1
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Kemper M, Drost DA, Engelage E, Merten C. Stereochemistry Controls Dihydrogen Bonding Strengths in Chiral Amine Boranes Adducts. Angew Chem Int Ed Engl 2022; 61:e202213859. [PMID: 36245340 PMCID: PMC10099978 DOI: 10.1002/anie.202213859] [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: 09/20/2022] [Indexed: 11/07/2022]
Abstract
The growing interest in exploiting novel concepts of non-covalent interactions in catalysts and supramolecular chemistry made us revisit a special kind of hydrogen bonding: the dihydrogen bond (DHB), formed between a classical hydrogen bond donor and a hydridic hydrogen as acceptor. Herein, we investigate how the strength of the N-Hδ+ ⋅⋅⋅δ- H-B interaction and hence the DHB-driven self-aggregation of amine-borane adducts is governed by steric effects by comparing the structures and binding enthalpies of various chiral derivatives. For a diastereomeric pair of amine-boranes prepared from a chiral secondary amine, we show that the stereochemistry at the nitrogen has significant influence on the interaction enthalpy. Based on this finding, N-chiral amine boranes can be envisioned to become interesting building blocks in supramolecular chemistry to fine-tune the formation dynamics of assemblies.
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Affiliation(s)
- Michael Kemper
- Ruhr Universität Bochum, Fakultät für Chemie und Biochemie, Organische Chemie II, Universitätsstraße 150, 44801, Bochum, Germany
| | - Deborah A Drost
- Ruhr Universität Bochum, Fakultät für Chemie und Biochemie, Organische Chemie II, Universitätsstraße 150, 44801, Bochum, Germany
| | - Elric Engelage
- 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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2
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Golub TP, Feßner M, Engelage E, Merten C. Dynamic Stereochemistry of a Biphenyl‐Bisprolineamide Model Catalyst and its Imidazolidinone Intermediates. Chemistry 2022; 28:e202201317. [PMID: 35611719 PMCID: PMC9545261 DOI: 10.1002/chem.202201317] [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: 04/28/2022] [Indexed: 12/15/2022]
Abstract
In this study, we characterize the dynamic stereochemistry of a biphenyl‐2,2’‐bis(proline amide) catalyst in chloroform and DMSO as representative weakly and strongly hydrogen bonding solvents. Using vibrational circular dichroism (VCD) spectroscopy and density functional theory (DFT) based spectra calculations, we show that the preferred axial stereochemistry of the catalyst is determined by solute‐solvent interactions. Explicitly considering solvation with DMSO molecules is found to be essential to correctly predict the conformational preferences of the catalyst. Furthermore, we investigate the stereochemistry of the corresponding enamines and imidazolidinones that are formed upon reaction with isovaleraldehyde. The enamines are found to rapidly convert to endo‐imidazolidinones and the thermodynamically favored exo‐imidazolidinones are formed only slowly. The present study demonstrates that the stereochemistry of these imidazolidinones can be deduced directly from the VCD spectra analysis without any further detailed analysis of NMR spectra. Hence, we herein exemplify the use of VCD spectroscopy for an in situ characterization of intermediates relevant in asymmetric catalysts.
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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
| | - Malte Feßner
- Ruhr Universität Bochum Fakultät für Chemie und Biochemie Organische Chemie II Universitätsstraße 150 44801 Bochum Germany
| | - Elric Engelage
- 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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3
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Golub TP, Abazid AH, Nachtsheim BJ, Merten C. Structure Elucidation of
In Situ
Generated Chiral Hypervalent Iodine Complexes via Vibrational Circular Dichroism (VCD). Angew Chem Int Ed Engl 2022; 61:e202204624. [PMID: 35570718 PMCID: PMC10084129 DOI: 10.1002/anie.202204624] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Indexed: 12/23/2022]
Abstract
The structure of in situ generated chiral aryl-λ3 -iodanes obtained under oxidative reaction conditions was not yet observable with experimental techniques and their proposed structures are purely based on DFT calculations. Herein, we establish vibrational circular dichroism (VCD) spectroscopy as an experimental technique to verify DFT-calculated chiral iodane structures. Based on a chiral triazole-substituted iodoarene catalyst, we were able to elucidate a yet undescribed cationic chiral iodane as the most populated intermediate under oxidative conditions with a significant intramolecular N-I-interaction and no significant interactions with tosylate or m-chlorobenzoic acid as potential anionic ligands. Instead, aggregation of these substrates was found, which resulted in the formation of a non-coordinating anionic hydrogen bonded complex. The importance of VCD as a crucial experimental observable is further highlighted by the fact that our initial structural proposal, that was purely based on DFT calculations, could be falsified.
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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
| | - Ayham H. Abazid
- Universität Bremen Fachbereich 2—Biologie und Chemie, Institut für Organische und Analytische Chemie Germany
| | - Boris J. Nachtsheim
- Universität Bremen Fachbereich 2—Biologie und Chemie, Institut für Organische und Analytische Chemie Germany
| | - Christian Merten
- Ruhr Universität Bochum Fakultät für Chemie und Biochemie, Organische Chemie II Universitätsstraße 150 44801 Bochum Germany
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4
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Golub TP, Abazid AH, Nachtsheim BJ, Merten C. Strukturaufklärung eines chiralen
in situ
erzeugten hypervalentem Iod‐Komplex mittels VCD‐Spektroskopie. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202204624] [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)
- Tino P. Golub
- Ruhr Universität Bochum Fakultät für Chemie und Biochemie, Organische Chemie II Universitätsstraße 150 44801 Bochum Deutschland
| | - Ayham H. Abazid
- Universität Bremen Fachbereich 2 – Biologie und Chemie, Institut für Organische und Analytische Chemie (Deutschland)
| | - Boris J. Nachtsheim
- Universität Bremen Fachbereich 2 – Biologie und Chemie, Institut für Organische und Analytische Chemie (Deutschland)
| | - Christian Merten
- Ruhr Universität Bochum Fakultät für Chemie und Biochemie, Organische Chemie II Universitätsstraße 150 44801 Bochum Deutschland
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5
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Lowe JM, Bowers BE, Seo Y, Gagné MR. Modulating Electrostatic Interactions in Ion Pair Intermediates To Alter Site Selectivity in the C−O Deoxygenation of Sugars. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202007415] [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)
- Jared M. Lowe
- Department of Chemistry University of North Carolina at Chapel Hill Chapel Hill NC 27599 USA
| | - Bekah E. Bowers
- Department of Chemistry University of North Carolina at Chapel Hill Chapel Hill NC 27599 USA
| | - Youngran Seo
- Department of Chemistry University of North Carolina at Chapel Hill Chapel Hill NC 27599 USA
| | - Michel R. Gagné
- Department of Chemistry University of North Carolina at Chapel Hill Chapel Hill NC 27599 USA
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6
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Merten C. Recent Advances in the Application of Vibrational Circular Dichroism Spectroscopy for the Characterization of Asymmetric Catalysts. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000876] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Christian Merten
- Fakultät für Chemie und Biochemie Organische Chemie II Ruhr Universität Bochum Universitätsstraße 150 44801 Bochum Germany
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7
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Lowe JM, Bowers BE, Seo Y, Gagné MR. Modulating Electrostatic Interactions in Ion Pair Intermediates To Alter Site Selectivity in the C-O Deoxygenation of Sugars. Angew Chem Int Ed Engl 2020; 59:17297-17300. [PMID: 32521102 DOI: 10.1002/anie.202007415] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Indexed: 11/09/2022]
Abstract
Controlling which products one can access from the predefined biomass-derived sugars is challenging. Changing from CH2 Cl2 to the greener alternative toluene alters which C-O bonds in a sugar are cleaved by the tris(pentafluorophenyl)borane/HSiR3 catalyst system. This increases the diversity of high-value products that can be obtained through one-step, high-yielding, catalytic transformations of the mono-, di-, and oligosaccharides. Computational methods helped identify this non-intuitive outcome in low dielectric solvents to non-isotropic electrostatic enhancements in the key ion pair intermediates, which influence the reaction coordinate in the reactivity-/selectivity-determining step. Molecular-level models for these effects have far-reaching consequences in stereoselective ion pair catalysis.
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Affiliation(s)
- Jared M Lowe
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Bekah E Bowers
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Youngran Seo
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Michel R Gagné
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
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8
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Golub TP, Merten C. Stereochemistry of the Reaction Intermediates of Prolinol Ether Catalyzed Reactions Characterized by Vibrational Circular Dichroism Spectroscopy. Chemistry 2020; 26:2349-2353. [PMID: 31854022 PMCID: PMC7065232 DOI: 10.1002/chem.201905614] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Indexed: 11/24/2022]
Abstract
Spectroscopic characterizations of key reaction intermediates are often considered the final confirmation of a reaction mechanism. This proof‐of‐principle study showcases the application of vibrational circular dichroism (VCD) spectroscopy for the characterization of in situ generated reaction intermediates using the key intermediates of enamine catalysis of Jørgensen–Hayashi‐type prolinol ether catalysts as model system. By comparison of experimental and computed spectra, the enamines are shown to preferentially adopt an anti‐conformation with E‐configured C=C bond. For the parent prolinol catalyst, the structure and stereochemistry of the oxazolidine side product is determined as well. This study thus demonstrates that VCD spectra can provide insights into structural preferences of organocatalysts that utilize a covalent activation mechanism. Thereby it outlines new fields of applications for VCD spectroscopy and finally adds the technique to the toolbox of physical organic chemistry for in‐depth mechanistic studies.
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Affiliation(s)
- Tino P. Golub
- Fakultät für Chemie und Biochemie, Organische Chemie IIRuhr Universität BochumUniversitätsstrasse 15044801BochumGermany
| | - Christian Merten
- Fakultät für Chemie und Biochemie, Organische Chemie IIRuhr Universität BochumUniversitätsstrasse 15044801BochumGermany
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9
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Strudwick BH, Koenis MAJ, Sanders HJ, Nicu VP, Woutersen S, Buma WJ. A Tunable, Fullerene-Based Molecular Amplifier for Vibrational Circular Dichroism. Chemistry 2019; 25:12560-12566. [PMID: 31273849 PMCID: PMC6790965 DOI: 10.1002/chem.201902190] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 06/29/2019] [Indexed: 01/03/2023]
Abstract
Vibrational circular dichroism (VCD) studies are reported on a chiral compound in which a fullerene C60 moiety is used as an electron acceptor and local VCD amplifier for an alanine-based peptide chain. Four redox states are investigated in this study, of which three are reduced species that possess low-lying electronic states as confirmed by UV/Vis spectroelectrochemistry. VCD measurements in combination with (TD)DFT calculations are used to investigate (i) how the low-lying electronic states of the reduced species modulate the amplification of VCD signals, (ii) how this amplification depends on the distance between oscillator and amplifier, and (iii) how the spatial extent of the amplifier influences amplification. These results pave the way for further development of tailored molecular VCD amplifiers.
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Affiliation(s)
- Benjamin H. Strudwick
- Molecular Photonics Group, Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XHAmsterdamThe Netherlands
| | - Mark A. J. Koenis
- Molecular Photonics Group, Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XHAmsterdamThe Netherlands
| | - Hans J. Sanders
- Molecular Photonics Group, Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XHAmsterdamThe Netherlands
| | - Valentin P. Nicu
- Department of Environmental Science, Physics, Physical Education and SportLucian Blaga University of Sibiuloan Ratiu Street, Nr. 7-9550012SibiuRomania
| | - Sander Woutersen
- Molecular Photonics Group, Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XHAmsterdamThe Netherlands
| | - Wybren Jan Buma
- Molecular Photonics Group, Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XHAmsterdamThe Netherlands
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10
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van Lint MJ, Hall M, Faber K, van Spanning RJM, Ruijter E, Orru RVA. Stereoselective Chemoenzymatic Cascade Synthesis of the bis
-THF Core of Acetogenins. European J Org Chem 2018. [DOI: 10.1002/ejoc.201801562] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Matthijs J. van Lint
- Amsterdam Institute for Molecules, Medicines and Systems; Vrije Universiteit Amsterdam; De Boelelaan 1108 1081 HZ Amsterdam The Netherlands
| | - Mélanie Hall
- Department of Chemistry, Organic & Bioorganic Chemistry; University of Graz; Heinrichstrasse 28 8010 Graz Austria
| | - Kurt Faber
- Department of Chemistry, Organic & Bioorganic Chemistry; University of Graz; Heinrichstrasse 28 8010 Graz Austria
| | - Rob J. M. van Spanning
- Amsterdam Institute for Molecules, Medicines and Systems; Vrije Universiteit Amsterdam; De Boelelaan 1108 1081 HZ Amsterdam The Netherlands
| | - Eelco Ruijter
- Amsterdam Institute for Molecules, Medicines and Systems; Vrije Universiteit Amsterdam; De Boelelaan 1108 1081 HZ Amsterdam The Netherlands
| | - Romano V. A. Orru
- Amsterdam Institute for Molecules, Medicines and Systems; Vrije Universiteit Amsterdam; De Boelelaan 1108 1081 HZ Amsterdam The Netherlands
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11
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Kreienborg NM, Merten C. How Do Substrates Bind to a Bifunctional Thiourea Catalyst? A Vibrational CD Study on Carboxylic Acid Binding. Chemistry 2018; 24:17948-17954. [PMID: 30230065 DOI: 10.1002/chem.201804230] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Indexed: 01/14/2023]
Abstract
Knowledge about the active conformation of an asymmetric catalyst is highly valuable in order to understand its stereoinductive power, but spectroscopic access to these structures is often limited. For the example of Takemoto's bifunctional thiourea, we demonstrate the capability of VCD spectroscopy to characterize the conformational preferences of the catalyst with and without having a reactant bound to it. In particular we show that the binding orientation of carboxylic acids can easily be derived from a computationally guided analysis of the spectra. Moreover, we identify characteristic marker bands, which are only visible in the VCD spectra of the catalyst/acid mixtures but not in the corresponding IR spectra. Lastly, we also discuss the problem that the popular DFT functional M06-2X, which we found to perform exceptionally well in the calculations of vibrational frequencies for fluorinated molecules, predicts incorrect structures of the molecular clusters. We relate this poor performance in predicting the structure of the binding topologies to an overestimation of dispersive CH-π and π-π interactions, which occur due to a neglect of the solvent molecules in the clusters. VCD spectroscopy is thus shown to be a powerful tool to identify and subsequently correct such mispredictions of solution-phase structures.
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Affiliation(s)
- Nora M Kreienborg
- Ruhr-Universität Bochum, Fakultät für Chemie, Lehrstuhl für Organische Chemie II, Universitätsstraße 150, 44801, Bochum, Germany
| | - Christian Merten
- Ruhr-Universität Bochum, Fakultät für Chemie, Lehrstuhl für Organische Chemie II, Universitätsstraße 150, 44801, Bochum, Germany
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12
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Jähnigen S, Scherrer A, Vuilleumier R, Sebastiani D. VCD‐Verstärkung durch chirale Packungseffekte in molekularen Kristallen. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201805671] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Sascha Jähnigen
- Martin-Luther-Universität Halle-Wittenberg Institut für Chemie von-Danckelmann-Platz 4 Halle 06120 Deutschland
| | - Arne Scherrer
- Martin-Luther-Universität Halle-Wittenberg Institut für Chemie von-Danckelmann-Platz 4 Halle 06120 Deutschland
| | - Rodolphe Vuilleumier
- PASTEUR, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS 75005 Paris Frankreich
| | - Daniel Sebastiani
- Martin-Luther-Universität Halle-Wittenberg Institut für Chemie von-Danckelmann-Platz 4 Halle 06120 Deutschland
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13
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Jähnigen S, Scherrer A, Vuilleumier R, Sebastiani D. Chiral Crystal Packing Induces Enhancement of Vibrational Circular Dichroism. Angew Chem Int Ed Engl 2018; 57:13344-13348. [DOI: 10.1002/anie.201805671] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 06/25/2018] [Indexed: 01/15/2023]
Affiliation(s)
- Sascha Jähnigen
- Martin-Luther-Universität Halle-WittenbergInstitut für Chemie von-Danckelmann-Platz 4 Halle 06120 Germany
| | - Arne Scherrer
- Martin-Luther-Universität Halle-WittenbergInstitut für Chemie von-Danckelmann-Platz 4 Halle 06120 Germany
| | - Rodolphe Vuilleumier
- PASTEUR, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS 75005 Paris France
| | - Daniel Sebastiani
- Martin-Luther-Universität Halle-WittenbergInstitut für Chemie von-Danckelmann-Platz 4 Halle 06120 Germany
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14
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Demarque DP, Merten C. Intra- versus Intermolecular Hydrogen Bonding: Solvent-Dependent Conformational Preferences of a Common Supramolecular Binding Motif from 1
H NMR and Vibrational Circular Dichroism Spectra. Chemistry 2017; 23:17915-17922. [DOI: 10.1002/chem.201703643] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Indexed: 12/29/2022]
Affiliation(s)
- Daniel P. Demarque
- Lehrstuhl für Organische Chemie 2; Ruhr-Universität Bochum; Universitätsstraße 150 44801 Bochum Germany
- Núcleo de Pesquisa em Produtos Naturais e Sintéticos, Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto; Universidade de São Paulo (Brazil)
| | - Christian Merten
- Lehrstuhl für Organische Chemie 2; Ruhr-Universität Bochum; Universitätsstraße 150 44801 Bochum Germany
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15
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Pollok CH, Zhang Q, Tiefenbacher K, Merten C. Chirality Induction from a Chiral Guest to the Hydrogen-Bonding Network of Its Hexameric Resorcinarene Host Capsule. Chemphyschem 2017; 18:1987-1991. [PMID: 28577348 DOI: 10.1002/cphc.201700610] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Indexed: 12/19/2022]
Abstract
The hexameric capsule of resorcin[4]arene 1 is capable of encapsulating tertiary amines, which has recently been used in the application of [(1)6 (H2 O)8 ] as (co-)catalyst in various asymmetric reactions. However, not much is known about the highly asymmetric but conformationally very dynamic structure of the capsule after uptake of chiral molecules. Therefore, in this contribution, we utilize electronic circular dichroism and vibrational circular dichroism spectroscopy to investigate how several chiral guest molecules affect the structural preferences of the capsule [(1)6 (H2 O)8 ]. In particular, we show that one small chiral amine encapsulated in [(1)6 (H2 O)8 ] is sufficient to control and dictate the stereochemical preferences of the entire capsule. Furthermore, neither strong π-π interactions nor a significant steric bulk are required for this induction. The observation of such a chiral imprint of the guest's stereochemistry onto its host molecule is expected to have implications also for other supramolecular capsules.
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Affiliation(s)
- Corina H Pollok
- Ruhr-Universität Bochum, Fakultät für Chemie und Biochemie, Organische Chemie 2, Universitätsstraße 150, 44801, Bochum, Germany
| | - Qi Zhang
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056, Basel, Switzerland
| | - Konrad Tiefenbacher
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056, Basel, Switzerland.,Department of Biosystems Science and Engineering, ETH Zürich, Mattenstrasse 26, CH-4058, Basel, Switzerland
| | - Christian Merten
- Ruhr-Universität Bochum, Fakultät für Chemie und Biochemie, Organische Chemie 2, Universitätsstraße 150, 44801, Bochum, Germany
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16
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Kreienborg NM, Pollok CH, Merten C. Towards an Observation of Active Conformations in Asymmetric Catalysis: Interaction-Induced Conformational Preferences of a Chiral Thiourea Model Compound. Chemistry 2016; 22:12455-63. [DOI: 10.1002/chem.201602097] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Nora M. Kreienborg
- Organische Chemie 2; Ruhr-Universität Bochum; Universitätsstraße 150 44801 Bochum Germany
| | - Corina H. Pollok
- Organische Chemie 2; Ruhr-Universität Bochum; Universitätsstraße 150 44801 Bochum Germany
| | - Christian Merten
- Organische Chemie 2; Ruhr-Universität Bochum; Universitätsstraße 150 44801 Bochum Germany
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