1
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Chen S, Katsonis N, Leigh DA, Patanapongpibul M, Ryabchun A, Zhang L. Changing Liquid Crystal Helical Pitch with a Reversible Rotaxane Switch. Angew Chem Int Ed Engl 2024; 63:e202401291. [PMID: 38445723 DOI: 10.1002/anie.202401291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 03/05/2024] [Accepted: 03/06/2024] [Indexed: 03/07/2024]
Abstract
The transmission of chiral information between the molecular, meso and microscopic scales is a facet of biology that remains challenging to understand mechanistically and to mimic with artificial systems. Here we demonstrate that the dynamic change in the expression of the chirality of a rotaxane can be transduced into a change in pitch of a soft matter system. Shuttling the position of the macrocycle from far-away-from to close-to a point-chiral center on the rotaxane axle changes the expression of the chiral information that is transmitted across length scales; from nanometer scale constitutional chirality that affects the conformation of the macrocycle, to the centimeter scale chirality of the liquid crystal phase, significantly changing the pitch length of the chiral nematic structure.
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Affiliation(s)
- Sujun Chen
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, P. R. China
| | - Nathalie Katsonis
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - David A Leigh
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, P. R. China
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Manee Patanapongpibul
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - Alexander Ryabchun
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - Liang Zhang
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, P. R. China
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2
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Zhang M, Nixon R, Schaufelberger F, Pirvu L, De Bo G, Leigh DA. Mechanical scission of a knotted polymer. Nat Chem 2024:10.1038/s41557-024-01510-3. [PMID: 38649468 DOI: 10.1038/s41557-024-01510-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 03/18/2024] [Indexed: 04/25/2024]
Abstract
Molecular knots and entanglements form randomly and spontaneously in both biological and synthetic polymer chains. It is known that macroscopic materials, such as ropes, are substantially weakened by the presence of knots, but until now it has been unclear whether similar behaviour occurs on a molecular level. Here we show that the presence of a well-defined overhand knot in a polymer chain substantially increases the rate of scission of the polymer under tension (≥2.6× faster) in solution, because deformation of the polymer backbone induced by the tightening knot activates otherwise unreactive covalent bonds. The fragments formed upon severing of the knotted chain differ from those that arise from cleavage of a similar, but unknotted, polymer. Our solution studies provide experimental evidence that knotting can contribute to higher mechanical scission rates of polymers. It also demonstrates that entanglement design can be used to generate mechanophores that are among the most reactive described to date, providing opportunities to increase the reactivity of otherwise inert functional groups.
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Affiliation(s)
- Min Zhang
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Robert Nixon
- Department of Chemistry, University of Manchester, Manchester, UK
| | | | - Lucian Pirvu
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Manchester, UK.
| | - David A Leigh
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China.
- Department of Chemistry, University of Manchester, Manchester, UK.
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3
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Borsley S, Leigh DA, Roberts BMW. Molecular Ratchets and Kinetic Asymmetry: Giving Chemistry Direction. Angew Chem Int Ed Engl 2024:e202400495. [PMID: 38568047 DOI: 10.1002/anie.202400495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Indexed: 05/03/2024]
Abstract
Over the last two decades ratchet mechanisms have transformed the understanding and design of stochastic molecular systems-biological, chemical and physical-in a move away from the mechanical macroscopic analogies that dominated thinking regarding molecular dynamics in the 1990s and early 2000s (e.g. pistons, springs, etc), to the more scale-relevant concepts that underpin out-of-equilibrium research in the molecular sciences today. Ratcheting has established molecular nanotechnology as a research frontier for energy transduction and metabolism, and has enabled the reverse engineering of biomolecular machinery, delivering insights into how molecules 'walk' and track-based synthesisers operate, how the acceleration of chemical reactions enables energy to be transduced by catalysts (both motor proteins and synthetic catalysts), and how dynamic systems can be driven away from equilibrium through catalysis. The recognition of molecular ratchet mechanisms in biology, and their invention in synthetic systems, is proving significant in areas as diverse as supramolecular chemistry, systems chemistry, dynamic covalent chemistry, DNA nanotechnology, polymer and materials science, molecular biology, heterogeneous catalysis, endergonic synthesis, the origin of life, and many other branches of chemical science. Put simply, ratchet mechanisms give chemistry direction. Kinetic asymmetry, the key feature of ratcheting, is the dynamic counterpart of structural asymmetry (i.e. chirality). Given the ubiquity of ratchet mechanisms in endergonic chemical processes in biology, and their significance for behaviour and function from systems to synthesis, it is surely just as fundamentally important. This Review charts the recognition, invention and development of molecular ratchets, focussing particularly on the role for which they were originally envisaged in chemistry, as design elements for molecular machinery. Different kinetically asymmetric systems are compared, and the consequences of their dynamic behaviour discussed. These archetypal examples demonstrate how chemical systems can be driven inexorably away from equilibrium, rather than relax towards it.
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Affiliation(s)
- Stefan Borsley
- Department of Chemistry, The University of Manchester, Oxford Road, M13 9PL, Manchester, United Kingdom
| | - David A Leigh
- Department of Chemistry, The University of Manchester, Oxford Road, M13 9PL, Manchester, United Kingdom
| | - Benjamin M W Roberts
- Department of Chemistry, The University of Manchester, Oxford Road, M13 9PL, Manchester, United Kingdom
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4
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Qiu C, Li Z, Leigh DA, Duan B, Stucky JE, Kim N, Xie G, Lu KP, Zhou XZ. The role of the Pin1- cis P-tau axis in the development and treatment of vascular contribution to cognitive impairment and dementia and preeclampsia. Front Cell Dev Biol 2024; 12:1343962. [PMID: 38628595 PMCID: PMC11019028 DOI: 10.3389/fcell.2024.1343962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Accepted: 03/14/2024] [Indexed: 04/19/2024] Open
Abstract
Tauopathies are neurodegenerative diseases characterized by deposits of abnormal Tau protein in the brain. Conventional tauopathies are often defined by a limited number of Tau epitopes, notably neurofibrillary tangles, but emerging evidence suggests structural heterogeneity among tauopathies. The prolyl isomerase Pin1 isomerizes cis P-tau to inhibit the development of oligomers, tangles and neurodegeneration in multiple neurodegenerative diseases such as Alzheimer's disease, traumatic brain injury, vascular contribution to cognitive impairment and dementia (VCID) and preeclampsia (PE). Thus, cis P-tau has emerged as an early etiological driver, blood marker and therapeutic target for multiple neurodegenerative diseases, with clinical trials ongoing. The discovery of cis P-tau and other tau pathologies in VCID and PE calls attention for simplistic classification of tauopathy in neurodegenerative diseases. These recent advances have revealed the exciting novel role of the Pin1-cis P-tau axis in the development and treatment of vascular contribution to cognitive impairment and dementia and preeclampsia.
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Affiliation(s)
- Chenxi Qiu
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Zhixiong Li
- Departments of Biochemistry and Oncology, Schulich School of Medicine and Dentistry and Robarts Research Institute, Western University, London, ON, Canada
| | - David A. Leigh
- Department of Genetics, Harvard Medical School, Boston, MA, United States
| | - Bingbing Duan
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, United States
| | - Joseph E. Stucky
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Nami Kim
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - George Xie
- Departments of Biochemistry and Oncology, Schulich School of Medicine and Dentistry and Robarts Research Institute, Western University, London, ON, Canada
| | - Kun Ping Lu
- Departments of Biochemistry and Oncology, Schulich School of Medicine and Dentistry and Robarts Research Institute, Western University, London, ON, Canada
| | - Xiao Zhen Zhou
- Departments of Biochemistry and Oncology, Schulich School of Medicine and Dentistry and Robarts Research Institute, Western University, London, ON, Canada
- Departments of Pathology and Laboratory Medicine, Schulich School of Medicine and Dentistry, and Lawson Health Research Institute, Western University, London, ON, Canada
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5
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Zwick P, Troncossi A, Borsley S, Vitorica-Yrezabal IJ, Leigh DA. Stepwise Operation of a Molecular Rotary Motor Driven by an Appel Reaction. J Am Chem Soc 2024; 146:4467-4472. [PMID: 38319727 PMCID: PMC10885133 DOI: 10.1021/jacs.3c10266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
To date, only a small number of chemistries and chemical fueling strategies have been successfully used to operate artificial molecular motors. Here, we report the 360° directionally biased rotation of phenyl groups about a C-C bond, driven by a stepwise Appel reaction sequence. The motor molecule consists of a biaryl-embedded phosphine oxide and phenol, in which full rotation around the biaryl bond is blocked by the P-O oxygen atom on the rotor being too bulky to pass the oxygen atom on the stator. Treatment with SOCl2 forms a cyclic oxyphosphonium salt (removing the oxygen atom of the phosphine oxide), temporarily linking the rotor with the stator. Conformational exchange via ring flipping then allows the rotor and stator to twist back and forth past the previous limit of rotation. Subsequently, the ring opening of the tethered intermediate with a chiral alcohol occurs preferentially through a nucleophilic attack on one face. Thus, the original phosphine oxide is reformed with net directional rotation about the biaryl bond over the course of the two-step reaction sequence. Each repetition of SOCl2-chiral alcohol additions generates another directionally biased rotation. Using the same reaction sequence on a derivative of the motor molecule that forms atropisomers rather than fully rotating 360° results in enantioenrichment, suggesting that, on average, the motor molecule rotates in the "wrong" direction once every three fueling cycles. The interconversion of phosphine oxides and cyclic oxyphosphonium groups to form temporary tethers that enable a rotational barrier to be overcome directionally adds to the strategies available for generating chemically fueled kinetic asymmetry in molecular systems.
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Affiliation(s)
- Patrick Zwick
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Axel Troncossi
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Stefan Borsley
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | | | - David A Leigh
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
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6
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Borsley S, Gallagher JM, Leigh DA, Roberts BMW. Ratcheting synthesis. Nat Rev Chem 2024; 8:8-29. [PMID: 38102412 DOI: 10.1038/s41570-023-00558-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2023] [Indexed: 12/17/2023]
Abstract
Synthetic chemistry has traditionally relied on reactions between reactants of high chemical potential and transformations that proceed energetically downhill to either a global or local minimum (thermodynamic or kinetic control). Catalysts can be used to manipulate kinetic control, lowering activation energies to influence reaction outcomes. However, such chemistry is still constrained by the shape of one-dimensional reaction coordinates. Coupling synthesis to an orthogonal energy input can allow ratcheting of chemical reaction outcomes, reminiscent of the ways that molecular machines ratchet random thermal motion to bias conformational dynamics. This fundamentally distinct approach to synthesis allows multi-dimensional potential energy surfaces to be navigated, enabling reaction outcomes that cannot be achieved under conventional kinetic or thermodynamic control. In this Review, we discuss how ratcheted synthesis is ubiquitous throughout biology and consider how chemists might harness ratchet mechanisms to accelerate catalysis, drive chemical reactions uphill and programme complex reaction sequences.
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Affiliation(s)
- Stefan Borsley
- Department of Chemistry, University of Manchester, Manchester, UK
| | | | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, UK.
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7
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Baluna A, Dommaschk M, Groh B, Kassem S, Leigh DA, Tetlow DJ, Thomas D, Varela López L. Switched "On" Transient Fluorescence Output from a Pulsed-Fuel Molecular Ratchet. J Am Chem Soc 2023; 145:27113-27119. [PMID: 38047919 PMCID: PMC10722508 DOI: 10.1021/jacs.3c11290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/12/2023] [Accepted: 11/14/2023] [Indexed: 12/05/2023]
Abstract
We report the synthesis and operation of a molecular energy ratchet that transports a crown ether from solution onto a thread, along the axle, over a fluorophore, and off the other end of the thread back into bulk solution, all in response to a single pulse of a chemical fuel (CCl3CO2H). The fluorophore is a pyrene residue whose fluorescence is normally prevented by photoinduced electron transfer (PET) to a nearby N-methyltriazolium group. However, crown ether binding to the N-methyltriazolium site inhibits the PET, switching on pyrene fluorescence under UV irradiation. Each pulse of fuel results in a single ratchet cycle of transient fluorescence (encompassing threading, transport to the N-methyltriazolium site, and then dethreading), with the onset of the fluorescent time period determined by the amount of fuel in each pulse and the end-point determined by the concentration of the reagents for the disulfide exchange reaction. The system provides a potential alternative signaling approach for artificial molecular machines that read symbols from sequence-encoded molecular tapes.
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Affiliation(s)
- Andrei
S. Baluna
- Department of Chemistry, University
of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - Marcel Dommaschk
- Department of Chemistry, University
of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - Burkhard Groh
- Department of Chemistry, University
of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - Salma Kassem
- Department of Chemistry, University
of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - David A. Leigh
- Department of Chemistry, University
of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - Daniel J. Tetlow
- Department of Chemistry, University
of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - Dean Thomas
- Department of Chemistry, University
of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - Loli Varela López
- Department of Chemistry, University
of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
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8
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Abstract
We repeat the earliest claimed [2]catenane synthesis, reported by Wasserman over 60 years ago, in order to ascertain whether or not a nontemplate, statistical synthesis by acyloin macrocyclization does indeed form mechanically interlocked rings. The lack of direct experimental evidence for Wasserman's catenane has led to it being described as a "prophetic compound", a technical term used in patents for claimed molecules that have not yet been synthesized. Contemporary synthetic methods were used to reconstruct Wasserman's deuterium-labeled macrocycle and other building blocks on the 10-100 g reaction scale necessary to generate, in principle, ∼1 mg of catenane. Modern spectrometric and spectroscopic tools and chemical techniques (including tandem mass spectrometry, deuterium nuclear magnetic resonance (NMR) spectroscopy, and fluorescent tag labeling) were brought to bear in an effort to detect, isolate, and prove the structure of a putative [2]catenane consisting of a 34-membered cyclic hydrocarbon mechanically linked with a 34-membered cyclic α-hydroxyketone.
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Affiliation(s)
- Andrei S Baluna
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Albano Galan
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - David A Leigh
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
- School of Chemistry and Molecular Engineering, East China Normal University, 200062 Shanghai, China
| | - Gareth D Smith
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Justin T J Spence
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Daniel J Tetlow
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | | | - Min Zhang
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
- School of Chemistry and Molecular Engineering, East China Normal University, 200062 Shanghai, China
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9
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Power MJ, Morris DTJ, Vitorica-Yrezabal IJ, Leigh DA. Compact Rotaxane Superbases. J Am Chem Soc 2023. [PMID: 37039157 PMCID: PMC10119927 DOI: 10.1021/jacs.3c01202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
Abstract
Challenges for the development of efficacious new superbases include their ease of synthesis, chemical stability, and high basicity, while minimizing nucleophilicity is important for reducing unwanted side reactions. Here, we introduce a new family of organic superbases, compact amine-crown ether rotaxanes, which show desirable characteristics in all these respects. Metal-free active template synthesis provides access to a range of rotaxanes with as little as three atoms between the stoppering groups, locking the location of a small crown ether (21C7 and 24C8 derivatives) over the amine group of the axle. The forced proximity of the interlocked protophilic components results in pKaH+ values as high as 32.2 in acetonitrile, which is up to 13 pKaH+ units greater than the pKaH+ values of the non-interlocked components, and brings the free base rotaxanes into the basicity realm of phosphazene superbases. The rotaxane superbases are generally chemically stable and, in a model reaction for superbases, eliminate HBr from a primary alkyl bromide with complete selectivity for deprotonation over alkylation. Their modest size, ease of synthesis, high basicity, low nucleophilicity, and, in the best cases, rapid substrate deprotonation kinetics and excellent hydrolytic stability make compact amine-crown ether rotaxane superbases intriguing candidates for potential applications in synthesis and supramolecular and materials chemistry.
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Affiliation(s)
- Martin J Power
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - David T J Morris
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | | | - David A Leigh
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
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10
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Amano S, Esposito M, Kreidt E, Leigh DA, Penocchio E, Roberts BMW. Using Catalysis to Drive Chemistry Away from Equilibrium: Relating Kinetic Asymmetry, Power Strokes, and the Curtin–Hammett Principle in Brownian Ratchets. J Am Chem Soc 2022; 144:20153-20164. [DOI: 10.1021/jacs.2c08723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shuntaro Amano
- Department of Chemistry, University of Manchester, Oxford Road, ManchesterM13 9PL, United Kingdom
- Institute of Supramolecular Science and Engineering (ISIS), University of Strasbourg, 67000Strasbourg, France
| | - Massimiliano Esposito
- Department of Physics and Materials Science, University of Luxembourg, avenue de la Faïencerie, 1511Luxembourg City, G.D. Luxembourg
| | - Elisabeth Kreidt
- Department of Chemistry, University of Manchester, Oxford Road, ManchesterM13 9PL, United Kingdom
- Department of Chemistry and Chemical Biology, University of Dortmund, Otto-Hahn-Str. 6, 44227Dortmund, Germany
| | - David A. Leigh
- Department of Chemistry, University of Manchester, Oxford Road, ManchesterM13 9PL, United Kingdom
| | - Emanuele Penocchio
- Department of Physics and Materials Science, University of Luxembourg, avenue de la Faïencerie, 1511Luxembourg City, G.D. Luxembourg
- Department of Chemistry, Northwestern University, Evanston, Illinois60208, United States
| | - Benjamin M. W. Roberts
- Department of Chemistry, University of Manchester, Oxford Road, ManchesterM13 9PL, United Kingdom
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11
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Abstract
Cells process information in a manner reminiscent of a Turing machine1, autonomously reading data from molecular tapes and translating it into outputs2,3. Randomly processive macrocyclic catalysts that can derivatise threaded polymers have been described4,5, as have rotaxanes that transfer building blocks in sequence from a molecular strand to a growing oligomer6-10. However, synthetic small-molecule machines that can read and/or write information stored on artificial molecular tapes remain elusive11-13. Here we report on a molecular ratchet in which a crown ether (the 'reading head') is pumped from solution onto an encoded molecular strand (the 'tape') by a pulse14,15 of chemical fuel16. Further fuel pulses transport the macrocycle through a series of compartments of the tape via an energy ratchet14,17-22 mechanism, before releasing it back to bulk off the other end of the strand. During its directional transport, the crown ether changes conformation according to the stereochemistry of binding sites along the way. This allows the sequence of stereochemical information programmed into the tape to be read out as a string of digits in a non-destructive manner through a changing circular dichroism response. The concept is exemplified by the reading of molecular tapes with strings of balanced ternary digits ('trits'23), -1,0,+1 and -1,0,-1. The small-molecule ratchet is a finite-state automaton: a special case24 of a Turing machine that moves in one direction through a string-encoded state sequence, giving outputs dependent on the occupied machine state25,26. It opens the way for the reading-and ultimately writing-of information using the powered directional movement of artificial nanomachines along molecular tapes.
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Affiliation(s)
- Yansong Ren
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Romain Jamagne
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Daniel J Tetlow
- Department of Chemistry, University of Manchester, Manchester, UK
| | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, UK. .,School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China.
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12
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Abstract
Entangling strands in a well-ordered manner can produce useful effects, from shoelaces and fishing nets to brown paper packages tied up with strings. At the nanoscale, non-crystalline polymer chains of sufficient length and flexibility randomly form tangled mixtures containing open knots of different sizes, shapes and complexity. However, discrete molecular knots of precise topology can also be obtained by controlling the number, sequence and stereochemistry of strand crossings: orderly molecular entanglements. During the last decade, substantial progress in the nascent field of molecular nanotopology has been made, with general synthetic strategies and new knotting motifs introduced, along with insights into the properties and functions of ordered tangle sequences. Conformational restrictions imparted by knotting can induce allostery, strong and selective anion binding, catalytic activity, lead to effective chiral expression across length scales, binding modes in conformations efficacious for drug delivery, and facilitate mechanical function at the molecular level. As complex molecular topologies become increasingly synthetically accessible they have the potential to play a significant role in molecular and materials design strategies. We highlight particular examples of molecular knots to illustrate why these are a few of our favourite things.
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Affiliation(s)
- Zoe Ashbridge
- Department of Chemistry, The University of Manchester, Manchester, UK
| | | | - David A Leigh
- Department of Chemistry, The University of Manchester, Manchester, UK
- School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, China
| | - Lucian Pirvu
- Department of Chemistry, The University of Manchester, Manchester, UK
| | | | - Liang Zhang
- Department of Chemistry, The University of Manchester, Manchester, UK
- School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, China
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13
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Borsley S, Leigh DA, Roberts BMW, Vitorica-Yrezabal IJ. Tuning the Force, Speed, and Efficiency of an Autonomous Chemically Fueled Information Ratchet. J Am Chem Soc 2022; 144:17241-17248. [PMID: 36074864 PMCID: PMC9501901 DOI: 10.1021/jacs.2c07633] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Autonomous chemically fueled molecular machines that
function through
information ratchet mechanisms underpin the nonequilibrium processes
that sustain life. These biomolecular motors have evolved to be well-suited
to the tasks they perform. Synthetic systems that function through
similar mechanisms have recently been developed, and their minimalist
structures enable the influence of structural changes on machine performance
to be assessed. Here, we probe the effect of changes in the fuel and
barrier-forming species on the nonequilibrium operation of a carbodiimide-fueled
rotaxane-based information ratchet. We examine the machine’s
ability to catalyze the fuel-to-waste reaction and harness energy
from it to drive directional displacement of the macrocycle. These
characteristics are intrinsically linked to the speed, force, power,
and efficiency of the ratchet output. We find that, just as for biomolecular
motors and macroscopic machinery, optimization of one feature (such
as speed) can compromise other features (such as the force that can
be generated by the ratchet). Balancing speed, power, efficiency,
and directionality will likely prove important when developing artificial
molecular motors for particular applications.
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Affiliation(s)
- Stefan Borsley
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - David A Leigh
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.,School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Benjamin M W Roberts
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
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14
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Ashbridge Z, Knapp OM, Kreidt E, Leigh DA, Pirvu L, Schaufelberger F. Social Self-Sorting Synthesis of Molecular Knots. J Am Chem Soc 2022; 144:17232-17240. [PMID: 36067448 PMCID: PMC9501921 DOI: 10.1021/jacs.2c07682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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We report the synthesis of molecular prime and composite
knots
by social self-sorting of 2,6-pyridinedicarboxamide (pdc) ligands
of differing topicity and stereochemistry. Upon mixing achiral monotopic
and ditopic pdc-ligand strands in a 1:1:1 ratio with Lu(III), a well-defined
heteromeric complex featuring one of each ligand strand and the metal
ion is selectively formed. Introducing point-chiral centers into the
ligands leads to single-sense helical stereochemistry of the resulting
coordination complex. Covalent capture of the entangled structure
by ring-closing olefin metathesis then gives a socially self-sorted
trefoil knot of single topological handedness. In a related manner,
a heteromeric molecular granny knot (a six-crossing composite knot
featuring two trefoil tangles of the same handedness) was assembled
from social self-sorting of ditopic and tetratopic multi-pdc strands.
A molecular square knot (a six-crossing composite knot of two trefoil
tangles of opposite handedness) was assembled by social self-sorting
of a ditopic pdc strand with four (S)-centers and
a tetratopic strand with two (S)- and six (R)-centers. Each of the entangled structures was characterized
by 1H and 13C NMR spectroscopy, mass spectrometry,
and circular dichroism spectroscopy. The precise control of composition
and topological chirality through social self-sorting enables the
rapid assembly of well-defined sequences of entanglements for molecular
knots.
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Affiliation(s)
- Zoe Ashbridge
- Department of Chemistry, University of Manchester, Manchester M13 9PL, U.K
| | - Olivia M Knapp
- Department of Chemistry, University of Manchester, Manchester M13 9PL, U.K
| | - Elisabeth Kreidt
- Department of Chemistry, University of Manchester, Manchester M13 9PL, U.K
| | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester M13 9PL, U.K.,School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Lucian Pirvu
- Department of Chemistry, University of Manchester, Manchester M13 9PL, U.K
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15
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Abstract
We report a new class of synthetic molecular pumps that use a stepwise information ratchet mechanism to achieve the kinetic gating required to sequester their macrocyclic substrates from bulk solution. Threading occurs as a result of active template reactions between the pump terminus amine and an acyl electrophile, whereby the bond-forming reaction is accelerated through the cavity of a crown ether. Carboxylation of the resulting amide results in displacement of the ring to the collection region of the thread. Conversion of the carbamate to a phenolic ester provides an intermediate rotaxane suitable for further pumping cycles. In this way rings can be ratcheted onto a thread from one or both ends of appropriately designed molecular pumps. Each pumping cycle results in one additional ring being added to the thread per terminus acyl group. The absence of pseudorotaxane states ensures that no dethreading of intermediates occurs during the pump operation. This facilitates the loading of different macrocycles in any chosen sequence, illustrated by the pump-mediated synthesis of a [4]rotaxane containing three different macrocycles as a single sequence isomer. A [5]rotaxane synthesized using a dual-opening transamidation pump was structurally characterized by single-crystal X-ray diffraction, revealing a series of stabilizing CH···O interactions between the crown ethers and the polyethylene glycol catchment region of the thread.
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Affiliation(s)
- Lorna Binks
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Chong Tian
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Stephen D P Fielden
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | | | - David A Leigh
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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16
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Thomas D, Tetlow DJ, Ren Y, Kassem S, Karaca U, Leigh DA. Pumping between phases with a pulsed-fuel molecular ratchet. Nat Nanotechnol 2022; 17:701-707. [PMID: 35379944 DOI: 10.1038/s41565-022-01097-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 02/16/2022] [Indexed: 06/14/2023]
Abstract
The sorption of species from a solution into and onto solids underpins the sequestering of waste and pollutants, precious metal recovery, heterogeneous catalysis, analysis and separation science, and other technologies1,2. The transfer between phases tends to proceed spontaneously in the direction of equilibrium. For example, alkyl ammonium groups mounted on silica nanoparticles are used to chemisorb cucurbituril macrocycles from solution through host-guest binding3,4. Molecular ratchet mechanisms5-7, in which kinetic gating8-12 inhibits or accelerates particular steps, makes it possible to progressively drive dynamic systems13-16 away from equilibrium17-21. Here we report on molecular pumps22 immobilized on polymer beads23-25 that use an energy ratchet mechanism5,9,19-21,26-30 to directionally transport substrates from solution onto the beads. On the addition of trichloroacetic acid (CCl3CO2H)19,31-33 fuel19,34-37, micrometre-diameter polystyrene beads functionalized38 with solvent-accessible molecular pumps sequester from the solution crown ethers appended with fluorescent tags. After fuel consumption, the rings are mechanically trapped in a higher-energy, out-of-equilibrium state on the beads and cannot be removed by dilution or exhaustive washing. This differs from dissipative assembled materials11,13-16, which require a continuous supply of energy to persist, and from conventional host-guest complexes. The addition of a second fuel pulse causes the uptake of more macrocycles, which drives the system further away from equilibrium. The second macrocycle can be labelled with a different fluorescent tag, which confers sequence information39 on the absorbed structure. The polymer-bound substrates can be released back to the bulk either one compartment at a time or all at once. Non-equilibrium40 sorption by immobilized artificial molecular machines41-45 enables the transduction of energy from chemical fuels for the use, storage and release of energy and information.
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Affiliation(s)
- Dean Thomas
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Daniel J Tetlow
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Yansong Ren
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Salma Kassem
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Ulvi Karaca
- Department of Chemistry, University of Manchester, Manchester, UK
| | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, UK.
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China.
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17
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Abstract
Chemical reaction networks that transform out-of-equilibrium 'fuel' to 'waste' are the engines that power the biomolecular machinery of the cell. Inspired by such systems, autonomous artificial molecular machinery is being developed that functions by catalysing the decomposition of chemical fuels, exploiting kinetic asymmetry to harness energy released from the fuel-to-waste reaction to drive non-equilibrium structures and dynamics. Different aspects of chemical fuels profoundly influence their ability to power molecular machines. Here we consider the structure and properties of the fuels that biology has evolved and compare their features with those of the rudimentary synthetic chemical fuels that have so far been used to drive autonomous non-equilibrium molecular-level dynamics. We identify desirable, but context-specific, traits for chemical fuels together with challenges and opportunities for the design and invention of new chemical fuels to power synthetic molecular machinery and other dissipative nanoscale processes.
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Affiliation(s)
- Stefan Borsley
- Department of Chemistry, University of Manchester, Manchester, UK
| | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, UK.
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18
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Asthana D, Thomas D, Lockyer SJ, Brookfield A, Timco GA, Vitorica-Yrezabal IJ, Whitehead GFS, McInnes EJL, Collison D, Leigh DA, Winpenny REP. Decorating polymer beads with 10 14 inorganic-organic [2]rotaxanes as shown by spin counting. Commun Chem 2022; 5:73. [PMID: 36697699 PMCID: PMC9814693 DOI: 10.1038/s42004-022-00689-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 05/27/2022] [Indexed: 01/28/2023] Open
Abstract
Polymer beads have been used as the core of magnetic particles for around twenty years. Here we report studies to attach polymetallic complexes to polymer beads for the first time, producing beads of around 115 microns diameter that are attached to 1014 hybrid inorganic-organic [2]rotaxanes. The bead is then formally a [1014] rotaxane. The number of complexes attached is counted by EPR spectroscopy after including TEMPO radicals within the thread of the hybrid [2]rotaxanes.
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Affiliation(s)
- Deepak Asthana
- grid.5379.80000000121662407Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9Pl UK ,grid.449178.70000 0004 5894 7096Department of Chemistry, Ashoka University, Sonipat, Haryana India
| | - Dean Thomas
- grid.5379.80000000121662407Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9Pl UK
| | - Selena J. Lockyer
- grid.5379.80000000121662407Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9Pl UK
| | - Adam Brookfield
- grid.5379.80000000121662407Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9Pl UK
| | - Grigore A. Timco
- grid.5379.80000000121662407Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9Pl UK
| | - Iñigo J. Vitorica-Yrezabal
- grid.5379.80000000121662407Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9Pl UK
| | - George F. S. Whitehead
- grid.5379.80000000121662407Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9Pl UK
| | - Eric J. L. McInnes
- grid.5379.80000000121662407Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9Pl UK
| | - David Collison
- grid.5379.80000000121662407Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9Pl UK
| | - David A. Leigh
- grid.5379.80000000121662407Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9Pl UK
| | - Richard E. P. Winpenny
- grid.5379.80000000121662407Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9Pl UK
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19
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Borsley S, Kreidt E, Leigh DA, Roberts BMW. Autonomous fuelled directional rotation about a covalent single bond. Nature 2022; 604:80-85. [PMID: 35388198 DOI: 10.1038/s41586-022-04450-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/20/2022] [Indexed: 11/09/2022]
Abstract
Biology operates through autonomous chemically fuelled molecular machinery1, including rotary motors such as adenosine triphosphate synthase2 and the bacterial flagellar motor3. Chemists have long sought to create analogous molecular structures with chemically powered, directionally rotating, components4-17. However, synthetic motor molecules capable of autonomous 360° directional rotation about a single bond have proved elusive, with previous designs lacking either autonomous fuelling7,10,12 or directionality6. Here we show that 1-phenylpyrrole 2,2'-dicarboxylic acid18,19 (1a) is a catalysis-driven20,21 motor that can continuously transduce energy from a chemical fuel9,20-27 to induce repetitive 360° directional rotation of the two aromatic rings around the covalent N-C bond that connects them. On treatment of 1a with a carbodiimide21,25-27, intramolecular anhydride formation between the rings and the anhydride's hydrolysis both occur incessantly. Both reactions are kinetically gated28-30 causing directional bias. Accordingly, catalysis of carbodiimide hydration by the motor molecule continuously drives net directional rotation around the N-C bond. The directionality is determined by the handedness of both an additive that accelerates anhydride hydrolysis and that of the fuel, and is easily reversed additive31. More than 97% of fuel molecules are consumed through the chemical engine cycle24 with a directional bias of up to 71:29 with a chirality-matched fuel and additive. In other words, the motor makes a 'mistake' in direction every three to four turns. The 26-atom motor molecule's simplicity augurs well for its structural optimization and the development of derivatives that can be interfaced with other components for the performance of work and tasks32-36.
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Affiliation(s)
- Stefan Borsley
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Elisabeth Kreidt
- Department of Chemistry, University of Manchester, Manchester, UK
| | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, UK. .,School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China.
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20
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Amano S, Esposito M, Kreidt E, Leigh DA, Penocchio E, Roberts BMW. Insights from an information thermodynamics analysis of a synthetic molecular motor. Nat Chem 2022; 14:530-537. [PMID: 35301472 DOI: 10.1038/s41557-022-00899-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 01/28/2022] [Indexed: 12/11/2022]
Abstract
Information is physical, a realization that has transformed the physics of measurement and communication. However, the flow between information, energy and mechanics in chemical systems remains largely unexplored. Here we analyse a minimalist autonomous chemically driven molecular motor in terms of information thermodynamics, a framework that quantitatively relates information to other thermodynamic parameters. The treatment reveals how directional motion is generated by free energy transfer from chemical to mechanical (conformational and/or co-conformational) processes by 'energy flow' and 'information flow'. It provides a thermodynamic level of understanding of molecular motors that is general, complements previous analyses based on kinetics and has practical implications for machine design. In line with kinetic analysis, we find that power strokes do not affect the directionality of chemically driven machines. However, we find that power strokes can modulate motor velocity, the efficiency of free energy transfer and the number of fuel molecules consumed per cycle. This may help explain the role of such (co-)conformational changes in biomachines and illustrates the interplay between energy and information in chemical systems.
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Affiliation(s)
- Shuntaro Amano
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Massimiliano Esposito
- Department of Physics and Materials Science, University of Luxembourg, Luxembourg City, Luxembourg
| | - Elisabeth Kreidt
- Department of Chemistry, University of Manchester, Manchester, UK
| | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, UK.
| | - Emanuele Penocchio
- Department of Physics and Materials Science, University of Luxembourg, Luxembourg City, Luxembourg.
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21
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Abstract
Molecular knots are often prepared using metal helicates to cross the strands. We found that coordinatively mismatching oligodentate ligands and metal ions provides a more effective way to synthesize larger knots using Vernier templating. Strands composed of different numbers of tridentate 2,6-pyridinedicarboxamide groups fold around nine-coordinate lanthanide (III) ions to generate strand-entangled complexes with the lowest common multiple of coordination sites for the ligand strands and metal ions. Ring-closing olefin metathesis then completes the knots. A 3:2 (ditopic strand:metal) Vernier assembly produces +31#+31 and -31#-31 granny knots. Vernier complexes of 3:4 (tetratopic strand:metal) stoichiometry selectively form a 378-atom-long trefoil-of-trefoils triskelion knot with 12 alternating strand crossings or, by using opposing stereochemistry at the terminus of the strand, an inverted-core triskelion knot with six alternating and six nonalternating strand crossings.
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Affiliation(s)
- Zoe Ashbridge
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Elisabeth Kreidt
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Lucian Pirvu
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | | | - Joakim Halldin Stenlid
- SUNCAT Center for Interface Science and Catalysis, Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA.,SUNCAT Center for Interface Science and Catalysis, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Frank Abild-Pedersen
- SUNCAT Center for Interface Science and Catalysis, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - David A Leigh
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK.,School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
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22
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Abstract
Historically, the interlacing of strands at the molecular level has mainly been limited to coordination polymers and DNA. Despite being proposed on a number of occasions, the direct, bottom-up assembly of molecular building blocks into woven organic polymers remained an aspirational, but elusive, target for several decades. However, recent successes in two-dimensional and three-dimensional molecular-level weaving now offer new opportunities and research directions at the interface of polymer science and molecular nanotopology. This Perspective provides an overview of the features and potential of the periodic nanoscale weaving of polymer chains, distinguishing it from randomly entangled polymer networks and rigid crystalline frameworks. We review the background and experimental progress so far, and conclude by considering the potential of molecular weaving and outline some of the current and future challenges in this emerging field.
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Affiliation(s)
- Zhi-Hui Zhang
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China
| | | | - David P August
- Department of Chemistry, University of Manchester, Manchester, UK
| | - David A Leigh
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China.
- Department of Chemistry, University of Manchester, Manchester, UK.
| | - Liang Zhang
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China.
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23
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Chen S, Su D, Jia C, Li Y, Li X, Guo X, Leigh DA, Zhang L. Real-time observation of the dynamics of an individual rotaxane molecular shuttle using a single-molecule junction. Chem 2022. [DOI: 10.1016/j.chempr.2021.11.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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24
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Amano S, Borsley S, Leigh DA, Sun Z. Chemical engines: driving systems away from equilibrium through catalyst reaction cycles. Nat Nanotechnol 2021; 16:1057-1067. [PMID: 34625723 DOI: 10.1038/s41565-021-00975-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 08/03/2021] [Indexed: 06/13/2023]
Abstract
Biological systems exhibit a range of complex functions at the micro- and nanoscales under non-equilibrium conditions (for example, transportation and motility, temporal control, information processing and so on). Chemists also employ out-of-equilibrium systems, for example in kinetic selection during catalysis, self-replication, dissipative self-assembly and synthetic molecular machinery, and in the form of chemical oscillators. Key to non-equilibrium behaviour are the mechanisms through which systems are able to extract energy from the chemical reactants ('fuel') that drive such processes. In this Perspective we relate different examples of such powering mechanisms using a common conceptual framework. We discuss how reaction cycles can be coupled to other dynamic processes through positive (acceleration) or negative (inhibition) catalysis to provide the thermodynamic impetus for diverse non-equilibrium behaviour, in effect acting as a 'chemical engine'. We explore the way in which the energy released from reaction cycles is harnessed through kinetic selection in a series of what have sometimes been considered somewhat disparate fields (systems chemistry, molecular machinery, dissipative assembly and chemical oscillators), highlight common mechanistic principles and the potential for the synchronization of chemical reaction cycles, and identify future challenges for the invention and application of non-equilibrium systems. Explicit recognition of the use of fuelling reactions to power structural change in catalysts may stimulate the investigation of known catalytic cycles as potential elements for chemical engines, a currently unexplored area of catalysis research.
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Affiliation(s)
- Shuntaro Amano
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Stefan Borsley
- Department of Chemistry, University of Manchester, Manchester, UK
| | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, UK.
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China.
| | - Zhanhu Sun
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China
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25
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Echavarren J, Gall MAY, Haertsch A, Leigh DA, Spence JTJ, Tetlow DJ, Tian C. Sequence-Selective Decapeptide Synthesis by the Parallel Operation of Two Artificial Molecular Machines. J Am Chem Soc 2021; 143:5158-5165. [PMID: 33764775 DOI: 10.1021/jacs.1c01234] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We report on the preparation of a decapeptide through the parallel operation of two rotaxane-based molecular machines. The synthesis proceeds in four stages: (1) simultaneous operation of two molecular peptide synthesizers in the same reaction vessel; (2) selective residue activation of short-oligomer intermediates; (3) ligation; (4) product release. Key features of the machine design include the following: (a) selective transformation of a thioproline building block to a cysteine (once it has been incorporated into a hexapeptide intermediate by one molecular machine); (b) a macrocycle-peptide hydrazine linkage (as part of the second machine) to differentiate the intermediates and enable their directional ligation; and (c) incorporation of a Glu residue in the assembly module of one machine to enable release of the final product while simultaneously removing part of the assembly machinery from the product. The two molecular machines participate in the synthesis of a product that is beyond the capability of individual small-molecule machines, in a manner reminiscent of the ligation and post-translational modification of proteins in biology.
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Affiliation(s)
- Javier Echavarren
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Malcolm A Y Gall
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Adrian Haertsch
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - David A Leigh
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Justin T J Spence
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Daniel J Tetlow
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Chong Tian
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
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26
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Borsley S, Leigh DA, Roberts BMW. A Doubly Kinetically-Gated Information Ratchet Autonomously Driven by Carbodiimide Hydration. J Am Chem Soc 2021; 143:4414-4420. [DOI: 10.1021/jacs.1c01172] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Stefan Borsley
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - David A. Leigh
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Benjamin M. W. Roberts
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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27
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Sluysmans D, Lussis P, Fustin CA, Bertocco A, Leigh DA, Duwez AS. Real-Time Fluctuations in Single-Molecule Rotaxane Experiments Reveal an Intermediate Weak Binding State during Shuttling. J Am Chem Soc 2021; 143:2348-2352. [PMID: 33417442 DOI: 10.1021/jacs.0c12161] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We report on the use of atomic force microscopy (AFM) to identify and characterize an intermediate state in macrocycle shuttling in a hydrogen bonded amide-based molecular shuttle. The [2]rotaxane consists of a benzylic amide macrocycle mechanically locked onto a thread that bears both fumaramide and succinic amide-ester sites, each of which can bind to the macrocycle through up to four intercomponent hydrogen bonds. Using AFM-based single-molecule force spectroscopy, we mechanically triggered the translocation of the ring between the two principal binding sites ("stations") on the axle. Equilibrium fluctuations reveal another interacting site involving the two oxygen atoms in the middle of the thread. We characterized the ring occupancy distribution over time, which confirms the intermediate in both shuttling directions. The study provides evidence of weak hydrogen bonds that are difficult to detect using other methods and shows how the composition of the thread can significantly influence the shuttling dynamics by slowing down the ring motion between the principal binding sites. More generally, the study illustrates the utility that single-molecule experiments, such as force spectroscopy, can offer for elucidating the structure and dynamics of synthetic molecular machines.
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Affiliation(s)
- Damien Sluysmans
- UR MolSys, University of Liege, Sart-Tilman, B6a, 4000 Liege, Belgium
| | - Perrine Lussis
- UR MolSys, University of Liege, Sart-Tilman, B6a, 4000 Liege, Belgium
| | - Charles-André Fustin
- Bio and Soft Matter Division (BSMA), Institute of Condensed Matter and Nanosciences (IMCN), Université catholique de Louvain, Place L. Pasteur 1 and Croix du Sud 1, Louvain-la-Neuve B-1348, Belgium
| | - Andrea Bertocco
- Department of Chemistry, University of Manchester, Manchester M13 9PL, United Kingdom
| | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Anne-Sophie Duwez
- UR MolSys, University of Liege, Sart-Tilman, B6a, 4000 Liege, Belgium
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28
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Leigh DA, Danon JJ, Fielden SDP, Lemonnier JF, Whitehead GFS, Woltering SL. A molecular endless (7 4) knot. Nat Chem 2021; 13:117-122. [PMID: 33318672 DOI: 10.1038/s41557-020-00594-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 10/23/2020] [Indexed: 01/30/2023]
Abstract
Current strategies for the synthesis of molecular knots focus on twisting, folding and/or threading molecular building blocks. Here we report that Zn(II) or Fe(II) ions can be used to weave ligand strands to form a woven 3 × 3 molecular grid. We found that the process requires tetrafluoroborate anions to template the assembly of the interwoven grid by binding within the square cavities formed between the metal-coordinated criss-crossed ligands. The strand ends of the grid can subsequently be joined through within-grid alkene metathesis reactions to form a topologically trivial macrocycle (unknot), a doubly interlocked [2]catenane (Solomon link) and a knot with seven crossings in a 258-atom-long closed loop. This 74 knot topology corresponds to that of an endless knot, which is a basic motif of Celtic interlace, the smallest Chinese knot and one of the eight auspicious symbols of Buddhism and Hinduism. The weaving of molecular strands within a discrete layer by anion-template metal-ion coordination opens the way for the synthesis of other molecular knot topologies and to woven polymer materials.
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Affiliation(s)
- David A Leigh
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China. .,Department of Chemistry, University of Manchester, Manchester, UK.
| | - Jonathan J Danon
- Department of Chemistry, University of Manchester, Manchester, UK
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29
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August DP, Jaramillo-Garcia J, Leigh DA, Valero A, Vitorica-Yrezabal IJ. A Chiral Cyclometalated Iridium Star of David [2]Catenane. J Am Chem Soc 2021; 143:1154-1161. [DOI: 10.1021/jacs.0c12038] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- David P. August
- Department of Chemistry, University of Manchester, Manchester M13 9PL, United Kingdom
| | | | - David A. Leigh
- Department of Chemistry, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Alberto Valero
- Department of Chemistry, University of Manchester, Manchester M13 9PL, United Kingdom
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30
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August DP, Dryfe RAW, Haigh SJ, Kent PRC, Leigh DA, Lemonnier JF, Li Z, Muryn CA, Palmer LI, Song Y, Whitehead GFS, Young RJ. Self-assembly of a layered two-dimensional molecularly woven fabric. Nature 2020; 588:429-435. [PMID: 33328664 DOI: 10.1038/s41586-020-3019-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 10/28/2020] [Indexed: 12/18/2022]
Abstract
Fabrics-materials consisting of layers of woven fibres-are some of the most important materials in everyday life1. Previous nanoscale weaves2-16 include isotropic crystalline covalent organic frameworks12-14 that feature rigid helical strands interlaced in all three dimensions, rather than the two-dimensional17,18 layers of flexible woven strands that give conventional textiles their characteristic flexibility, thinness, anisotropic strength and porosity. A supramolecular two-dimensional kagome weave15 and a single-layer, surface-supported, interwoven two-dimensional polymer16 have also been reported. The direct, bottom-up assembly of molecular building blocks into linear organic polymer chains woven in two dimensions has been proposed on a number of occasions19-23, but has not previously been achieved. Here we demonstrate that by using an anion and metal ion template, woven molecular 'tiles' can be tessellated into a material consisting of alternating aliphatic and aromatic segmented polymer strands, interwoven within discrete layers. Connections between slowly precipitating pre-woven grids, followed by the removal of the ion template, result in a wholly organic molecular material that forms as stacks and clusters of thin sheets-each sheet up to hundreds of micrometres long and wide but only about four nanometres thick-in which warp and weft single-chain polymer strands remain associated through periodic mechanical entanglements within each sheet. Atomic force microscopy and scanning electron microscopy show clusters and, occasionally, isolated individual sheets that, following demetallation, have slid apart from others with which they were stacked during the tessellation and polymerization process. The layered two-dimensional molecularly woven material has long-range order, is birefringent, is twice as stiff as the constituent linear polymer, and delaminates and tears along well-defined lines in the manner of a macroscopic textile. When incorporated into a polymer-supported membrane, it acts as a net, slowing the passage of large ions while letting smaller ions through.
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Affiliation(s)
- David P August
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Robert A W Dryfe
- Department of Chemistry, University of Manchester, Manchester, UK.,Henry Royce Institute, University of Manchester, Manchester, UK
| | - Sarah J Haigh
- Department of Materials, National Graphene Institute, University of Manchester, Manchester, UK
| | - Paige R C Kent
- Department of Chemistry, University of Manchester, Manchester, UK
| | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, UK.
| | | | - Zheling Li
- Department of Materials, National Graphene Institute, University of Manchester, Manchester, UK
| | | | - Leoni I Palmer
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Yiwei Song
- Department of Chemistry, University of Manchester, Manchester, UK
| | | | - Robert J Young
- Department of Materials, National Graphene Institute, University of Manchester, Manchester, UK
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31
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Kassem S, Lee ATL, Leigh DA, Markevicius A, Tetlow DJ, Toriumi N. Site-to-site peptide transport on a molecular platform using a small-molecule robotic arm. Chem Sci 2020; 12:2065-2070. [PMID: 34163969 PMCID: PMC8179245 DOI: 10.1039/d0sc05906d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Peptides attached to a cysteine hydrazide ‘transporter module’ are transported selectively in either direction between two chemically similar sites on a molecular platform, enabled by the discovery of new operating methods for a molecular transporter that functions through ratcheting. Substrate repositioning is achieved using a small-molecule robotic arm controlled by a protonation-mediated rotary switch and attachment/release dynamic covalent chemistry. A polar solvent mixtures were found to favour Z to E isomerization of the doubly-protonated switch, transporting cargo in one direction (arbitrarily defined as ‘forward’) in up to 85% yield, while polar solvent mixtures were unexpectedly found to favour E to Z isomerization enabling transport in the reverse (‘backward’) direction in >98% yield. Transport of the substrates proceeded in a matter of hours (compared to 6 days even for simple cargoes with the original system) without the peptides at any time dissociating from the machine nor exchanging with others in the bulk. Under the new operating conditions, key intermediates of the switch are sufficiently stabilized within the macrocycle formed between switch, arm, substrate and platform that they can be identified and structurally characterized by 1H NMR. The size of the peptide cargo has no significant effect on the rate or efficiency of transport in either direction. The new operating conditions allow detailed physical organic chemistry of the ratcheted transport mechanism to be uncovered, improve efficiency, and enable the transport of more complex cargoes than was previously possible. Peptides are transported in either direction between chemically similar sites on a molecular platform, substrate repositioning is achieved using a cysteine hydrazide transporter module and a small-molecule robotic arm controlled by a rotary switch.![]()
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Affiliation(s)
- Salma Kassem
- Department of Chemistry, University of Manchester Oxford Road Manchester M13 9PL UK
| | - Alan T L Lee
- Department of Chemistry, University of Manchester Oxford Road Manchester M13 9PL UK
| | - David A Leigh
- Department of Chemistry, University of Manchester Oxford Road Manchester M13 9PL UK
| | | | - Daniel J Tetlow
- Department of Chemistry, University of Manchester Oxford Road Manchester M13 9PL UK
| | - Naoyuki Toriumi
- Department of Chemistry, University of Manchester Oxford Road Manchester M13 9PL UK
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32
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Song Y, Schaufelberger F, Ashbridge Z, Pirvu L, Vitorica-Yrezabal IJ, Leigh DA. Effects of turn-structure on folding and entanglement in artificial molecular overhand knots. Chem Sci 2020; 12:1826-1833. [PMID: 34163946 PMCID: PMC8179330 DOI: 10.1039/d0sc05897a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The length and constitution of spacers linking three 2,6-pyridinedicarboxamide units in a molecular strand influence the tightness of the resulting overhand (open-trefoil) knot that the strand folds into in the presence of lanthanide(iii) ions. The use of β-hairpin forming motifs as linkers enables a metal-coordinated pseudopeptide with a knotted tertiary structure to be generated. The resulting pseudopeptide knot has one of the highest backbone-to-crossing ratios (BCR)—a measure of knot tightness (a high value corresponding to looseness)—for a synthetic molecular knot to date. Preorganization in the crossing-free turn section of the knot affects aromatic stacking interactions close to the crossing region. The metal-coordinated pseudopeptide knot is compared to overhand knots with other linkers of varying tightness and turn preorganization, and the entangled architectures characterized by NMR spectroscopy, ESI-MS, CD spectroscopy and, in one case, X-ray crystallography. The results show how it is possible to program specific conformational properties into different key regions of synthetic molecular knots, opening the way to systems where knotting can be systematically incorporated into peptide-like chains through design. Spacers linking 2,6-pyridinedicarboxamide units influence the tightness of the corresponding lanthanide-coordinated overhand knot. β-Hairpin forming motifs generate a metal-coordinated pseudopeptide with a knotted tertiary structure.![]()
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Affiliation(s)
- Yiwei Song
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University Shanghai 200062 PR China
| | | | - Zoe Ashbridge
- Department of Chemistry, University of Manchester Oxford Road Manchester M13 9PL UK
| | - Lucian Pirvu
- Department of Chemistry, University of Manchester Oxford Road Manchester M13 9PL UK
| | | | - David A Leigh
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University Shanghai 200062 PR China .,Department of Chemistry, University of Manchester Oxford Road Manchester M13 9PL UK
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33
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August DP, Borsley S, Cockroft SL, Della Sala F, Leigh DA, Webb SJ. Transmembrane Ion Channels Formed by a Star of David [2]Catenane and a Molecular Pentafoil Knot. J Am Chem Soc 2020; 142:18859-18865. [PMID: 33084320 PMCID: PMC7745878 DOI: 10.1021/jacs.0c07977] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A (FeII)6-coordinated triply interlocked ("Star of David") [2]catenane (612 link) and a (FeII)5-coordinated pentafoil (51) knot are found to selectively transport anions across phospholipid bilayers. Allostery, topology, and building block stoichiometry all play important roles in the efficacy of the ionophoric activity. Multiple FeII cation coordination by the interlocked molecules is crucial: the demetalated catenane exhibits no anion binding in solution nor any transmembrane ion transport properties. However, the topologically trivial, Lehn-type cyclic hexameric FeII helicates-which have similar anion binding affinities to the metalated Star of David catenane in solution-also display no ion transport properties. The unanticipated difference in behavior between the open- and closed-loop structures may arise from conformational restrictions in the linking groups that likely enhances the rigidity of the channel-forming topologically complex molecules. The (FeII)6-coordinated Star of David catenane, derived from a hexameric cyclic helicate, is 2 orders of magnitude more potent in terms of ion transport than the (FeII)5-coordinated pentafoil knot, derived from a cyclic pentamer of the same building block. The reduced efficacy is reminiscent of multisubunit protein ion channels assembled with incorrect monomer stoichiometries.
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Affiliation(s)
- David P August
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Stefan Borsley
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Scott L Cockroft
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, United Kingdom
| | - Flavio Della Sala
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom.,Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - David A Leigh
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Simon J Webb
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom.,Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
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34
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Katsonis N, Lancia F, Leigh DA, Pirvu L, Ryabchun A, Schaufelberger F. Knotting a molecular strand can invert macroscopic effects of chirality. Nat Chem 2020; 12:939-944. [DOI: 10.1038/s41557-020-0517-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 06/25/2020] [Indexed: 11/10/2022]
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35
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Tian C, Fielden SDP, Pérez-Saavedra B, Vitorica-Yrezabal IJ, Leigh DA. Single-Step Enantioselective Synthesis of Mechanically Planar Chiral [2]Rotaxanes Using a Chiral Leaving Group Strategy. J Am Chem Soc 2020; 142:9803-9808. [PMID: 32356978 PMCID: PMC7266371 DOI: 10.1021/jacs.0c03447] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
![]()
We report a one-step
enantioselective synthesis of mechanically
planar chiral [2]rotaxanes. Previous studies of such molecules have
generally involved the separation of enantiomers from racemic mixtures
or the preparation and separation of diastereomeric intermediates
followed by post-assembly modification to remove other sources of
chirality. Here, we demonstrate a simple asymmetric metal-free active
template rotaxane synthesis using a primary amine, an activated ester
with a chiral leaving group, and an achiral crown ether lacking rotational
symmetry. Mechanically planar chiral rotaxanes are obtained directly
in up to 50% enantiomeric excess. The rotaxanes were characterized
by NMR spectroscopy, high-resolution mass spectrometry, chiral HPLC,
single crystal X-ray diffraction, and circular dichroism. Either rotaxane
enantiomer could be prepared selectively by incorporating pseudoenantiomeric
cinchona alkaloids into the chiral leaving group.
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Affiliation(s)
- Chong Tian
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Stephen D P Fielden
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Borja Pérez-Saavedra
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | | | - David A Leigh
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom.,School of Chemistry and Molecular Engineering, East China Normal University, 200062 Shanghai, China
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36
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Tian C, Fielden SDP, Whitehead GFS, Vitorica-Yrezabal IJ, Leigh DA. Weak functional group interactions revealed through metal-free active template rotaxane synthesis. Nat Commun 2020; 11:744. [PMID: 32029725 PMCID: PMC7005292 DOI: 10.1038/s41467-020-14576-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 01/08/2020] [Indexed: 11/24/2022] Open
Abstract
Modest functional group interactions can play important roles in molecular recognition, catalysis and self-assembly. However, weakly associated binding motifs are often difficult to characterize. Here, we report on the metal-free active template synthesis of [2]rotaxanes in one step, up to 95% yield and >100:1 rotaxane:axle selectivity, from primary amines, crown ethers and a range of C=O, C=S, S(=O)2 and P=O electrophiles. In addition to being a simple and effective route to a broad range of rotaxanes, the strategy enables 1:1 interactions of crown ethers with various functional groups to be characterized in solution and the solid state, several of which are too weak - or are disfavored compared to other binding modes - to be observed in typical host-guest complexes. The approach may be broadly applicable to the kinetic stabilization and characterization of other weak functional group interactions.
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Affiliation(s)
- Chong Tian
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK
| | | | | | | | - David A Leigh
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK.
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37
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Dommaschk M, Echavarren J, Leigh DA, Marcos V, Singleton TA. Dynamic Control of Chiral Space Through Local Symmetry Breaking in a Rotaxane Organocatalyst. Angew Chem Int Ed Engl 2019; 58:14955-14958. [PMID: 31454135 DOI: 10.1002/anie.201908330] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Indexed: 12/21/2022]
Abstract
We report on a switchable rotaxane molecular shuttle that features a pseudo-meso 2,5-disubstituted pyrrolidine catalytic unit on the axle whose local symmetry is broken according to the position of a threaded benzylic amide macrocycle. The macrocycle can be selectively switched (with light in one direction; with catalytic acid in the other) with high fidelity between binding sites located to either side of the pyrrolidine unit. The position of the macrocycle dictates the facial bias of the rotaxane-catalyzed conjugate addition of aldehydes to vinyl sulfones. The pseudo-meso non-interlocked thread does not afford significant selectivity as a catalyst (2-14 % ee), whereas the rotaxane affords selectivities of up to 40 % ee with switching of the position of the macrocycle changing the handedness of the product formed (up to 60 % Δee).
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Affiliation(s)
- Marcel Dommaschk
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Javier Echavarren
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - David A Leigh
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Vanesa Marcos
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Thomas A Singleton
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
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38
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Dommaschk M, Echavarren J, Leigh DA, Marcos V, Singleton TA. Dynamic Control of Chiral Space Through Local Symmetry Breaking in a Rotaxane Organocatalyst. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201908330] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Marcel Dommaschk
- School of Chemistry University of Manchester Oxford Road Manchester M13 9PL UK
| | - Javier Echavarren
- School of Chemistry University of Manchester Oxford Road Manchester M13 9PL UK
| | - David A. Leigh
- School of Chemistry University of Manchester Oxford Road Manchester M13 9PL UK
| | - Vanesa Marcos
- School of Chemistry University of Manchester Oxford Road Manchester M13 9PL UK
| | - Thomas A. Singleton
- School of Chemistry University of Manchester Oxford Road Manchester M13 9PL UK
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39
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Abstract
We report on the stereoselective synthesis of trefoil knots of single topological handedness in up to 90% yield (over two steps) through the formation of trimeric circular helicates from ligand strands containing either imine or, unexpectedly, amide chelating units and metal ion templates of the appropriate coordination character (zinc(II) for imines; cobalt(III) for amides). The coordination stereochemistry of the octahedral metal complexes is determined by asymmetric carbon centers in the strands, ultimately translating into trefoil knots that are a single enantiomer, both physically and in terms of their fundamental topology. Both the imine-zinc and amide-cobalt systems display self-sorting behavior, with racemic ligands forming knots that individually contain only building blocks of the same chirality. The knots and the corresponding trimeric circular helicate intermediates (Zn(II)3 complex for the imine ligands; Co(III)3 complex for the amide ligands) were characterized by nuclear magnetic resonance spectroscopy, mass spectrometry, and X-ray crystallography. The latter confirms the trefoil knots as 84-membered macrocycles, with each of the metal ions sited at a crossing point for three regions of the strand. The stereochemistry of the octahedral coordination centers imparts alternating crossings of the same handedness within each circular helicate. The expression of chirality of the knotted molecules was probed by circular dichroism: The topological handedness of the demetalated knots was found to have a greater effect on the CD response than the Euclidean chirality of an individual chiral center.
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Affiliation(s)
- Jiankang Zhong
- School of Chemistry , University of Manchester , Manchester M13 9PL , United Kingdom
| | - Liang Zhang
- School of Chemistry and Molecular Engineering , East China Normal University , 200062 Shanghai , China.,School of Chemistry , University of Manchester , Manchester M13 9PL , United Kingdom
| | - David P August
- School of Chemistry , University of Manchester , Manchester M13 9PL , United Kingdom
| | - George F S Whitehead
- School of Chemistry , University of Manchester , Manchester M13 9PL , United Kingdom
| | - David A Leigh
- School of Chemistry and Molecular Engineering , East China Normal University , 200062 Shanghai , China.,School of Chemistry , University of Manchester , Manchester M13 9PL , United Kingdom
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40
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Echavarren J, Gall MAY, Haertsch A, Leigh DA, Marcos V, Tetlow DJ. Active template rotaxane synthesis through the Ni-catalyzed cross-coupling of alkylzinc reagents with redox-active esters. Chem Sci 2019; 10:7269-7273. [PMID: 31588296 PMCID: PMC6686731 DOI: 10.1039/c9sc02457c] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Accepted: 06/15/2019] [Indexed: 12/24/2022] Open
Abstract
The synthesis of unsymmetrical axle [2]rotaxanes through a recently developed Ni-catalyzed C(sp3)-C(sp3) cross-coupling of redox-active esters (formed directly from carboxylic acids) and organozinc reagents (derived from alkyl bromides) is reported. The method also furnishes, as a minor product, the symmetrical axle [2]rotaxanes resulting from the homo-coupling of the organozinc half-thread. The rotaxanes are formed in up to 56% yield with the ratio of unsymmetrical rotaxane increasing with the cavity size of the macrocycle. In the absence of the redox-active ester neither rotaxane is formed, even though the homo-coupling rotaxane product does not incorporate the redox-active ester building block. A Ni(iii) intermediate is consistent with these observations, providing support for the previously postulated mechanism of the Ni-catalyzed cross-coupling reaction.
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Affiliation(s)
- Javier Echavarren
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK .
| | - Malcolm A Y Gall
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK .
| | - Adrian Haertsch
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK .
| | - David A Leigh
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK .
| | - Vanesa Marcos
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK .
| | - Daniel J Tetlow
- School of Chemistry , University of Manchester , Oxford Road , Manchester , M13 9PL , UK .
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41
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Biagini C, Fielden SDP, Leigh DA, Schaufelberger F, Di Stefano S, Thomas D. Cover Picture: Dissipative Catalysis with a Molecular Machine (Angew. Chem. Int. Ed. 29/2019). Angew Chem Int Ed Engl 2019. [DOI: 10.1002/anie.201907113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Chiara Biagini
- School of ChemistryUniversity of Manchester Oxford Road M13 9PL Manchester UK
- Edificio Cannizzaro (VEC)Dipartimento di ChimicaUniversità degli Studi di Roma “La Sapienza” Piazzale Aldo Moro 5 00185 Roma Italy
| | | | - David A. Leigh
- School of ChemistryUniversity of Manchester Oxford Road M13 9PL Manchester UK
| | | | - Stefano Di Stefano
- Edificio Cannizzaro (VEC)Dipartimento di ChimicaUniversità degli Studi di Roma “La Sapienza” Piazzale Aldo Moro 5 00185 Roma Italy
| | - Dean Thomas
- School of ChemistryUniversity of Manchester Oxford Road M13 9PL Manchester UK
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42
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Abstract
We report on catalysis by a fuel-induced transient state of a synthetic molecular machine. A [2]rotaxane molecular shuttle containing secondary ammonium/amine and thiourea stations is converted between catalytically inactive and active states by pulses of a chemical fuel (trichloroacetic acid), which is itself decomposed by the machine and/or the presence of additional base. The ON-state of the rotaxane catalyzes the reduction of a nitrostyrene by transfer hydrogenation. By varying the amount of fuel added, the lifetime of the rotaxane ON-state can be regulated and temporal control of catalysis achieved. The system can be pulsed with chemical fuel several times in succession, with each pulse activating catalysis for a time period determined by the amount of fuel added. Dissipative catalysis by synthetic molecular machines has implications for the future design of networks that feature communication and signaling between the components.
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Affiliation(s)
- Chiara Biagini
- School of ChemistryUniversity of ManchesterOxford RoadM13 9PLManchesterUK
- Edificio Cannizzaro (VEC)Dipartimento di ChimicaUniversità degli Studi di Roma “La Sapienza”Piazzale Aldo Moro 500185RomaItaly
| | | | - David A. Leigh
- School of ChemistryUniversity of ManchesterOxford RoadM13 9PLManchesterUK
| | | | - Stefano Di Stefano
- Edificio Cannizzaro (VEC)Dipartimento di ChimicaUniversità degli Studi di Roma “La Sapienza”Piazzale Aldo Moro 500185RomaItaly
| | - Dean Thomas
- School of ChemistryUniversity of ManchesterOxford RoadM13 9PLManchesterUK
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43
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Biagini C, Fielden SDP, Leigh DA, Schaufelberger F, Di Stefano S, Thomas D. Titelbild: Dissipative Catalysis with a Molecular Machine (Angew. Chem. 29/2019). Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201907113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Chiara Biagini
- School of ChemistryUniversity of Manchester Oxford Road M13 9PL Manchester UK
- Edificio Cannizzaro (VEC)Dipartimento di ChimicaUniversità degli Studi di Roma “La Sapienza” Piazzale Aldo Moro 5 00185 Roma Italy
| | | | - David A. Leigh
- School of ChemistryUniversity of Manchester Oxford Road M13 9PL Manchester UK
| | | | - Stefano Di Stefano
- Edificio Cannizzaro (VEC)Dipartimento di ChimicaUniversità degli Studi di Roma “La Sapienza” Piazzale Aldo Moro 5 00185 Roma Italy
| | - Dean Thomas
- School of ChemistryUniversity of Manchester Oxford Road M13 9PL Manchester UK
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44
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Affiliation(s)
- Chiara Biagini
- School of ChemistryUniversity of Manchester Oxford Road M13 9PL Manchester UK
- Edificio Cannizzaro (VEC)Dipartimento di ChimicaUniversità degli Studi di Roma “La Sapienza” Piazzale Aldo Moro 5 00185 Roma Italy
| | | | - David A. Leigh
- School of ChemistryUniversity of Manchester Oxford Road M13 9PL Manchester UK
| | | | - Stefano Di Stefano
- Edificio Cannizzaro (VEC)Dipartimento di ChimicaUniversità degli Studi di Roma “La Sapienza” Piazzale Aldo Moro 5 00185 Roma Italy
| | - Dean Thomas
- School of ChemistryUniversity of Manchester Oxford Road M13 9PL Manchester UK
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45
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Abstract
![]()
We
report on the stereoselective synthesis of both molecular granny
and square knots through the use of lanthanide-complexed overhand
knots of specific handedness as three-crossing “entanglement
synthons”. The composite knots are assembled by combining two
entanglement synthons (of the same chirality for a granny knot; of
opposite handedness for a square knot) in three synthetic steps: first,
a CuAAC reaction joins together one end of each overhand knot. Ring-closing
olefin metathesis (RCM) then affords the closed-loop knot, locking
the topology. This allows the lanthanide ions necessary for stabilizing
the entangled conformation of the synthons to subsequently be removed.
The composite knots were characterized by 1H and 13C NMR spectroscopy and mass spectrometry and the chirality of the
knot stereoisomers compared by circular dichroism. The synthetic strategy
of combining building blocks of defined stereochemistry (here overhand
knots of Λ- or Δ-handed entanglement) is reminiscent of
the chiron approach of using minimalist chiral synthons in the stereoselective
synthesis of molecules with multiple asymmetric centers.
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Affiliation(s)
- David A Leigh
- School of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , U.K
| | - Lucian Pirvu
- School of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , U.K
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46
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Abstract
![]()
The binding of Zn(II) cations to
a pentafoil (51) knotted
ligand allows the synthesis of otherwise inaccessible metalated molecular
pentafoil knots via transmetalation, affording the corresponding “first-sphere”
coordination Co(II), Ni(II), and Cu(II) pentanuclear knots in good
yields (≥85%). Each of the knot complexes was characterized
by mass spectrometry, the diamagnetic (zinc) knot complex was characterized
by 1H and 13C NMR spectroscopy, and the zinc,
cobalt, and nickel pentafoil knots afforded single crystals whose
structures were determined by X-ray crystallography. Lehn-type circular
helicates generally only form with tris-bipy ligand strands and Fe(II)
(and, in some cases, Ni(II) and Zn(II)) salts, so such architectures
become accessible for other metal cations only through the use of
knotted ligands. The different metalated knots all exhibit “second-sphere”
coordination of a single chloride ion within the central cavity of
the knot through CH···Cl– hydrogen
bonding and electrostatic interactions. The chloride binding affinities
were determined in MeCN by isothermal titration calorimetry, and the
strength of binding was shown to vary over 3 orders of magnitude for
the different metal-ion–knotted-ligand second-sphere coordination
complexes.
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Affiliation(s)
- Liang Zhang
- School of Chemistry and Molecular Engineering , East China Normal University , Shanghai 200062 , China.,School of Chemistry , University of Manchester , Manchester M13 9PL , United Kingdom
| | - Alexander J Stephens
- School of Chemistry , University of Manchester , Manchester M13 9PL , United Kingdom
| | | | - Lucian Pirvu
- School of Chemistry , University of Manchester , Manchester M13 9PL , United Kingdom
| | | | - Christopher J Robinson
- SYNBIOCHEM, Manchester Institute of Biotechnology , University of Manchester , Manchester M1 7DN , United Kingdom
| | - David A Leigh
- School of Chemistry and Molecular Engineering , East China Normal University , Shanghai 200062 , China.,School of Chemistry , University of Manchester , Manchester M13 9PL , United Kingdom
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47
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Abstract
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We investigate the self-assembly
dynamics of an imine-based pentafoil
knot and related pentameric circular helicates, each derived from
a common bis(formylpyridine)bipyridyl building block, iron(II) chloride,
and either monoamines or a diamine. The mixing of circular helicates
derived from different amines led to the complete exchange of the N-alkyl residues on the periphery of the metallo-supramolecular
scaffolds over 4 days in DMSO at 60 °C. Under similar conditions,
deuterium-labeled and nonlabeled building blocks showed full dialdehyde
building block exchange over 13 days for open circular helicates but
was much slower for the analogous closed-loop pentafoil knot (>60
days). Although both knots and open circular helicates self-assemble
under thermodynamic control given sufficiently long reaction times,
this is significantly longer than the time taken to afford the maximum
product yield (2 days). Highly effective error correction occurs during
the synthesis of imine-based pentafoil molecular knots and pentameric
circular helicates despite, in practice, the systems not operating
under full thermodynamic control.
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Affiliation(s)
- Jean-François Ayme
- School of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , United Kingdom.,School of Chemistry , University of Edinburgh , The King's Buildings, West Mains Road , Edinburgh EH9 3JJ , United Kingdom
| | - Jonathon E Beves
- School of Chemistry , University of Edinburgh , The King's Buildings, West Mains Road , Edinburgh EH9 3JJ , United Kingdom
| | - Christopher J Campbell
- School of Chemistry , University of Edinburgh , The King's Buildings, West Mains Road , Edinburgh EH9 3JJ , United Kingdom
| | - David A Leigh
- School of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , United Kingdom.,School of Chemistry , University of Edinburgh , The King's Buildings, West Mains Road , Edinburgh EH9 3JJ , United Kingdom
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48
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Abstract
Three 819 knots in closed-loop strands of different lengths (∼20, 23, and 26 nm) were used to experimentally assess the consequences of knot tightness at the molecular level. Through the use of 1H NMR, diffusion-ordered spectroscopy (DOSY), circular dichroism (CD), collision-induced dissociation mass spectrometry (CID-MS) and molecular dynamics (MD) simulations on the different-sized knots, we find that the structure, dynamics, and reactivity of the molecular chains are dramatically affected by the tightness of the knotting. The tautness of entanglement causes differences in conformation, enhances the expression of topological chirality, weakens covalent bonds, inhibits decomplexation events, and changes absorption properties. Understanding the effects of tightening nanoscale knots may usefully inform the design of knotted and entangled molecular materials.
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Affiliation(s)
- Liang Zhang
- School of Chemistry and Molecular Engineering, East China Normal University, 200062 Shanghai, China
- School of Chemistry, University of Manchester, M13 9PL Manchester, United Kingdom
| | | | - Angela Acocella
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, 40126 Bologna, Italy
| | - Matteo Calvaresi
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, 40126 Bologna, Italy
| | - Francesco Zerbetto
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, 40126 Bologna, Italy
| | - David A Leigh
- School of Chemistry and Molecular Engineering, East China Normal University, 200062 Shanghai, China;
- School of Chemistry, University of Manchester, M13 9PL Manchester, United Kingdom
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49
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Danon JJ, Leigh DA, Pisano S, Valero A, Vitorica‐Yrezabal IJ. A Six-Crossing Doubly Interlocked [2]Catenane with Twisted Rings, and a Molecular Granny Knot. Angew Chem Int Ed Engl 2018; 57:13833-13837. [PMID: 30152565 PMCID: PMC6221036 DOI: 10.1002/anie.201807135] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/13/2018] [Indexed: 11/17/2022]
Abstract
A molecular 6 2 3 link (a six crossing, doubly interlocked, [2]catenane with twisted rings) and a 31 #31 granny knot (a composite knot made up of two trefoil tangles of the same handedness) were constructed by ring-closing olefin metathesis of an iron(II)-coordinated 2×2 interwoven grid. The connections were directed by pendant phenyl groups to be between proximal ligand ends on the same faces of the grid. The 6 2 3 link was separated from the topoisomeric granny knot by recycling size-exclusion chromatography. The identity of each topoisomer was determined by tandem mass spectrometry and the structure of the 6 2 3 link confirmed by X-ray crystallography, which revealed two 82-membered macrocycles, each in figure-of-eight conformations, linked through both pairs of loops.
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Affiliation(s)
- Jonathan J. Danon
- School of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
| | - David A. Leigh
- School of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
| | - Simone Pisano
- School of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
| | - Alberto Valero
- School of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
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50
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Luger P, Dittrich B, Mebs S, Slawin AM, Leigh DA. Analysis of two [2]catenanes based on electron densities from invariom refinement and results from DFT calculations. Zeitschrift für Naturforschung B 2018. [DOI: 10.1515/znb-2018-0179] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Abstract
Catenanes are of considerable interest as potential building blocks for molecular machines. The simplest [2]catenanes, Hopf links, consist of two macrocycles that are mechanically interlocked. This unusual architecture cannot be opened without breaking at least one covalent bond. Based on these structural characteristics, unusual properties on Hirshfeld or electrostatic potential surfaces could be expected. For a comparison of their structural and electronic properties, the electron densities (EDs) of two [2]catenanes, coded H22 and H4L7 in the original papers, were examined after application of the invariom formalism, relying on X-ray diffraction data collected earlier. The obtained electron density distributions were subjected to an analysis using the QTAIM formalism to yield bond and atomic properties. Moreover, molecular Hirshfeld surfaces and electrostatic potentials (ESP) were calculated. There are different types of intra- and intermolecular interactions in these two [2]catenanes. In addition to classical N–H···N and C–H···O hydrogen bonds, various types of π···π interactions in H22 and in H4L7 exist. Most of them are verified by local ED concentrations visible on the corresponding Hirshfeld surfaces, except for the parallel π···π interactions in H22, which are either too weak or too diffuse to generate an ED signal on the Hirshfeld surface between the contributing aromatic rings. The electrostatic potentials (ESPs) were calculated and displayed on molecular surfaces. The interaction in the cavity of one macrocycle with the penetrated fragment of the second one was examined and it was found that corresponding to the above-mentioned contacts attractive and repulsive interactions exist. Additionally the ED was examined using results of density functional calculations, including non-covalent interaction index (NCI) and electron localizability indicator (ELI-D) surface analysis, complementing experimental findings.
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Affiliation(s)
- Peter Luger
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin , Fabeckstraße 36a , Berlin D-14195 , Germany
| | - Birger Dittrich
- Institut für Anorganische Chemie und Strukturchemie, Heinrich-Heine-Universität Düsseldorf , Universitätsstraße 1 , Düsseldorf D-40225 , Germany
| | - Stefan Mebs
- Institut für Experimentalphysik, Freie Universität Berlin , Arnimalle 14 , Berlin D-14195 , Germany
| | - Alexandra M.Z. Slawin
- School of Chemistry , University of St. Andrews, Purdie Building , St. Andrews, Fife KY16 9ST , UK
| | - David A. Leigh
- School of Chemistry , The University of Manchester, Oxford Road , Manchester M13 9PL , UK
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