Science, College of Science, Komar University of Science and Technology, Sulaymaniyah, Kurdistan Region 46001, Iraq
- Department of Biology, College of Science, Al-Qasim Green University, Al-Qassim, Babylon 51013, Iraq
| | - Azhar Ariffin
- Department of Chemistry, Faculty of Science, University Malaya, Kuala Lumpur 50603, Malaysia
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13
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Reid JP, Betinol IO, Kuang Y. Mechanism to model: a physical organic chemistry approach to reaction prediction. Chem Commun (Camb) 2023; 59:10711-10721. [PMID: 37552047 DOI: 10.1039/d3cc03229a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/09/2023]
Abstract
The application of mechanistic generalizations is at the core of chemical reaction development and application. These strategies are rooted in physical organic chemistry where mechanistic understandings can be derived from one reaction and applied to explain another. Over time these techniques have evolved from rationalizing observed outcomes to leading experimental design through reaction prediction. In parallel, significant progression in asymmetric organocatalysis has expanded the reach of chiral transfer to new reactions with increased efficiency. However, the complex and diverse catalyst structures applied in this arena have rendered the generalization of asymmetric catalytic processes to be exceptionally challenging. Recognizing this, a portion of our research has been focused on understanding the transferability of chemical observations between similar reactions and exploiting this phenomenon as a platform for prediction. Through these experiences, we have relied on a working knowledge of reaction mechanism to guide the development and application of our models which have been advanced from simple qualitative rules to large statistical models for quantitative predictions. In this feature article, we describe the models acquired to generalize organocatalytic reaction mechanisms and demonstrate their use as a powerful approach for accelerating enantioselective synthesis.
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Affiliation(s)
- Jolene P Reid
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, V6T 1Z1, Canada.
| | - Isaiah O Betinol
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, V6T 1Z1, Canada.
| | - Yutao Kuang
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, V6T 1Z1, Canada.
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14
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Guan J, Chen J, Luo Y, Guo L, Zhang W. Copper-Catalyzed Chemoselective Asymmetric Hydrogenation of C=O Bonds of Exocyclic α,β-Unsaturated Pentanones. Angew Chem Int Ed Engl 2023; 62:e202306380. [PMID: 37307027 DOI: 10.1002/anie.202306380] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 06/11/2023] [Accepted: 06/12/2023] [Indexed: 06/13/2023]
Abstract
A highly chemoselective earth-abundant transition metal copper catalyzed asymmetric hydrogenation of C=O bonds of exocyclic α,β-unsaturated pentanones was realized using H2 . The desired products were obtained with up to 99 % yield and 96 % ee (enantiomeric excess) (99 % ee, after recrystallization). The corresponding chiral exocyclic allylic pentanol products can be converted into several bioactive molecules. The hydrogenation mechanism was investigated via deuterium-labelling experiments and control experiments, which indicate that the keto-enol isomerization rate of the substrate is faster than that of the hydrogenation and also show that the Cu-H complex can only catalyze chemoselectively the asymmetric reduction of the carbonyl group. Computational results indicate that the multiple attractive dispersion interactions (MADI effect) between the catalyst with bulky substituents and substrate play important roles which stabilize the transition states and reduce the generation of by-products.
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Affiliation(s)
- Jing Guan
- Frontier Science Center for Transformative Molecules, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Jianzhong Chen
- Frontier Science Center for Transformative Molecules, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Yicong Luo
- Frontier Science Center for Transformative Molecules, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Lisen Guo
- Frontier Science Center for Transformative Molecules, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Wanbin Zhang
- Frontier Science Center for Transformative Molecules, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University 800 Dongchuan Road, Shanghai, 200240, P. R. China
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15
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Zhu J, Li J, Zhang L, Sun S, Wang Z, Li X, Yang L, Cheng M, Lin B, Liu Y. Quantum Mechanical Prediction and Experimental Verification of Au(I)-Catalyzed Substitution-Controlled Syntheses of 1 H-Pyrido[4,3- b]indole and Spiro[indoline-3,3'-pyridine] Derivatives. J Org Chem 2023; 88:5483-5496. [PMID: 37043684 DOI: 10.1021/acs.joc.2c03104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
Density functional theory calculations were applied to predict the pathways of gold(I)-catalyzed cycloisomerization of the indole substrates with 1,6-enynes, which were consistent with the ensuing experimental results. The substitution-controlled synthesis led to the formation of 1H-pyrido[4,3-b]indole and spiro[indoline-3,3'-pyridine] derivatives in a tunable way. The reactions had good functional group tolerances, and a possible mechanism was proposed based on the computational and experimental results.
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Affiliation(s)
- Jiang Zhu
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Jiaji Li
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Lianjie Zhang
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Shitao Sun
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Zhaobo Wang
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Xiang Li
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Lu Yang
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Maosheng Cheng
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Bin Lin
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Yongxiang Liu
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
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16
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Zheng H, Cai L, Pan M, Uyanik M, Ishihara K, Xue XS. Catalyst-Substrate Helical Character Matching Determines the Enantioselectivity in the Ishihara-Type Iodoarenes Catalyzed Asymmetric Kita-Dearomative Spirolactonization. J Am Chem Soc 2023; 145:7301-7312. [PMID: 36940192 DOI: 10.1021/jacs.2c13295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2023]
Abstract
Catalyst design has traditionally focused on rigid structural elements to prevent conformational flexibility. Ishihara's elegant design of conformationally flexible C2-symmetric iodoarenes, a new class of privileged organocatalysts, for the catalytic asymmetric dearomatization (CADA) of naphthols is a notable exception. Despite the widespread use of the Ishihara catalysts for CADAs, the reaction mechanism remains the subject of debate, and the mode of asymmetric induction has not been well established. Here, we report an in-depth computational investigation of three possible mechanisms in the literature. Our results, however, reveal that this reaction is best rationalized by a fourth mechanism called "proton-transfer-coupled-dearomatization (PTCD)", which is predicted to be strongly favored over other competing pathways. The PTCD mechanism is consistent with a control experiment and further validated by applying it to rationalize the enantioselectivities. Oxidation of the flexible I(I) catalyst to catalytic active I(III) species induces a defined C2-symmetric helical chiral environment with a delicate balance between flexibility and rigidity. A match/mismatch effect between the active catalyst and the substrate's helical shape in the dearomatization transition states was observed. The helical shape match allows the active catalyst to adapt its conformation to maximize attractive noncovalent interactions, including I(III)···O halogen bond, N-H···O hydrogen bond, and π···π stacking, to stabilize the favored transition state. A stereochemical model capable of rationalizing the effect of catalyst structural variation on the enantioselectivities is developed. The present study enriches our understanding of how flexible catalysts achieve high stereoinduction and may serve as an inspiration for the future exploration of conformational flexibility for new catalyst designs.
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Affiliation(s)
- Hanliang Zheng
- Department of Chemistry, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, China
| | - Liu Cai
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Ming Pan
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Muhammet Uyanik
- Graduate School of Engineering, Nagoya University Furocho, Chikusaku, Nagoya 464-8603, Japan
| | - Kazuaki Ishihara
- Graduate School of Engineering, Nagoya University Furocho, Chikusaku, Nagoya 464-8603, Japan
| | - Xiao-Song Xue
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.,School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, 1 Sub-lane Xiangshan, Hangzhou 310024, P. R. China
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17
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Xing S, Ma C, Liu W, Ni SF, Zhu D, Xu LW, Shao X. Lewis Base-Catalyzed Trifluoromethylsulfinylation of Allylic Alcohols: Stability-Oriented Divergent Synthesis. Org Lett 2023; 25:1066-1071. [PMID: 36779962 DOI: 10.1021/acs.orglett.2c04243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
A novel strategy is demonstrated for Lewis base-activated trifluoromethylsulfinylation of allylic alcohols. Controllable synthesis of structurally varied allylic trifluoromethanesulfones via sigmatropic rearrangements was performed, and trifluoromethanesulfinate esters were achieved. This metal-free, catalytic divergent transformation features good functional group tolerance and late-stage modification of bioactive molecules. Mechanistic studies suggested that Lewis bases interact with N-(trifluoromethylsulfinyl)phthalimide to generate an ion pair adduct followed by O-trifluoromethylsulfinylation with allylic alcohols.
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Affiliation(s)
- Shuya Xing
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, Zhejiang, P. R. China
| | - Cheng Ma
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guang-dong Province, Shantou University, Shantou 515063, People's Republic of China
| | - Wen Liu
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, Zhejiang, P. R. China
| | - Shao-Fei Ni
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guang-dong Province, Shantou University, Shantou 515063, People's Republic of China
| | - Dianhu Zhu
- Key Laboratory of Synthetic and Natural Functional Molecules of the Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an 710127, P. R. China
| | - Li-Wen Xu
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, Zhejiang, P. R. China
| | - Xinxin Shao
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, Zhejiang, P. R. China
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18
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Kuang Y, Lai J, Reid JP. Transferrable selectivity profiles enable prediction in synergistic catalyst space. Chem Sci 2023; 14:1885-1895. [PMID: 36819850 PMCID: PMC9931051 DOI: 10.1039/d2sc05974f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 01/10/2023] [Indexed: 01/19/2023] Open
Abstract
Organometallic intermediates participate in many multi-catalytic enantioselective transformations directed by a chiral catalyst, but the requirement of optimizing two catalyst components is a significant barrier to widely adopting this approach for chiral molecule synthesis. Algorithms can potentially accelerate the screening process by developing quantitative structure-function relationships from large experimental datasets. However, the chemical data available in this catalyst space is limited. Herein, we report a data-driven strategy that effectively translates selectivity relationships trained on enantioselectivity outcomes derived from one catalyst reaction systems where an abundance of data exists, to synergistic catalyst space. We describe three case studies involving different modes of catalysis (Brønsted acid, chiral anion, and secondary amine) that substantiate the prospect of this approach to predict and elucidate selectivity in reactions where more than one catalyst is involved. Ultimately, the success in applying our approach to diverse areas of asymmetric catalysis implies that this general workflow should find broad use in the study and development of new enantioselective, multi-catalytic processes.
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Affiliation(s)
- Yutao Kuang
- Department of Chemistry, University of British Columbia 2036 Main Mall, Vancouver British Columbia V6T 1Z1 Canada
| | - Junshan Lai
- Department of Chemistry, University of British Columbia 2036 Main Mall, Vancouver British Columbia V6T 1Z1 Canada
| | - Jolene P. Reid
- Department of Chemistry, University of British Columbia2036 Main Mall, VancouverBritish ColumbiaV6T 1Z1Canada
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19
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Zhang SQ, Xu LC, Li SW, Oliveira JCA, Li X, Ackermann L, Hong X. Bridging Chemical Knowledge and Machine Learning for Performance Prediction of Organic Synthesis. Chemistry 2023; 29:e202202834. [PMID: 36206170 PMCID: PMC10099903 DOI: 10.1002/chem.202202834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Indexed: 11/29/2022]
Abstract
Recent years have witnessed a boom of machine learning (ML) applications in chemistry, which reveals the potential of data-driven prediction of synthesis performance. Digitalization and ML modelling are the key strategies to fully exploit the unique potential within the synergistic interplay between experimental data and the robust prediction of performance and selectivity. A series of exciting studies have demonstrated the importance of chemical knowledge implementation in ML, which improves the model's capability for making predictions that are challenging and often go beyond the abilities of human beings. This Minireview summarizes the cutting-edge embedding techniques and model designs in synthetic performance prediction, elaborating how chemical knowledge can be incorporated into machine learning until June 2022. By merging organic synthesis tactics and chemical informatics, we hope this Review can provide a guide map and intrigue chemists to revisit the digitalization and computerization of organic chemistry principles.
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Affiliation(s)
- Shuo-Qing Zhang
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China
| | - Li-Cheng Xu
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China
| | - Shu-Wen Li
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China
| | - João C A Oliveira
- Institut für Organische und Biomolekulare Chemie, Wöhler Research Institute for Sustainable Chemistry (WISCh), Georg-August-Universität, Tammannstraße 2, 37077, Göttingen, Germany
| | - Xin Li
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China
| | - Lutz Ackermann
- Institut für Organische und Biomolekulare Chemie, Wöhler Research Institute for Sustainable Chemistry (WISCh), Georg-August-Universität, Tammannstraße 2, 37077, Göttingen, Germany
| | - Xin Hong
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China.,Beijing National Laboratory for Molecular Sciences, Zhongguancun North First Street No. 2, Beijing, 100190, P. R. China.,Key Laboratory of Precise Synthesis of, Functional Molecules of Zhejiang Province, School of Science, Westlake University, 18 Shilongshan Road, Hangzhou, 310024, Zhejiang Province, P. R. China
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20
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Georgieva MK, Santos AG. Theoretical Study on Chiral Boron Complex‐Promoted Asymmetric Diels‐Alder Cycloadditions. European J Org Chem 2022. [DOI: 10.1002/ejoc.202201082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Affiliation(s)
- Miglena K. Georgieva
- LAQV-REQUIMTE, Department of Chemistry NOVA School of Science and Technology Universidade Nova de Lisboa 2829-516 Caparica Portugal
| | - A. Gil Santos
- LAQV-REQUIMTE, Department of Chemistry NOVA School of Science and Technology Universidade Nova de Lisboa 2829-516 Caparica Portugal
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21
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Zhang FR, Cao F, Liu K, He YP, Luo G, Ye ZS. Bifunctional Lewis Base Catalyzed Asymmetric N-Allylic Alkylation of 2-Hydroxypyridines. Org Lett 2022; 24:8603-8608. [DOI: 10.1021/acs.orglett.2c03207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Fei-Ruo Zhang
- Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, P.R. China
| | - Fanshu Cao
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, P.R. China
| | - Kui Liu
- Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, P.R. China
| | - Yi-Ping He
- Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, P.R. China
| | - Gen Luo
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, P.R. China
| | - Zhi-Shi Ye
- Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, P.R. China
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22
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de Lima Lopes Rocha P, dos Santos FM, Pinheiro S, Fiorot RG. Noncovalent interactions as a solution for the metal-free one-pot asymmetric synthesis of (S)-2-aryl-2,3-dihydro-4(1H)-quinolones. J Mol Model 2022; 28:369. [DOI: 10.1007/s00894-022-05361-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 10/20/2022] [Indexed: 11/29/2022]
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23
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Ji P, Liu X, Xu J, Zhang X, Guo J, Chen W, Zhao B. Direct Asymmetric α‐C−H Addition of N‐unprotected Propargylic Amines to Trifluoromethyl Ketones by Carbonyl Catalysis. Angew Chem Int Ed Engl 2022; 61:e202206111. [DOI: 10.1002/anie.202206111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Indexed: 11/05/2022]
Affiliation(s)
- Pengwei Ji
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Xiaopei Liu
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Jiwei Xu
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Xu Zhang
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Jianhua Guo
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Wen‐Wen Chen
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Baoguo Zhao
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
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24
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Ji P, Liu X, Xu J, Zhang X, Guo J, Chen W, Zhao B. Direct Asymmetric α‐C−H Addition of N‐unprotected Propargylic Amines to Trifluoromethyl Ketones by Carbonyl Catalysis. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202206111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Pengwei Ji
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Xiaopei Liu
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Jiwei Xu
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Xu Zhang
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Jianhua Guo
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Wen‐Wen Chen
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
| | - Baoguo Zhao
- The Education Ministry Key Lab of Resource Chemistry Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Frontiers Science Center of Biomimetic Catalysis Shanghai Normal University Shanghai 200234 China
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25
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NHC-catalyzed [3 + 4] annulation between 2-dromoenal and aryl 1,2-diamine: Insights into mechanisms, chemo and stereoselectivities. MOLECULAR CATALYSIS 2022. [DOI: 10.1016/j.mcat.2022.112604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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26
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Costa AM, Castro-Alvarez A, Vilarrasa J, Fillot D. Computational Comparison of the Stability of Iminium Ions and Salts from Enals and Pyrrolidine Derivatives (Aminocatalysts). European J Org Chem 2022. [DOI: 10.1002/ejoc.202200627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Anna M. Costa
- Universitat de Barcelona Facultat de Química: Universitat de Barcelona Facultat de Quimica Organic Chemistry Section Av. Diagonal 645 08028 Barcelona SPAIN
| | - Alejandro Castro-Alvarez
- Universidad de la Frontera Facultad de Medicina Ciencias Preclínicas Av. Alemania 0458 4810296 Temuco CHILE
| | - Jaume Vilarrasa
- Universitat de Barcelona Organic Chemistry Section, Fac. Quimica Av. Diagonal 645 08028 Barcelona SPAIN
| | - Daniel Fillot
- Universidad de Barcelona Facultad de Química: Universitat de Barcelona Facultat de Quimica Organic Chemistry Section (Dep. Quim. Inorg. i Org.) Diagonal 645 08028 Barcelona SPAIN
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27
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When machine learning meets molecular synthesis. TRENDS IN CHEMISTRY 2022. [DOI: 10.1016/j.trechm.2022.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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28
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Lubaev A, Rathnayake MD, Eze F, Bayeh-Romero L. Catalytic Chemo-, Regio-, Diastereo-, and Enantioselective Bromochlorination of Unsaturated Systems Enabled by Lewis Base-Controlled Chloride Release. J Am Chem Soc 2022; 144:13294-13301. [PMID: 35820071 PMCID: PMC9945878 DOI: 10.1021/jacs.2c04588] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A new strategy is described for the Lewis base-catalyzed bromochlorination of unsaturated systems that is mechanistically distinct from prior methodologies. The novelty of this method hinges on the utilization of thionyl chloride as a latent chloride source in combination with as little as 1 mol % of triphenylphosphine or triphenylphosphine oxide as Lewis basic activators. This metal-free, catalytic chemo-, regio-, and diastereoselective bromochlorination of alkenes and alkynes exhibits excellent site selectivity in polyunsaturated systems and provides access to a wide variety of vicinal bromochlorides with up to >20:1 regio- and diastereoselectivity. The precision installation of Br, Cl, and I in various combinations is also demonstrated by simply varying the commercial halogenating reagents employed. Notably, when a chiral Lewis base promoter is employed, an enantioselective bromochlorination of chalcones is possible with up to a 92:8 enantiomeric ratio when utilizing only 1-3 mol % of (DHQD)2PHAL.
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29
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Farrar EHE, Grayson MN. Machine learning and semi-empirical calculations: a synergistic approach to rapid, accurate, and mechanism-based reaction barrier prediction. Chem Sci 2022; 13:7594-7603. [PMID: 35872815 PMCID: PMC9242013 DOI: 10.1039/d2sc02925a] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 06/08/2022] [Indexed: 11/21/2022] Open
Abstract
Modern QM modelling methods, such as DFT, have provided detailed mechanistic insights into countless reactions. However, their computational cost inhibits their ability to rapidly screen large numbers of substrates and catalysts in reaction discovery. For a C-C bond forming nitro-Michael addition, we introduce a synergistic semi-empirical quantum mechanical (SQM) and machine learning (ML) approach that allows the prediction of DFT-quality reaction barriers in minutes, even on a standard laptop using widely available modelling software. Mean absolute errors (MAEs) are obtained that are below the accepted chemical accuracy threshold of 1 kcal mol-1 and substantially better than SQM methods without ML correction (5.71 kcal mol-1). Predictive power is shown to hold when the ML models are applied to an unseen set of compounds from the toxicology literature. Mechanistic insight is also achieved via the generation of full SQM transition state (TS) structures which are found to be very good approximations for the DFT-level geometries, revealing important steric interactions in some TSs. This combination of speed, accuracy, and mechanistic insight is unprecedented; current ML barrier models compromise on at least one of these important criteria.
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Affiliation(s)
- Elliot H E Farrar
- Department of Chemistry, University of Bath Claverton Down Bath BA2 7AY UK
| | - Matthew N Grayson
- Department of Chemistry, University of Bath Claverton Down Bath BA2 7AY UK
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30
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Buttard F, Champagne PA. Binding Modes and Origins of Enantioselectivity in the Phase-Transfer-Catalyzed Conjugate Cyanation of β-Trifluoromethylated Chalcones. ACS Catal 2022. [DOI: 10.1021/acscatal.2c01904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Floris Buttard
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States
| | - Pier Alexandre Champagne
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States
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31
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Kaur C, Sharma S, Thakur A, Sharma R. ASYMMETRIC SYNTHESIS: A GLANCE AT VARIOUS METHODOLOGIES FOR DIFFERENT FRAMEWORKS. CURR ORG CHEM 2022. [DOI: 10.2174/1385272826666220610162605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Abstract:
Asymmetric reactions have made a significant advancement over the past few decades and involved the production of enantiomerically pure molecules using enantioselective organocatalysis, chiral auxiliaries/substrates, and reagents via controlling the absolute stereochemistry. The laboratory synthesis from an enantiomerically impure starting material gives a combination of enantiomers which are difficult to separate for chemists in the fields of medicine, chromatography, pharmacology, asymmetric synthesis, studies of structure-function relationships of proteins, life sciences and mechanistic studies. This challenging step of separation can be avoided by the use of asymmetric synthesis. Using pharmacologically relevant scaffolds/pharmacophores, the drug designing can also be achieved using asymmetric synthesis to synthesize receptor specific pharmacologically active chiral molecules. This approach can be used to synthesize asymmetric molecules from wide variety of reactants using specific asymmetric conditions which is also beneficial for environment due to less usage and discharge of chemicals into the environment. So, in this review, we have focused on the inclusive collation of diverse mechanisms in this area, to encourage auxiliary studies of asymmetric reactions to develop selective, efficient, environment-friendly and high yielding advanced processes in asymmetric reactions.
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Affiliation(s)
- Charanjit Kaur
- Department of Pharmaceutical Chemistry, Khalsa College of Pharmacy, Amritsar, Punjab, 143002
| | - Sachin Sharma
- School of Pharmacy, Taipei Medical University, Taiwan
| | | | - Ram Sharma
- School of Pharmacy, Taipei Medical University, Taiwan
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32
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Moriyama K, Oka Y. Enantioselective Cascade Michael/Hemiaminal Formation of α,β-Unsaturated Iminoindoles with Aldehydes Using a Chiral Aminomethylpyrrolidine Catalyst Bearing a SO 2C 6F 5 Group as a Strongly Electron Withdrawing Arylsulfonyl Group. ACS Catal 2022. [DOI: 10.1021/acscatal.2c01182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Katsuhiko Moriyama
- Department of Chemistry, Graduate School of Science and Soft Molecular Activation Research Center, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
| | - Yukari Oka
- Department of Chemistry, Graduate School of Science and Soft Molecular Activation Research Center, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
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33
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Costa AM, Cascales V, Castro-Alvarez A, Vilarrasa J. Computational Study of the Stability of Pyrrolidine-Derived Iminium Ions: Exchange Equilibria between Iminium Ions and Carbonyl Compounds. ACS OMEGA 2022; 7:18247-18258. [PMID: 35694469 PMCID: PMC9178767 DOI: 10.1021/acsomega.1c07020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 05/11/2022] [Indexed: 06/15/2023]
Abstract
The tendency of carbonyl compounds to form iminium ions by reaction with pyrrolidine or chiral pyrrolidine derivatives (in other words, the relative stability to hydrolysis of these iminium ions) has been computationally examined, mainly using the M06-2X/6-311+G(d,p) method. We have thus obtained the equilibrium positions for R-CH=O + CH2=CH-CH=N+R2* → R-CH=N+R2* + CH2=CH-CH=O reactions and for related exchanges. In these exchanges, there is a transfer of a secondary amine between two carbonyl compounds. Their relative energies may be used to predict which iminium species can be predominantly formed when two or more carbonyl groups are present in a reaction medium. In the catalytic Michael additions of nucleophiles to iminium ions arising from conjugated enals, dienals, and trienals, if the formation of the new Nu-C bond is favorable, the chances of amino-catalyzed reactions to efficiently proceed, with high conversions, depend on the calculated energy values for these exchange equilibria, where the iminium tetrafluoroborates of the adducts (final iminium intermediates) must be more prone to hydrolysis than the initial iminium tetrafluoroborates. The density functional theory (DFT) calculations indicate that the MacMillan catalysts and related oxazolidinones are especially suitable in this regard.
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34
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Yang L, Zhu L, Zhang S, Hong X. Machine Learning Prediction of
Structure‐Performance
Relationship in Organic Synthesis. CHINESE J CHEM 2022. [DOI: 10.1002/cjoc.202200039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Li‐Cheng Yang
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University Hangzhou Zhejiang 310027 China
| | - Lu‐Jing Zhu
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University Hangzhou Zhejiang 310027 China
| | - Shuo‐Qing Zhang
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University Hangzhou Zhejiang 310027 China
| | - Xin Hong
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University Hangzhou Zhejiang 310027 China
- Beijing National Laboratory for Molecular Sciences, Zhongguancun North First Street NO. 2 Beijing 100190 China
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, School of Science, Westlake University, 18 Shilongshan Road Hangzhou Zhejiang 310024 China
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35
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NHC Catalyzed β-Carbon functionalization of carboxylic esters towards formation of δ-Lactams: A mechanistic study. MOLECULAR CATALYSIS 2022. [DOI: 10.1016/j.mcat.2022.112311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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36
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Ma J, Gao B, Song G, Zhang R, Wang Q, Ye Z, Chen WW, Zhao B. Asymmetric α-Allylation of Glycinate with Switched Chemoselectivity Enabled by Customized Bifunctional Pyridoxal Catalysts. Angew Chem Int Ed Engl 2022; 61:e202200850. [PMID: 35182094 DOI: 10.1002/anie.202200850] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Indexed: 12/15/2022]
Abstract
Owing to the strong nucleophilicity of the NH2 group, free-NH2 glycinates react with MBH acetates to usually deliver N-allylated products even in the absence of catalysts. Without protection of the NH2 group, chiral pyridoxal catalysts bearing an amide side chain at the C3 position of the naphthyl ring switched the chemoselectivity of the glycinates from intrinsic N-allylation to α-C allylation. The reaction formed chiral multisubstituted glutamic acid esters as SN 2'-SN 2' products in good yields with excellent stereoselectivity (up to 86 % yield, >20 : 1 dr, 97 % ee). As compared to pyridoxal catalysts bearing an amide side arm at the C2 position, the pyridoxals in this study have a bigger catalytic cavity to enable effective activation of larger electrophiles, such as MBH acetates and related intermediates. The reaction is proposed to proceed via a cooperative bifunctional catalysis pathway, which accounts for the high level of diastereo- and enantiocontrol of the pyridoxal catalysts.
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Affiliation(s)
- Jiguo Ma
- The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, and Shanghai Frontiers Science Center of Biomimetic Catalysis, Shanghai Normal University, Shanghai, 200234, China
| | - Bin Gao
- The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, and Shanghai Frontiers Science Center of Biomimetic Catalysis, Shanghai Normal University, Shanghai, 200234, China
| | - Guanshui Song
- The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, and Shanghai Frontiers Science Center of Biomimetic Catalysis, Shanghai Normal University, Shanghai, 200234, China
| | - Ruixin Zhang
- The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, and Shanghai Frontiers Science Center of Biomimetic Catalysis, Shanghai Normal University, Shanghai, 200234, China
| | - Qingfang Wang
- The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, and Shanghai Frontiers Science Center of Biomimetic Catalysis, Shanghai Normal University, Shanghai, 200234, China
| | - Zi Ye
- The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, and Shanghai Frontiers Science Center of Biomimetic Catalysis, Shanghai Normal University, Shanghai, 200234, China
| | - Wen-Wen Chen
- The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, and Shanghai Frontiers Science Center of Biomimetic Catalysis, Shanghai Normal University, Shanghai, 200234, China
| | - Baoguo Zhao
- The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, and Shanghai Frontiers Science Center of Biomimetic Catalysis, Shanghai Normal University, Shanghai, 200234, China
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37
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Ma J, Gao B, Song G, Zhang R, Wang Q, Ye Z, Chen WW, Zhao B. Asymmetric a‐Allylation of Glycinate with Switched Chemoselectivity Enabled by Customized Bifunctional Pyridoxal Catalysts. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202200850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Jiguo Ma
- Shanghai Normal University Chemistry CHINA
| | - Bin Gao
- Shanghai Normal University Chemistry CHINA
| | | | | | | | - Zi Ye
- Shanghai Normal University Chemistry CHINA
| | - Wen-Wen Chen
- Shanghai Normal University Chemistry 100 Guilin Rd 200234 Shanghai CHINA
| | - Baoguo Zhao
- Shanghai Normal University Chemistry Department 100 Guiling Rd 200234 Shanghai CHINA
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38
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Ma J, Wu Y, Yan X, Chen C, Wu T, Fan H, Liu Z, Han B. Efficient synthesis of cyclic carbonates from CO 2 under ambient conditions over Zn(betaine) 2Br 2: experimental and theoretical studies. Phys Chem Chem Phys 2022; 24:4298-4304. [PMID: 35107469 DOI: 10.1039/d1cp05553d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
It is very interesting to synthesize high value-added chemicals from CO2 under mild conditions with low energy consumption. Here, we report that a novel catalyst, Zn(betaine)2Br2, can efficiently promote the cycloaddition of CO2 with epoxides to synthesize cyclic carbonates under ambient conditions (30 °C, 1 atm). DFT calculations provide important insights into the mechanism, particularly the unusual synergistic catalytic action of Zn2+, Br- and NR4+, which is the critical factor for the outstanding performance of Zn(betaine)2Br2. The unique features of the catalyst are that it is cheap, green and very easy to prepare.
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Affiliation(s)
- Jun Ma
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid and Interface and Thermodynamics, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Yahui Wu
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid and Interface and Thermodynamics, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. .,School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xupeng Yan
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid and Interface and Thermodynamics, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. .,School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chunjun Chen
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid and Interface and Thermodynamics, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Tianbin Wu
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid and Interface and Thermodynamics, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Honglei Fan
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid and Interface and Thermodynamics, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Zhimin Liu
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid and Interface and Thermodynamics, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Buxing Han
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid and Interface and Thermodynamics, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. .,School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.,Physical Science Laboratory, Huairou National Comprehensive Science Center, No. 5 Yanqi East Second Street, Beijing 101400, China.,Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
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39
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Schulze JS, Brand RD, Hering JG, Riegger LM, Schreiner PR, Smarsly BM. DMAP immobilized on porous silica particles and monoliths for the esterification of phenylethanol in continuous flow. ChemCatChem 2022. [DOI: 10.1002/cctc.202101845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Julia S. Schulze
- Justus Liebig Universitat Giessen Institute of Physical Chemistry 35392 Giessen GERMANY
| | - Raoul D. Brand
- Justus Liebig Universitat Giessen Institute of Physical Chemistry 35392 Giessen GERMANY
| | | | - Luise M. Riegger
- Justus Liebig Universitat Giessen Institute of Physical Chemistry 35392 Giessen GERMANY
| | - Peter R. Schreiner
- Justus Liebig Universitat Giessen Institute of Organic Chemistry 35392 Giessen GERMANY
| | - Bernd M. Smarsly
- Physikalisch-Chemisches Institut Justus-Liebig-Universität Gießen Heinrich Buff Ring 17 35392 Gießen GERMANY
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40
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Cui Q, Peng J, Xu C, Lan Z. Automatic Approach to Explore the Multireaction Mechanism for Medium-Sized Bimolecular Reactions via Collision Dynamics Simulations and Transition State Searches. J Chem Theory Comput 2022; 18:910-924. [DOI: 10.1021/acs.jctc.1c00795] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Qinghai Cui
- Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety and MOE Key Laboratory of Environmental Theoretical Chemistry, SCNU Environmental Research Institute, School of Environment, South China Normal University, Guangzhou 510006, P. R. China
| | - Jiawei Peng
- Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety and MOE Key Laboratory of Environmental Theoretical Chemistry, SCNU Environmental Research Institute, School of Environment, South China Normal University, Guangzhou 510006, P. R. China
| | - Chao Xu
- Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety and MOE Key Laboratory of Environmental Theoretical Chemistry, SCNU Environmental Research Institute, School of Environment, South China Normal University, Guangzhou 510006, P. R. China
- Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education; School of Chemistry, South China Normal University, Guangzhou 510006, P. R. China
| | - Zhenggang Lan
- Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety and MOE Key Laboratory of Environmental Theoretical Chemistry, SCNU Environmental Research Institute, School of Environment, South China Normal University, Guangzhou 510006, P. R. China
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41
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Mukai M, Nagao K, Yamaguchi S, Ohmiya H. Molecular Field Analysis Using Computational-Screening Data in Asymmetric N-Heterocyclic Carbene-Copper Catalysis toward Data-driven in silico Catalyst Optimization. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2022. [DOI: 10.1246/bcsj.20210349] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Masakiyo Mukai
- Division of Pharmaceutical Sciences, Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Kazunori Nagao
- Division of Pharmaceutical Sciences, Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Shigeru Yamaguchi
- RIKEN Center for Sustainable Resource Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Hirohisa Ohmiya
- Division of Pharmaceutical Sciences, Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
- JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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42
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Lu N, Liang H, Miao C, Lan X, Qian P. Theoretical investigation of the mechanism of DMAP-promoted [4 + 2]-annulation of prop-2-ynylsulfonium with isatoic anhydride. CAN J CHEM 2022. [DOI: 10.1139/cjc-2021-0174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The mechanism for DMAP-promoted [4 + 2]-annulation of prop-2-ynylsulfonium with isatoic anhydride is investigated using the M06-2X functional. The reaction comprises isomerization of prop-2-ynylsulfonium in stage 1. Stage 2 includes DMAP-promoted deprotonation, nucleophilic addition, ring opening, and decarboxylation. Three steps of intramolecular cycloaddition, DMAP-promoted protonation, and dealkylation occur in stage 3, generating methylated DMAP and neutral thioether, which undergo double-bond isomerization to yield 3-methylthio-4-quinolone. The ability of DMAP to promote the reaction lies in the barrier decrease for alkyne isomerization, deprotonation/protonation of allenes, and dealkylation as effective bases for transferring protons and methyl groups. The roles of prop-2-ynylsulfonium and isatoic anhydride were demonstrated to be C2 and C4 synthons via Multiwfn analysis on the frontier molecular orbital. An alternative path was also confirmed by the Mayer bond order of the vital transition states.
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Affiliation(s)
- Nan Lu
- College of Chemistry and Material Science, Shandong Agricultural University, Taian City, Shandong Prov. 271018, P.R. China
- College of Chemistry and Material Science, Shandong Agricultural University, Taian City, Shandong Prov. 271018, P.R. China
| | - Hui Liang
- College of Chemistry and Material Science, Shandong Agricultural University, Taian City, Shandong Prov. 271018, P.R. China
- College of Chemistry and Material Science, Shandong Agricultural University, Taian City, Shandong Prov. 271018, P.R. China
| | - Chengxia Miao
- College of Chemistry and Material Science, Shandong Agricultural University, Taian City, Shandong Prov. 271018, P.R. China
- College of Chemistry and Material Science, Shandong Agricultural University, Taian City, Shandong Prov. 271018, P.R. China
| | - Xiaozheng Lan
- College of Chemistry and Material Science, Shandong Agricultural University, Taian City, Shandong Prov. 271018, P.R. China
- College of Chemistry and Material Science, Shandong Agricultural University, Taian City, Shandong Prov. 271018, P.R. China
| | - Ping Qian
- College of Chemistry and Material Science, Shandong Agricultural University, Taian City, Shandong Prov. 271018, P.R. China
- College of Chemistry and Material Science, Shandong Agricultural University, Taian City, Shandong Prov. 271018, P.R. China
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43
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Guo L, Wang J, Luo J, Shi Q, Wei D, Chen X. Prediction on chemoselectivity for selected organocatalytic reactions by the DFT version of the Hückel-defined free valence index. Catal Sci Technol 2022. [DOI: 10.1039/d2cy01118b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The DFT version of the Hückel-defined free valence (HFV) index has been suggested and successfully used for predicting the origin of chemoselectivity in the selected organocatalytic reactions.
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Affiliation(s)
- Limin Guo
- College of Chemistry, Institute of Green Catalysis, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan 450001, China
| | - Juanjuan Wang
- Key Laboratory of Theoretical and Computational Photochemistry of the Ministry of Education, Department of Chemistry, Beijing Normal University, Xin-wai-da-jie No. 19, Beijing 100875, China
- Key Laboratory of Beam Technology of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875, China
| | - Jing Luo
- College of Chemistry, Institute of Green Catalysis, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan 450001, China
| | - Qianqian Shi
- College of Chemistry, Institute of Green Catalysis, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan 450001, China
| | - Donghui Wei
- College of Chemistry, Institute of Green Catalysis, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan 450001, China
| | - Xuebo Chen
- College of Chemistry, Institute of Green Catalysis, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan 450001, China
- Key Laboratory of Theoretical and Computational Photochemistry of the Ministry of Education, Department of Chemistry, Beijing Normal University, Xin-wai-da-jie No. 19, Beijing 100875, China
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44
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Gallarati S, Laplaza R, Corminboeuf C. Harvesting the fragment-based nature of bifunctional organocatalysts to enhance their activity. Org Chem Front 2022. [DOI: 10.1039/d2qo00550f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Enhancing the activity of bifunctional organocatalysts: a fragment-based approach coupled with activity maps helps identifying better-performing catalytic motifs.
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Affiliation(s)
- Simone Gallarati
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Ruben Laplaza
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
- National Center for Competence in Research – Catalysis (NCCR-Catalysis), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Clemence Corminboeuf
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
- National Center for Competence in Research – Catalysis (NCCR-Catalysis), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
- National Center for Computational Design and Discovery of Novel Materials (MARVEL), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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45
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Golub T, Kano T, Maruoka K, Merten C. VCD spectroscopy distinguishes the enamine and iminium ion of a 1,1’-binaphthyl azepine. Chem Commun (Camb) 2022; 58:8412-8415. [DOI: 10.1039/d2cc02863h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a VCD spectroscopic characterization of a chiral 1,1’-binaphthyl azepine catalyst and show that the VCD spectra of an in-situ generated enamine and an ex-situ prepared iminium ion are...
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46
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Xu J, Zhang Y, Han J, Su A, Qiao H, Zhang C, Tang J, Shen X, Sun B, Yu W, Zhai S, Wang X, Wu Y, Su W, Duan H. Providing direction for mechanistic inferences in radical cascade cyclization using Transformer model. Org Chem Front 2022. [DOI: 10.1039/d2qo00188h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Even in modern organic chemistry, predicting or proposing a reaction mechanism and speculating on reaction intermediates remains challenging. For example, it is challenging to predict the regioselectivity of radical attraction...
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47
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Sun Y, Li Y, Li X, Zeng Y. Mechanism and Impact of Mono/bis(iodoimidazolium) Halogen-Bond Donor Catalysts on Michael Addition of Indole with Trans-crotonophenone: DFT Investigations. Phys Chem Chem Phys 2022; 24:6690-6698. [DOI: 10.1039/d2cp00075j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The bidentate halogen bond donor catalysts in organic reactions have attracted greatly attention in recent years. In this work, the catalytic mechanism of mono/bis(iodoimidazolium) halogen bond donor catalysts on the...
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48
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DFT Study on the Reaction Mechanism of Cyclization of 2-Hydroxy Chalcone Catalyzed by Bronsted Acid with M06-2X Functional. BULLETIN OF CHEMICAL REACTION ENGINEERING & CATALYSIS 2021. [DOI: 10.9767/bcrec.16.4.11487.796-803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Flavanones are one of the flavonoid group that has wide variety of applications such as a precursors in drug discovery. In the laboratory, flavanone is often synthesized from chalcone compounds. The conversion of chalcone to flavanone can be catalyzed by bronsted acid. The reaction mechanism for this process is proposed through the Michael addition reaction, however, the energetic details and the rate determining step for this reaction is not certainly known. This research aimed to investigate the reaction mechanism for chalcone-flavanone conversion with the present of bronsted acid as catalyst and also studied the effect of the solvent on the reaction energy profile with computational method. In this study, the modeling of the reaction mechanism for the said reaction was carried out using the DFT computational method with M06-2X functional. The computation was done both in the gas phase and in present of the solvent effect using the PCM models. The results showed that the mechanism of chalcone-flavanone conversion occurred in three steps which are protonation, cyclization, and then tautomerization. Based on these calculations, the rate determining step was the tautomerization reaction, which exhibited the same results with or without the solvent effects. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
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Yadav J, Dolas AJ, Iype E, Rangan K, Ohshita J, Kumar D, Kumar I. Asymmetric Synthesis of Bridged N-Heterocycles with Tertiary Carbon Center through Barbas Dienamine-Catalysis: Scope and Applications. J Org Chem 2021; 86:17213-17225. [PMID: 34743517 DOI: 10.1021/acs.joc.1c02295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A direct aza-Diels-Alder reaction between 2-aryl-3H-indolin-3-ones and cyclic-enones has been developed to access chiral indolin-3-one fused polycyclic bridged compounds. This method proceeds via proline-catalyzed Barbas-dienamine intermediate formation from various cyclic-enones such as 2-cyclopenten-1-one, 2-cyclohexene-1-one, and 2-cycloheptene-1-one, followed by a reaction with 2-aryl-3H-indol-3-ones. Several indolin-3-ones fusing [2.2.2], [2.2.1], and [3.2.1] skeletons decorated with a tertiary carbon chiral center have been prepared. Computational studies (DFT) supported the observed stereoselectivity in the method. The synthesized compounds have shown exciting photophysical activities and selective sensing of Pd2+ and Fe3+ ions through the fluorescence quenching "switch-off" mode.
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Affiliation(s)
- Jyothi Yadav
- Department of Chemistry, Birla Institute of Technology and Science, Pilani 333031, Rajasthan, India
| | - Atul Jankiram Dolas
- Department of Chemistry, Birla Institute of Technology and Science, Pilani 333031, Rajasthan, India
| | - Eldhose Iype
- Department of Chemical Engineering, Birla Institute of Technology and Science, Dubai Campus, Dubai 345055, United Arab Emirates
| | - Krishnan Rangan
- Department of Chemistry, Birla Institute of Technology and Science, Hyderabad Campus, Hyderabad 500078, Telangana, India
| | - Joji Ohshita
- Applied Chemistry Program, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima City, Hiroshima, 739-8527, Japan
| | - Dalip Kumar
- Department of Chemistry, Birla Institute of Technology and Science, Pilani 333031, Rajasthan, India
| | - Indresh Kumar
- Department of Chemistry, Birla Institute of Technology and Science, Pilani 333031, Rajasthan, India
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Golub TP, Merten C. Vibrational CD study on the solution phase structures of the MacMillan catalyst and its corresponding iminium ion. Phys Chem Chem Phys 2021; 23:25162-25169. [PMID: 34730148 DOI: 10.1039/d1cp04497d] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We demonstrate that VCD spectroscopy can reveal insights into the conformational preferences of the iminium ion obtained from MacMillan's imidazolidinone catalyst. For both the isolated and in situ generated iminium ion, the comparison of experimental and computed VCD spectra directly confirms that conformer 2b ("Houk-conformer") is the dominant structure in solution. This conclusion is reached without any in-depth interpretation of the spectroscopic data, just by visual comparison of the spectral signatures. For the parent catalyst 1 and its salts 1·HCl and 1·HClO4, we report a comprehensive analysis of the conformational preferences in two solvents. VCD spectroscopy is subsequently shown to be able to reveal small conformational changes induced by solute-solvent and solute-anion interactions.
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Affiliation(s)
- Tino P Golub
- Ruhr-Universität Bochum, Fakultät für Chemie und Biochemie, Organische Chemie II, Universitätsstraße 150, 44801 Bochum, Germany.
| | - Christian Merten
- Ruhr-Universität Bochum, Fakultät für Chemie und Biochemie, Organische Chemie II, Universitätsstraße 150, 44801 Bochum, Germany.
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