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Pérez-Sánchez JC, Herrera RP, Gimeno MC. The Potential of Self-Activating Au(I) Complexes in Gold Catalysis. Chemistry 2024; 30:e202401825. [PMID: 38818661 DOI: 10.1002/chem.202401825] [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: 05/09/2024] [Revised: 05/28/2024] [Accepted: 05/28/2024] [Indexed: 06/01/2024]
Abstract
Gold catalysis has emerged as a groundbreaking field in synthetic chemistry, revolutionizing numerous organic transformations. Despite the significant achieved advancements, the mechanistic understanding behind many gold-catalyzed reactions remains elusive. This Concept article covers the so-called "self-activating" Au(I) complexes, sorting out their pivotal role in gold catalysis. We comment on how Au(I) complexes can undergo self-activation, triggering diverse catalytic transformations without the need for external additives. The most important examples reported so far that underlie the catalytic activity of these species are discussed. This intrinsic reactivity represents a paradigm shift in gold catalysis, offering new avenues for the design of efficient and sustainable catalytic systems. Furthermore, we explore the factors influencing the stability, reactivity, and selectivity of these Au(I) complexes, providing insights into their synthetic utility and potential applications. This area of research not only advances our fundamental understanding of gold catalysis but also paves the way for the development of novel catalytic strategies with broad implications in organic synthesis and the chemical industry.
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Affiliation(s)
- Juan Carlos Pérez-Sánchez
- Department of Inorganic Chemistry, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, C/Pedro Cerbuna 12, Zaragoza, 50009, Spain
- Department of Organic Chemistry, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, C/Pedro Cerbuna 12, Zaragoza, 50009, Spain
| | - Raquel P Herrera
- Department of Organic Chemistry, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, C/Pedro Cerbuna 12, Zaragoza, 50009, Spain
| | - M Concepción Gimeno
- Department of Inorganic Chemistry, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, C/Pedro Cerbuna 12, Zaragoza, 50009, Spain
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2
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Alemán J, Humbrías-Martín J, Del Río-Rodríguez R, Aguilar-Galindo F, Díaz-Tendero S, Fernández-Salas JA. Bicarbonate-binding catalysis for the enantioselective desymmetrization of keto sulfonium salts. Nat Commun 2024; 15:4727. [PMID: 38830865 PMCID: PMC11148132 DOI: 10.1038/s41467-024-48832-x] [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: 09/16/2023] [Accepted: 05/14/2024] [Indexed: 06/05/2024] Open
Abstract
Herein, an enantioselective desymmetrization of cyclic keto sulfonium salts through enantioselective deprotonation/ring opening process by anion-binding catalysis is presented. We report a squaramide/HCO3- complex as catalytic active species which is able to stereo-differentiate two enantiomeric protons, triggering the ring opening event taking advantage of the great tendency of sulfonium salts to act as leaving groups. Thus, this desymmetrization methodology give rise to β-methylsulfenylated sulfa-Michael addition type products with excellent yields and very good enantioselectivities. The bifunctional organocatalyst has been demonstrated to be capable of activating simultaneously the base and the keto sulfonium salt by DFT calculations and experimental proofs.
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Affiliation(s)
- José Alemán
- Departamento de Química Orgánica (módulo 1), Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain.
- Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Madrid, Spain.
- Center for Innovation in Advanced Chemistry (ORFEO-CINQA), Universidad Autónoma de Madrid, Madrid, Spain.
| | - Jorge Humbrías-Martín
- Departamento de Química Orgánica (módulo 1), Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain
| | - Roberto Del Río-Rodríguez
- Departamento de Química Orgánica (módulo 1), Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain
| | - Fernando Aguilar-Galindo
- Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Madrid, Spain
- Departamento de Química, Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain
| | - Sergio Díaz-Tendero
- Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Madrid, Spain
- Departamento de Química, Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid, Spain
| | - Jose A Fernández-Salas
- Departamento de Química Orgánica (módulo 1), Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain.
- Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Madrid, Spain.
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3
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Li Z, Wang B, Zhang C, Lo WY, Yang L, Sun J. Catalytic Enantioselective Nucleophilic α-Chlorination of Ketones with NaCl. J Am Chem Soc 2024; 146:2779-2788. [PMID: 38238317 DOI: 10.1021/jacs.3c12826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Catalytic enantioselective α-chlorination of ketones is a highly desirable process. Different from the conventional approaches that employ corrosive electrophilic chlorination reagents, the process disclosed here employs nucleophilic chloride, aqueous NaCl solution, and even seawater, as green inexpensive chlorine sources. This mechanistically distinct and electronically opposite approach provides facile access to diverse highly enantioenriched acyclic α-chloro ketones that are less straightforward by conventional approaches. With a chiral thiourea catalyst, a range of racemic α-keto sulfonium salts underwent enantioconvergent carbon-chlorine bond formation with high efficiency and excellent enantioselectivity under mild conditions. The sulfonium motif plays a crucial triple role by permitting smooth dynamic kinetic resolution to take place via a chiral anion binding mechanism in a well-designed phase-transfer system. This protocol represents a new general platform for the asymmetric nucleophilic α-functionalization of carbonyl compounds.
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Affiliation(s)
- Zhiyang Li
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration & Reconstruction, The Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong SAR 999077, China
- Shenzhen Research Institute, HKUST, No. 9 Yuexing First Rd, Shenzhen 518057, China
| | - Baocheng Wang
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration & Reconstruction, The Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong SAR 999077, China
| | - Chaoshen Zhang
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration & Reconstruction, The Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong SAR 999077, China
| | - Wai Yam Lo
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration & Reconstruction, The Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong SAR 999077, China
| | - Liangliang Yang
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration & Reconstruction, The Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong SAR 999077, China
| | - Jianwei Sun
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration & Reconstruction, The Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong SAR 999077, China
- Shenzhen Research Institute, HKUST, No. 9 Yuexing First Rd, Shenzhen 518057, China
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4
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Manna A, Joshi H, Singh VK. Organocatalytic Asymmetric Direct Vinylogous Michael Initiated Ring Closure Reaction of 4-Nitroisoxazole Derivatives to 3-Isopropylidene Oxindoles. J Org Chem 2023; 88:15937-15946. [PMID: 37885257 DOI: 10.1021/acs.joc.3c02125] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
Herein, we present the first ever use of 3-isopropylidene oxindoles as electrophiles in vinylogous Michael initiated ring closure reaction (MIRC). Among the various alkylidene oxindoles used in enantioselective spirocyclization reactions, isopropylidene oxindoles are the least explored to date. The competing reactivity of isopropylidene oxindoles (electrophilicity vs nucleophilicity) in the presence of a chiral organocatalyst is controlled by the logical selection of a more reactive nucleophile. The methodology produces a library of densely substituted highly enantioenriched spirocyclopropyl oxindoles with excellent yield and stereoselectivities. Moreover, the first enantioselective synthesis of HIV-1 NNRT inhibitor indicates the importance of our synthesized spiro-cyclopropyl oxindole core.
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Affiliation(s)
- Abhijit Manna
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208 016, India
| | - Harshit Joshi
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208 016, India
| | - Vinod K Singh
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208 016, India
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5
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Aleksiev M, García Mancheño O. Enantioselective dearomatization reactions of heteroarenes by anion-binding organocatalysis. Chem Commun (Camb) 2023; 59:3360-3372. [PMID: 36790499 PMCID: PMC10019134 DOI: 10.1039/d2cc07101k] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Catalytic asymmetric dearomatization of heteroaromatic compounds has received considerable attention in the last few years, since it allows for a fast expansion of the chemical space by converting relatively simple, flat molecules into complex, three dimensional structures with added value. Among different approaches, remarkable progress has been recently achieved by the development of organocatalytic dearomatization methods. In particular, the anion-binding catalysis technology has emerged as a potent alternative to metal catalysis, which together with the design of novel, tunable anion-receptor motifs, has provided new entries for the enantioselective dearomatization of heteroarenes through a chiral contact ion pair formation by activation of the electrophilic reaction partner. In this feature, we provide an overview of the different methodologies and advances in anion-binding catalyzed dearomatization reactions of different heteroarenes.
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Affiliation(s)
- Martin Aleksiev
- Organic Chemistry Institute, University of Münster, Corrensstraße 36/40, 48149 Münster, Germany.
| | - Olga García Mancheño
- Organic Chemistry Institute, University of Münster, Corrensstraße 36/40, 48149 Münster, Germany.
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Adili A, Webster JP, Zhao C, Mallojjala SC, Romero-Reyes MA, Ghiviriga I, Abboud KA, Vetticatt MJ, Seidel D. Mechanism of a Dually Catalyzed Enantioselective Oxa-Pictet-Spengler Reaction and the Development of a Stereodivergent Variant. ACS Catal 2023; 13:2240-2249. [PMID: 37711191 PMCID: PMC10501388 DOI: 10.1021/acscatal.2c05484] [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] [Indexed: 01/28/2023]
Abstract
Enantioselective oxa-Pictet-Spengler reactions of tryptophol with aldehydes proceed under weakly acidic conditions utilizing a combination of two catalysts, an indoline HCl salt and a bisthiourea compound. Mechanistic investigations revealed the roles of both catalysts and confirmed the involvement of oxocarbenium ion intermediates, ruling out alternative scenarios. A stereochemical model was derived from density functional theory calculations, which provided the basis for the development of a highly enantioselective stereodivergent variant with racemic tryptophol derivatives.
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Affiliation(s)
- Alafate Adili
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - John-Paul Webster
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
| | - Chenfei Zhao
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
| | | | - Moises A Romero-Reyes
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Ion Ghiviriga
- Center for NMR Spectroscopy, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Khalil A Abboud
- Center for X-ray Crystallography, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Mathew J Vetticatt
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
| | - Daniel Seidel
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
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Samha MH, Wahlman JLH, Read JA, Werth J, Jacobsen EN, Sigman MS. Exploring Structure-Function Relationships of Aryl Pyrrolidine-Based Hydrogen-Bond Donors in Asymmetric Catalysis Using Data-Driven Techniques. ACS Catal 2022; 12:14836-14845. [PMID: 36816226 PMCID: PMC9937582 DOI: 10.1021/acscatal.2c04824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Hydrogen bond-based organocatalysts rely on networks of attractive noncovalent interactions (NCIs) to impart enantioselectivity. As a specific example, aryl pyrrolidine substituted urea, thiourea, and squaramide organocatalysts function cooperatively through hydrogen bonding and difficult-to-predict NCIs as a function of the reaction partners. To uncover the synergistic effect of the structural components of this catalyst class, we applied data science tools to study various model reactions using a derivatized, aryl pyrrolidine-based, hydrogen-bond donor (HBD) catalyst library. Through a combination of experimentally collected data and data mined from previous reports, statistical models were constructed, illuminating the general features necessary for high enantioselectivity. A distinct dependence on the identity of the electrophilic reaction partner and HBD catalyst is observed, suggesting that a general interaction is conserved throughout the reactions analyzed. The resulting models also demonstrate predictive capability by the successful improvement of a previously reported reaction using out-of-sample reaction components. Overall, this study highlights the power of data science in exploring mechanistic hypotheses in asymmetric HBD catalysis and provides a prediction platform applicable in future reaction optimization.
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Affiliation(s)
- Mohammad H. Samha
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Julie L. H. Wahlman
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Jacquelyne A. Read
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States; Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Jacob Werth
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Eric N. Jacobsen
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Matthew S. Sigman
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
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8
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Shennan BDA, Berheci D, Crompton JL, Davidson TA, Field JL, Williams BA, Dixon DJ. Branching out: redox strategies towards the synthesis of acyclic α-tertiary ethers. Chem Soc Rev 2022; 51:5878-5929. [PMID: 35770619 DOI: 10.1039/d1cs00669j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Acyclic α-tertiary ethers represent a highly prevalent functionality, common to high-value bioactive molecules, such as pharmaceuticals and natural products, and feature as crucial synthetic handles in their construction. As such their synthesis has become an ever-more important goal in synthetic chemistry as the drawbacks of traditional strong base- and acid-mediated etherifications have become more limiting. In recent years, the generation of highly reactive intermediates via redox approaches has facilitated the synthesis of highly sterically-encumbered ethers and accordingly these strategies have been widely applied in α-tertiary ether synthesis. This review summarises and appraises the state-of-the-art in the application of redox strategies enabling acyclic α-tertiary ether synthesis.
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Affiliation(s)
- Benjamin D A Shennan
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Diana Berheci
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Jessica L Crompton
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Timothy A Davidson
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Joshua L Field
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Benedict A Williams
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Darren J Dixon
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK.
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Abdurakhmanova ER, Cmoch P, Szumna A. Three modes of interactions between anions and phenolic macrocycles: a comparative study. Org Biomol Chem 2022; 20:5095-5103. [PMID: 35699382 DOI: 10.1039/d2ob00880g] [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
Macrocyclic polyphenolic compounds such as resorcin[4]arenes can be considered as multidentate anion receptors. In the current work, we combine new experimental data and reports from the previous literature (solution data and deposited crystal structures from the CCDC) to systematically analyze binding motifs between resorcin[4]arene derivatives and anions, determine the role of supporting interactions from CH donors, ion pairing and estimate their relative strength. We have found that in medium polarity solvents (THF) anion binding is a main driving force for the formation of complexes between resorcinarenes and Alk4NX salts. Three binding modes have been detected using 1H NMR and DOSY, depending on the type of additional interactions. Mode I was observed for upper-rim unsubstituted resorcinarenes, which use OH groups and aromatic CH from the upper rim as hydrogen bond donors to form multidentate and multivalent binding sites at the upper rim. Mode II was observed for upper-rim halogenated resorcinarenes (tetrabromo- and tetraiodo-derivatives), which use OH groups and aliphatic CH atoms from the bridges to support the chelation of anions between aromatic units. This binding mode is also multidentate and multivalent, but weaker and more anion-selective than mode I (works effectively for chlorides but not for bromides). For O-substituted derivatives, mode III is observed, with anions bound in a nest formed by aromatic CH atoms in the lower rim (multidentate but monovalent binding). The relative strength of these three binding modes, their solvent-dependence, and emergence in the crystal structures (CCDC) have been evaluated.
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Affiliation(s)
- Esma R Abdurakhmanova
- Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
| | - Piotr Cmoch
- Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
| | - Agnieszka Szumna
- Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
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10
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Šebesta R. New advances in asymmetric organocatalysis. Beilstein J Org Chem 2022; 18:240-242. [PMID: 35330781 PMCID: PMC8919419 DOI: 10.3762/bjoc.18.28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 02/23/2022] [Indexed: 11/23/2022] Open
Affiliation(s)
- Radovan Šebesta
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 842 15 Bratislava, Slovakia
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Kutateladze DA, Jacobsen EN. Cooperative Hydrogen-Bond-Donor Catalysis with Hydrogen Chloride Enables Highly Enantioselective Prins Cyclization Reactions. J Am Chem Soc 2021; 143:20077-20083. [PMID: 34812618 PMCID: PMC8717859 DOI: 10.1021/jacs.1c10890] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cooperative asymmetric catalysis with hydrogen chloride (HCl) and chiral dual-hydrogen-bond donors (HBDs) is applied successfully to highly enantioselective Prins cyclization reactions of a wide variety of simple alkenyl aldehydes. The optimal chiral catalysts were designed to withstand the strongly acidic reaction conditions and were found to induce rate accelerations of 2 orders of magnitude over reactions catalyzed by HCl alone. We propose that the combination of strong mineral acids and chiral hydrogen-bond-donor catalysts may represent a general strategy for inducing enantioselectivity in reactions that require highly acidic conditions.
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Affiliation(s)
- Dennis A. Kutateladze
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Eric N. Jacobsen
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
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Organocatalysis: A Tool of Choice for the Enantioselective Nucleophilic Dearomatization of Electron-Deficient Six-Membered Ring Azaarenium Salts. Catalysts 2021. [DOI: 10.3390/catal11101249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Nucleophilic dearomatization of azaarenium salts is a powerful strategy to access 3D scaffolds of interest from easily accessible planar aromatic azaarene compounds. Moreover, this approach yields complex dihydroazaarenes by allowing the functionalization of the scaffold simultaneously to the dearomatization step. On the other side, organocatalysis is nowadays recognized as one of the pillars of the asymmetric catalysis field of research and is well-known to afford a high level of enantioselectivity for a myriad of transformations thanks to well-organized transition states resulting from low-energy interactions (electrostatic and/or H-bonding interactions…). Consequently, in the last fifteen years, organocatalysis has met great success in nucleophilic dearomatization of azaarenium salts. This review summarizes the work achieved up to date in the field of organocatalyzed nucleophilic dearomatization of azaarenium salts (mainly pyridinium, quinolinium, quinolinium and acridinium salts). A classification by organocatalytic mode of activation will be disclosed by shedding light on their related advantages and drawbacks. The versatility of the dearomatization approach will also be demonstrated by discussing several chemical transformations of the resulting dihydroazaarenes towards the synthesis of structurally complex compounds.
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