1
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Xiao JX, Li FX, Ren SJ, Qu J. Studies on the Biomimetic Synthesis of Marine Ladder Polyethers via Endo-Selective Epoxide-to-Epoxonium Ring-Opening Cascades. Angew Chem Int Ed Engl 2024; 63:e202403597. [PMID: 38752455 DOI: 10.1002/anie.202403597] [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: 02/21/2024] [Indexed: 07/16/2024]
Abstract
Marine ladder polyethers have attracted the attention of chemists and biologists because of their potent biological activities. Synthetic chemists have attempted to construct their polyether frameworks by epoxide ring-opening cascades, as Nakanishi hypothesis describes. However, Baldwin's rules of ring closure state that exo-selective intramolecular cyclization of epoxy alcohols is preferred over endo-selective cyclization. Herein, we investigated epoxide ring-opening cascades of polyepoxy alcohols in [EMIM]BF4/PFTB (1-ethyl-3-methylimidazolium tetrafluoroborate /perfluoro-tert-butyl alcohol) and found that all-endo products were formed via epoxide-to-epoxonium ring-opening cyclizations (not restricted by Baldwin's rules, which only apply to intramolecular hydroxyl-to-epoxide cyclizations). We determined that the key factor enabling polyepoxy alcohols to undergo a high proportion of all-endo-selective cyclization was inhibition of exo-selective hydroxyl-to-epoxide cyclization starting from the terminal hydroxyl group of a polyepoxy alcohol. By introducing a slow-release protecting group to the terminal hydroxyl group, we could markedly increase the cyclization yields of polyether fragments with hydrogen atoms at the ring junctions. For the first time, we constructed consecutively fused six-membered-ring and fused seven-, eight-, and nine-membered-ring polyether fragments by epoxide-to-epoxonium ring-opening cyclizations through the addition of a suitable Lewis acid. We also suggest that the biosynthesis of marine ladder polyethers may proceed via epoxide-to-epoxonium ring-opening cyclization of polyepoxide.
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Affiliation(s)
- Jia-Xi Xiao
- College of Chemistry, Nankai University, The State Key Laboratory and Institute of Elemento-Organic Chemistry, Tianjin, 300071, China
| | - Feng-Xing Li
- College of Chemistry, Nankai University, The State Key Laboratory and Institute of Elemento-Organic Chemistry, Tianjin, 300071, China
| | - Shu-Jian Ren
- College of Chemistry, Nankai University, The State Key Laboratory and Institute of Elemento-Organic Chemistry, Tianjin, 300071, China
| | - Jin Qu
- College of Chemistry, Nankai University, The State Key Laboratory and Institute of Elemento-Organic Chemistry, Tianjin, 300071, China
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2
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Wu K, Kang K, Liu D, Zhang C, Wang X, Zhang M, Li Q. Gold-catalyzed endo-selective Ring-opening of Epoxides and its Application in Construction of Poly-ethers. Chemistry 2024; 30:e202400234. [PMID: 38273816 DOI: 10.1002/chem.202400234] [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: 01/19/2024] [Accepted: 01/23/2024] [Indexed: 01/27/2024]
Abstract
Tetrahydropyran and tetrahydropyran-fused poly-ethers scaffolds are found in many classes of natural products and medicinally relevant small molecules. Here we describe a catalytic system for 6-endo selective ring-opening of epoxides by Au(I) or Au(III) catalyst that provides rapid access to various tetrahydropyran-derived motifs. It also could efficiently construct the subunits of marine ladder-like poly-ethers through emulating the Nakanishi's hypothesis on the biosynthesis of these toxins. The synthetic utility of this method is also demonstrated in the preparation of the tricyclic core of tetrahydropyran-containing macrolide natural products lituarines A-C.
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Affiliation(s)
- Kehuan Wu
- Small-Molecule Drug Research Center, Shanghai Institute of Materia Medica, Chinese Academy of Science, Shanghai, 201203, China
| | - Kaiwen Kang
- Small-Molecule Drug Research Center, Shanghai Institute of Materia Medica, Chinese Academy of Science, Shanghai, 201203, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Dan Liu
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Chiyue Zhang
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Xinyu Wang
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Miaocheng Zhang
- Small-Molecule Drug Research Center, Shanghai Institute of Materia Medica, Chinese Academy of Science, Shanghai, 201203, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qi Li
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210023, China
- Small-Molecule Drug Research Center, Shanghai Institute of Materia Medica, Chinese Academy of Science, Shanghai, 201203, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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3
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Gutiérrez López MÁ, Tan ML, Renno G, Jozeliūnaitė A, Nué-Martinez JJ, Lopez-Andarias J, Sakai N, Matile S. Anion-π catalysis on carbon allotropes. Beilstein J Org Chem 2023; 19:1881-1894. [PMID: 38116243 PMCID: PMC10729121 DOI: 10.3762/bjoc.19.140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 11/29/2023] [Indexed: 12/21/2023] Open
Abstract
Anion-π catalysis, introduced in 2013, stands for the stabilization of anionic transition states on π-acidic aromatic surfaces. Anion-π catalysis on carbon allotropes is particularly attractive because high polarizability promises access to really strong anion-π interactions. With these expectations, anion-π catalysis on fullerenes has been introduced in 2017, followed by carbon nanotubes in 2019. Consistent with expectations from theory, anion-π catalysis on carbon allotropes generally increases with polarizability. Realized examples reach from enolate addition chemistry to asymmetric Diels-Alder reactions and autocatalytic ether cyclizations. Currently, anion-π catalysis on carbon allotropes gains momentum because the combination with electric-field-assisted catalysis promises transformative impact on organic synthesis.
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Affiliation(s)
| | - Mei-Ling Tan
- Department of Organic Chemistry, University of Geneva, Geneva, Switzerland
| | - Giacomo Renno
- Department of Organic Chemistry, University of Geneva, Geneva, Switzerland
| | | | | | | | - Naomi Sakai
- Department of Organic Chemistry, University of Geneva, Geneva, Switzerland
| | - Stefan Matile
- Department of Organic Chemistry, University of Geneva, Geneva, Switzerland
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4
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Gutiérrez López MÁ, Ali R, Tan ML, Sakai N, Wirth T, Matile S. Electric field-assisted anion-π catalysis on carbon nanotubes in electrochemical microfluidic devices. SCIENCE ADVANCES 2023; 9:eadj5502. [PMID: 37824606 PMCID: PMC10569703 DOI: 10.1126/sciadv.adj5502] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 09/07/2023] [Indexed: 10/14/2023]
Abstract
The vision to control the charges migrating during reactions with external electric fields is attractive because of the promise of general catalysis, emergent properties, and programmable devices. Here, we explore this idea with anion-π catalysis, that is the stabilization of anionic transition states on aromatic surfaces. Catalyst activation by polarization of the aromatic system is most effective. This polarization is induced by electric fields. The use of electrochemical microfluidic reactors to polarize multiwalled carbon nanotubes as anion-π catalysts emerges as essential. These reactors provide access to high fields at low enough voltage to prevent electron transfer, afford meaningful effective catalyst/substrate ratios, and avoid interference from additional electrolytes. Under these conditions, the rate of pyrene-interfaced epoxide-opening ether cyclizations is linearly voltage-dependent at positive voltages and negligible at negative voltages. While electromicrofluidics have been conceived for redox chemistry, our results indicate that their use for supramolecular organocatalysis has the potential to noncovalently electrify organic synthesis in the broadest sense.
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Affiliation(s)
- M. Ángeles Gutiérrez López
- Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland
| | - Rojan Ali
- School of Chemistry, Cardiff University, Park Place, Main Building, Cardiff CF10 3AT, UK
| | - Mei-Ling Tan
- Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland
| | - Naomi Sakai
- Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland
| | - Thomas Wirth
- School of Chemistry, Cardiff University, Park Place, Main Building, Cardiff CF10 3AT, UK
| | - Stefan Matile
- Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland
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5
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Tan ML, Ángeles Gutiérrez López M, Sakai N, Matile S. Anion-(π) n -π Catalytic Micelles. Angew Chem Int Ed Engl 2023; 62:e202310393. [PMID: 37574867 DOI: 10.1002/anie.202310393] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/08/2023] [Accepted: 08/11/2023] [Indexed: 08/15/2023]
Abstract
Anion-π catalysis operates by stabilizing anionic transition states on π-acidic aromatic surfaces. In anion-(π)n -π catalysis, π stacks add polarizability to strengthen interactions. In search of synthetic methods to extend π stacks beyond the limits of foldamers, the self-assembly of micelles from amphiphilic naphthalenediimides (NDIs) is introduced. To interface substrates and catalysts, charge-transfer complexes with dialkoxynaphthalenes (DANs), a classic in supramolecular chemistry, are installed. In π-stacked micelles, the rates of bioinspired ether cyclizations exceed rates on monomers in organic solvents by far. This is particularly impressive considering that anion-π catalysis in water has been elusive so far. Increasing rates with increasing π acidity of the micelles evince operational anion-(π)n -π catalysis. At maximal π acidity, autocatalytic behavior emerges. Dependence on position and order in confined micellar space promises access to emergent properties. Anion-(π)n -π catalytic micelles in water thus expand supramolecular systems catalysis accessible with anion-π interactions with an inspiring topic of general interest and great perspectives.
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Affiliation(s)
- Mei-Ling Tan
- Department of Organic Chemistry, University of Geneva, Geneva, Switzerland
| | | | - Naomi Sakai
- Department of Organic Chemistry, University of Geneva, Geneva, Switzerland
| | - Stefan Matile
- Department of Organic Chemistry, University of Geneva, Geneva, Switzerland
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6
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Gutiérrez López MÁ, Tan ML, Frontera A, Matile S. The Origin of Anion-π Autocatalysis. JACS AU 2023; 3:1039-1051. [PMID: 37124310 PMCID: PMC10131205 DOI: 10.1021/jacsau.2c00656] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 02/09/2023] [Accepted: 02/17/2023] [Indexed: 05/03/2023]
Abstract
The autocatalysis of epoxide-opening ether cyclizations on the aromatic surface of anion-π catalysts stands out as a leading example of emergent properties expected from the integration of unorthodox interactions into catalysis. A working hypothesis was proposed early on, but the mechanism of anion-π autocatalysis has never been elucidated. Here, we show that anion-π autocatalysis is almost independent of peripheral crowding in substrate and product. Inaccessible asymmetric anion-π autocatalysis and sometimes erratic reproducibility further support that the origin of anion-π autocatalysis is more complex than originally assumed. The apparent long-distance communication without physical contact calls for the inclusion of water between substrate and product on the catalytic aromatic surface. Efficient anion-π autocatalysis around equimolar amounts but poor activity in dry solvents and with excess water indicate that this inclusion of water requires high precision. Computational models suggest that two water molecules transmit dual substrate activation by the product and serve as proton shuttles along antiparallel but decoupled hydrogen-bonded chains to delocalize and stabilize evolving charge density in the transition state by "anion-π double bonds". This new transition-state model of anion-π autocatalysis provides a plausible mechanism that explains experimental results and brings anion-π catalysis to an unprecedented level of sophistication.
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Affiliation(s)
- M. Ángeles Gutiérrez López
- Department
of Organic Chemistry, University of Geneva, CH-1211 Geneva, Switzerland
- National
Centre of Competence in Research (NCCR) Molecular Systems Engineering
(MSE), CH-4002 Basel, Switzerland
| | - Mei-Ling Tan
- Department
of Organic Chemistry, University of Geneva, CH-1211 Geneva, Switzerland
- National
Centre of Competence in Research (NCCR) Molecular Systems Engineering
(MSE), CH-4002 Basel, Switzerland
| | - Antonio Frontera
- Departament
de Química, Universitat de les Illes
Balears, SP-07122 Palma de Mallorca, Spain
| | - Stefan Matile
- Department
of Organic Chemistry, University of Geneva, CH-1211 Geneva, Switzerland
- National
Centre of Competence in Research (NCCR) Molecular Systems Engineering
(MSE), CH-4002 Basel, Switzerland
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7
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Long X, Li J, Gao F, Wu H, Deng J. Bioinspired Synthesis of Spirochensilide A from Lanosterol. J Am Chem Soc 2022; 144:16292-16297. [PMID: 36054904 DOI: 10.1021/jacs.2c07198] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A bioinspired synthesis of spirochensilide A from commercially available lanosterol is reported. The synthesis features a directed C-H oxidation, a Wagner-Meerwein-type double methyl migration, a Meinwald rearrangement, and a double-bond isomerization/spiroketal formation cascade. The proposed biosynthetic speculation was modified by this synthetic sequence, which also served as a platform for the synthesis of other lanostanes with migrating methyl groups.
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Affiliation(s)
- Xianwen Long
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Jun Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Feng Gao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Hai Wu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Jun Deng
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
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8
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Bowen JI, Wang L, Crump MP, Willis CL. Synthetic and biosynthetic methods for selective cyclisations of 4,5-epoxy alcohols to tetrahydropyrans. Org Biomol Chem 2022; 20:1150-1175. [PMID: 35029626 PMCID: PMC8827043 DOI: 10.1039/d1ob01905h] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 12/21/2021] [Indexed: 12/20/2022]
Abstract
Tetrahydropyrans (THPs) are common structural motifs found in natural products and synthetic therapeutic molecules. In Nature these 6-membered oxygen heterocycles are often assembled via intramolecular reactions involving either oxy-Michael additions or ring opening of epoxy-alcohols. Indeed, the polyether natural products have been particularly widely studied due to their fascinating structures and important biological properties; these are commonly formed via endo-selective epoxide-opening cascades. In this review we outline synthetic approaches for endo-selective intramolecular epoxide ring opening (IERO) of 4,5-epoxy-alcohols and their applications in natural product synthesis. In addition, the biosynthesis of THP-containing natural products which utilise IERO reactions are reviewed.
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Affiliation(s)
- James I Bowen
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
| | - Luoyi Wang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Matthew P Crump
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
| | - Christine L Willis
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
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9
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Tian FX, Qu J. Studies on the Origin of the Stabilizing Effects of Fluorinated Alcohols and Weakly Coordinated Fluorine-Containing Anions on Cationic Reaction Intermediates. J Org Chem 2022; 87:1814-1829. [PMID: 35020378 DOI: 10.1021/acs.joc.1c02361] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Many synthetic methods that use fluorinated alcohols as solvents have been reported, and the fluorinated alcohols have been found to be crucial to the success of these methods. In addition, there have been reports indicating that adding a weakly coordinated fluorine-containing anion, such as BF4-, PF6-, or SbF6-, to fluorinated alcohols can improve yields. The boosting effect of fluorinated alcohols is attributed mainly to hydrogen bond activation. A few studies have suggested that the very polar fluorinated alcohols can stabilize cationic reaction intermediates. However, how they do so and why weakly coordinated fluorine-containing anions improve yields have not been studied in depth. Here, we used quaternary ammonium cations, a quaternary phosphonium cation, and a triaryl-substituted carbocation as models for short-lived cationic intermediates and studied the possible interactions of these cations with fluorinated alcohols and BF4-, PF6-, or SbF6-. On the basis of the results, we propose that the C-F dipoles of fluorinated alcohols and the E-F dipoles (where E is B, P, or Sb) of weakly coordinated fluorine-containing anions stabilized these cations by intermolecular charge-dipole interactions. We deduced that in the same fashion the C-F and E-F dipoles can thermodynamically stabilize cationic reaction intermediates.
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Affiliation(s)
- Feng-Xian Tian
- The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Jin Qu
- The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
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10
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Chen H, Li TR, Sakai N, Besnard C, Guénée L, Pupier M, Viger-Gravel J, Tiefenbacher K, Matile S. Decoded fingerprints of hyperresponsive, expanding product space: polyether cascade cyclizations as tools to elucidate supramolecular catalysis. Chem Sci 2022; 13:10273-10280. [PMID: 36277630 PMCID: PMC9473502 DOI: 10.1039/d2sc03991e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 08/18/2022] [Indexed: 12/03/2022] Open
Abstract
Simple enough to be understood and complex enough to be revealing, cascade cyclizations of diepoxides are introduced as new tools to characterize supramolecular catalysis. Decoded product fingerprints are provided for a consistent set of substrate stereoisomers, and shown to report on chemo-, diastereo- and enantioselectivity, mechanism and even autocatalysis. Application of the new tool to representative supramolecular systems reveals, for instance, that pnictogen-bonding catalysis is not only best in breaking the Baldwin rules but also converts substrate diastereomers into completely different products. Within supramolecular capsules, new cyclic hemiacetals from House–Meinwald rearrangements are identified, and autocatalysis on anion–π catalysts is found to be independent of substrate stereochemistry. Decoded product fingerprints further support that the involved epoxide-opening polyether cascade cyclizations are directional, racemization-free, and interconnected, at least partially. The discovery of unique characteristics for all catalysts tested would not have been possible without decoded cascade cyclization fingerprints, thus validating the existence and significance of privileged platforms to elucidate supramolecular catalysis. Once decoded, cascade cyclization fingerprints are easily and broadly applicable, ready for use in the community. Hyperresponsive XL product space identifies polyether cascade fingerprinting as an attractive tool to elucidate supramolecular catalysis, including pnictogen-bonding, capsule and anion–π catalysts.![]()
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Affiliation(s)
- Hao Chen
- National Centre of Competence in Research (NCCR) Molecular Systems Engineering, BPR 1095, Basel, Switzerland
- School of Chemistry and Biochemistry University of Geneva, Geneva, Switzerland
| | - Tian-Ren Li
- National Centre of Competence in Research (NCCR) Molecular Systems Engineering, BPR 1095, Basel, Switzerland
- Department of Chemistry, University of Basel, Basel, Switzerland
| | - Naomi Sakai
- National Centre of Competence in Research (NCCR) Molecular Systems Engineering, BPR 1095, Basel, Switzerland
- School of Chemistry and Biochemistry University of Geneva, Geneva, Switzerland
| | - Celine Besnard
- School of Chemistry and Biochemistry University of Geneva, Geneva, Switzerland
| | - Laure Guénée
- School of Chemistry and Biochemistry University of Geneva, Geneva, Switzerland
| | - Marion Pupier
- School of Chemistry and Biochemistry University of Geneva, Geneva, Switzerland
| | | | - Konrad Tiefenbacher
- National Centre of Competence in Research (NCCR) Molecular Systems Engineering, BPR 1095, Basel, Switzerland
- Department of Chemistry, University of Basel, Basel, Switzerland
- Department of Biosystems Science and Engineering, ETH, Zurich, Basel, Switzerland
| | - Stefan Matile
- National Centre of Competence in Research (NCCR) Molecular Systems Engineering, BPR 1095, Basel, Switzerland
- School of Chemistry and Biochemistry University of Geneva, Geneva, Switzerland
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11
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Sakai T, Mizuno S, Sone A, Hori Y, Yamazaki W, Takazawa K, Mori Y. Biomimetic Construction of a syn-2,7-Dimethyloxepane Ring via 7- Endo Cyclization. J Org Chem 2021; 87:579-594. [PMID: 34958571 DOI: 10.1021/acs.joc.1c02600] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
syn-2,7-Dimethyloxepane is a unique structure observed in natural ladder-shaped polycyclic ethers (LSPs), such as Caribbean ciguatoxins, gymnocin-B, and brevisulcenal-F that exhibit potent biological activities. Thus, the successful construction of this seven-membered ring is desirable, but its ring strain and the 1,3-repulsion between its two methyl groups makes this process difficult. Herein, we prepared syn-2,7-dimethyloxepanes via 7-endo cyclizations of vinyl epoxides that break Baldwin's rules. Such a biomimetic approach to syn-2,7-dimethyloxepanes has not yet been reported; however, we achieved this challenging cyclization with the aid of a cis-olefin tether and an unsubstituted vinyl group. The NO-ring fragment of gymnocin-B was also prepared from one of these 7-endo cyclized products, demonstrating the potential application of this strategy in constructing bioactive LSPs.
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Affiliation(s)
- Takeo Sakai
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Sae Mizuno
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Akitaka Sone
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Yasuko Hori
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Wakana Yamazaki
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Keisuke Takazawa
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Yuji Mori
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
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12
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Humeniuk H, Gini A, Hao X, Coelho F, Sakai N, Matile S. Pnictogen-Bonding Catalysis and Transport Combined: Polyether Transporters Made In Situ. JACS AU 2021; 1:1588-1593. [PMID: 34723261 PMCID: PMC8549043 DOI: 10.1021/jacsau.1c00345] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Indexed: 05/16/2023]
Abstract
The combination of catalysis and transport across lipid bilayer membranes promises directional access to a solvent-free and structured nanospace that could accelerate, modulate, and, at best, enable new chemical reactions. To elaborate on these expectations, anion transport and catalysis with pnictogen and tetrel bonds are combined with polyether cascade cyclizations into bioinspired cation transporters. Characterized separately, synergistic anion and cation transporters of very high activity are identified. Combined for catalysis in membranes, cascade cyclizations are found to occur with a formal rate enhancement beyond one million compared to bulk solution and product formation is detected in situ as an increase in transport activity. With this operational system in place, intriguing perspectives open up to exploit all aspects of this unique nanospace for important chemical transformations.
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13
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Hao X, Li TR, Chen H, Gini A, Zhang X, Rosset S, Mazet C, Tiefenbacher K, Matile S. Bioinspired Ether Cyclizations within a π-Basic Capsule Compared to Autocatalysis on π-Acidic Surfaces and Pnictogen-Bonding Catalysts. Chemistry 2021; 27:12215-12223. [PMID: 34060672 PMCID: PMC8456975 DOI: 10.1002/chem.202101548] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Indexed: 12/15/2022]
Abstract
While the integration of supramolecular principles in catalysis attracts increasing attention, a direct comparative assessment of the resulting systems catalysts to work out distinct characteristics is often difficult. Herein is reported how the broad responsiveness of ether cyclizations to diverse inputs promises to fill this gap. Cyclizations in the confined, π-basic and Brønsted acidic interior of supramolecular capsules, for instance, are found to excel with speed (exceeding general Brønsted acid and hydrogen-bonding catalysts by far) and selective violations of the Baldwin rules (as extreme as the so far unique pnictogen-bonding catalysts). The complementary cyclization on π-acidic aromatic surfaces remains unique with regard to autocatalysis, which is shown to be chemo- and diastereoselective with regard to product-like co-catalysts but, so far, not enantioselective.
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Affiliation(s)
- Xiaoyu Hao
- Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1121, Geneva, Switzerland.,NCCR Molecular Systems Engineering BPR 1095, Mattenstrasse 24a, CH-4058, Basel, Switzerland.,College of Materials, Chemistry and Chemical Engineering, Chengdu University of Technology, 1 Dongsan Road Erxianqiao, Chengdu, 610059, P.R. China
| | - Tian-Ren Li
- NCCR Molecular Systems Engineering BPR 1095, Mattenstrasse 24a, CH-4058, Basel, Switzerland.,Department of Chemistry, University of Basel, Mattenstrasse 24a, CH-4058, Basel, Switzerland
| | - Hao Chen
- Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1121, Geneva, Switzerland.,NCCR Molecular Systems Engineering BPR 1095, Mattenstrasse 24a, CH-4058, Basel, Switzerland
| | - Andrea Gini
- Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1121, Geneva, Switzerland.,NCCR Molecular Systems Engineering BPR 1095, Mattenstrasse 24a, CH-4058, Basel, Switzerland
| | - Xiang Zhang
- Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1121, Geneva, Switzerland.,NCCR Molecular Systems Engineering BPR 1095, Mattenstrasse 24a, CH-4058, Basel, Switzerland.,Shaanxi Key Laboratory of Natural Products and Chemical Biology, College of Science, Northwest A&F University, Xianyang Shi, Yangling, 712100, P. R. China
| | - Stéphane Rosset
- Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1121, Geneva, Switzerland
| | - Clément Mazet
- Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1121, Geneva, Switzerland
| | - Konrad Tiefenbacher
- NCCR Molecular Systems Engineering BPR 1095, Mattenstrasse 24a, CH-4058, Basel, Switzerland.,Department of Chemistry, University of Basel, Mattenstrasse 24a, CH-4058, Basel, Switzerland.,Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, CH-4058, Basel, Switzerland
| | - Stefan Matile
- Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1121, Geneva, Switzerland.,NCCR Molecular Systems Engineering BPR 1095, Mattenstrasse 24a, CH-4058, Basel, Switzerland
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14
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Paraja M, Gini A, Sakai N, Matile S. Pnictogen‐Bonding Catalysis: An Interactive Tool to Uncover Unorthodox Mechanisms in Polyether Cascade Cyclizations. Chemistry 2020; 26:15471-15476. [DOI: 10.1002/chem.202003426] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/05/2020] [Indexed: 12/28/2022]
Affiliation(s)
- Miguel Paraja
- Department of Organic Chemistry University of Geneva Geneva Switzerland
| | - Andrea Gini
- Department of Organic Chemistry University of Geneva Geneva Switzerland
| | - Naomi Sakai
- Department of Organic Chemistry University of Geneva Geneva Switzerland
| | - Stefan Matile
- Department of Organic Chemistry University of Geneva Geneva Switzerland
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