DOCSLIB.ORG

Rise of the Molecular Machines Euan R

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Rise of the Molecular Machines Euan R Angewandte. Essays International Edition:DOI:10.1002/anie.201503375 SupramolecularSystems German Edition:DOI:10.1002/ange.201503375 Rise of the Molecular Machines Euan R. Kay* and David A. Leigh* molecular devices ·molecular machines · molecular motors ·molecular nanotechnology Introduction inspirational in general terms,itisdoubtful whether either of these manifestos had much practical influence on the devel- “When we get to the very,very small world …wehave alot of opment of artificial molecular machines.[5] Feynmans talk new things that would happen that represent completely new came at atime before chemists had the synthetic methods and opportunities for design …Atthe atomic level we have new kinds analytical tools available to be able to consider how to make of forces and new kinds of possibilities, new kinds of effects. The molecular machines;Drexlers somewhat nonchemical view problem of manufacture and reproduction of materials will be of atomic construction is not shared by the majority of quite different …inspired by biological phenomena in which experimentalists working in this area. In fact, “mechanical” chemical forces are used in arepetitious fashion to produce all movement within molecules has been part of chemistry since kinds of weird effects (one of which is the author) …” conformational analysis became established in the 1950s.[6] As Richard P. Feynman (1959)[2] well as being central to advancing the structural analysis of complex molecules,this was instrumental in chemists begin- It has long been appreciated that molecular motors and ning to consider dynamics as an intrinsic aspect of molecular machines are central to almost every biological process.The structure and hence aproperty they could aspire to control. harvesting of energy from the sun, the storing of energy, Artificial systems were designed to exhibit particular con- transporting cargoes around the cell, the movement of cells, formational behavior, such as the “cog-wheeling”-correlated generation of force (at both the molecular and macroscopic motions of aromatic “blades” in triptycenes and related levels), replication, transcription, translation, synthesis,driv- structures constructed by the groups of O¯ ki, Mislow,and ing chemical systems away from equilibrium, etc.—virtually Iwamura in the 1970s and 1980s (e.g. 1,Figure 1a).[7] Before every biological task involves molecular machines.[1] Given long,stimuli-induced changes in conformation had been used the success of mankinds machines in the macroscopic world, to control molecular recognition properties;two of the from the Stone-Age wheel to the modern-day smart phone,it seminal examples being Rebeks use of allostery[8] (binding was inevitable that we should one day seek to achieve the at one site influencing binding affinity at asecond site; 2, ultimate in machine miniaturization. However,ithas taken Figure 1b)and Shinkais azobenzene photoswitch[9] for some time to gain sufficient mastery over the necessary modulating the cation-binding properties of crown ethers (3, synthetic and supramolecular chemistry (and related physics) Figure 1c). However,the field of synthetic molecular ma- for this field to begin to flourish. chines really began to take off with developments that Richard Feynmans classic 1959 lecture Theres plenty of occurred in the early 1990s. room at the bottom[2] outlined some of the promise that man- made molecular machines might hold, ascientific “taster” that Eric Drexler embraced for his controversial[3] vision of Architectures for Well-Defined Large-Amplitude “nanobots” and “molecular assemblers”.[4] However,whilst Molecular-Level Motions In many ways the field of artificial molecular machinery [*] Dr.E.R.Kay EaStCHEM School of Chemistry,University of St Andrews began with J. Fraser Stoddarts invention of a“molecular [10] North Haugh, St Andrews KY16 9ST (UK) shuttle” (4)in1991 (Figure 2). In this rotaxane (a molecule E-mail:[email protected] with aring mechanically locked onto an axle by bulky Homepage: http://kaylab.wp.st-andrews.ac.uk stoppers), the ring (shown in blue) moves between two Prof. D. A. Leigh preferred binding sites (the two hydroquinone units,shown in School of Chemistry,University of Manchester red) by random thermal motion (Brownian motion). Theuse Oxford Road, Manchester M13 9PL (UK) of template effects to assemble mechanically linked mole- E-mail:[email protected] cules (catenanes and, later,rotaxanes) had been introduced Homepage: http://www.catenane.net by Jean-Pierre Sauvage in the early 1980s;[11] Stoddarts great 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. insight was to recognize that the threaded (mechanically KGaA. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distributionand interlocked) architecture of arotaxane could allow for the reproduction in any medium, provided the original work is properly large-amplitude motion of molecular-level components in cited. awell-defined and potentially controllable manner. The 10080 2015 The Authors. Published by Wiley-VCH Verlag GmbH &Co. KGaA, Weinheim Angew.Chem.Int. Ed. 2015, 54,10080 –10088 Angewandte Chemie authors of the 1991 JACS paper noted:“Insofar as it becomes possible to control the movement of one molecular compo- nent with respect to the other in a[2]rotaxane,the technology for building molecular machines will emerge.”[10] This statement turned out to be highly prescient and the paper hugely influential. Although mechanically interlocked structures are not necessary to construct molecular machines (see below), they provided the first practical synthetic molecular architecture through which well-defined large- amplitude molecular-level motions could be selectively ad- dressed, studied, and utilized.[1b–g] This gave an exciting and compelling reason to make rotaxanes and catenanes,and the area burgeoned from these molecules being academic curi- osities in the 1960s (when catenanes and rotaxanes were first made by long and/or inefficient synthetic routes[12])through to 1989 (when Stoddart and co-workers made their first cate- nane,[13] six years after Sauvage and co-workers revolution- ized the strategy for their synthesis through the use of template methods[11])tothe mainstream area it is now,[14] with hundreds of groups active in this field from the mid-1990s onwards. Switching the Relative Positions of Molecular Components—From Molecules to Machines By desymmetrizing arotaxane thread to have two differ- ent potential binding sites,or“stations”, whose relative affinity for the ring could be switched, Stoddart, Kaifer, and co-workers arguably invented the first artificial molecular Brownian motion machine (5,Figure 3).[15] Thecationic ring Figure 1. Correlated intramolecular motions within “proto-molecular (shown in dark blue) prefers to reside over the benzidine machines”: a) Intramolecular mechanicalcog-wheeling(this example, Iwamura et al.;1983);[7] b) anegative heterotopicallosteric receptor (Rebek et al.;1979);[8] c) photoswitchable binding of acrown ether (Shinkai et al.;1980).[9] Euan Kay received his MChem from the University of Edinburgh in 2002 and his PhD in 2006 under the supervision of David Leigh. He was the recipient of a2007 IUPAC Prize for Young Chemists. Following group (shown in light blue) rather than the biphenol site postdoctoral work in Edinburgh, he joined (shown in orange). However,protonation (or electrochemical Prof. Moungi Bawendi at MIT (2008– oxidation) of the benzidine station (now in purple) renders 2010). Since 2011, he has been aRoyal the biphenol group the preferred binding site for the cationic Society of Edinburgh/Scottish Government ring, thereby causing anet displacement of the ring along the Personal Research Fellow at the University track. This system marks the first example of alarge- of St Andrews. His research interests focus on translating dynamic and stimuli-respon- amplitude,well-defined, controlled switching of the position sive (supra)molecular systems into the of acomponent along amolecular track. nanoworld. Thegroups of Stoddart and others (notably those of David Leigh was born in Birmingham and Sauvage,Balzani, Fujita, Hunter,Vçgtle,Sanders,Beer, and obtained his BSc and PhD from the Uni- Leigh) contributed to the development of many other versity of Sheffield. After postdoctoral re- rotaxane- and catenane-forming motifs and strategies over search in Ottawa (1987–1989), he was the period 1992–2007,[1b,f,g] and invented many different ways appointed to aLectureship at the University of switching the positions of the components in rotaxane and of ManchesterInstitute of Science and Technology.After spells at the Universitiesof catenane architectures with various stimuli (light, electro- Warwick and Edinburgh he returned to chemistry,pHvalue,polarity of the environment, cation Manchesterin2012, where he currently binding,anion binding,allosteric effects,temperature,rever- holds the Sir Samuel Hall Chair of sible covalent-bond formation, etc).[1b,f,g] Thenext key ad- Chemistry.Hewas elected aFellow of the vance needed was—and in some respects still is—to find ways Royal Society in 2009. His research interests to use the change of the position of the components of include chemical topology and synthetic amolecular machine to perform useful tasks (see below). molecular-level motors and machines. Angew.Chem. Int.Ed. 2015, 54,10080 –100882015 The Authors. Published by Wiley-VCH Verlag GmbH &Co. KGaA, Weinheim www.angewandte.org 10081 Angewandte. Essays
Load more

Recommended publications
  • National Academy Elects IMS Fellows Have You Voted Yet?
    Volume 38 • Issue 5 IMS Bulletin June 2009 National Academy elects IMS Fellows CONTENTS The United States National Academy of Sciences has elected 72 new members and 1 National Academy elects 18 foreign associates from 15 countries in recognition of their distinguished and Raftery, Wong continuing achievements in original research. Among those elected are two IMS Adrian Raftery 2 Members’ News: Jianqing Fellows: , Blumstein-Jordan Professor of Statistics and Sociology, Center Fan; SIAM Fellows for Statistics and the Social Sciences, University of Washington, Seattle, and Wing Hung Wong, Professor 3 Laha Award recipients of Statistics and Professor of Health Research and Policy, 4 COPSS Fisher Lecturer: Department of Statistics, Stanford University, California. Noel Cressie The election was held April 28, during the business 5 Members’ Discoveries: session of the 146th annual meeting of the Academy. Nicolai Meinshausen Those elected bring the total number of active members 6 Medallion Lecture: Tony Cai to 2,150. Foreign associates are non-voting members of the Academy, with citizenship outside the United States. Meeting report: SSP Above: Adrian Raftery 7 This year’s election brings the total number of foreign 8 New IMS Fellows Below: Wing H. Wong associates to 404. The National Academy of Sciences is a private 10 Obituaries: Keith Worsley; I.J. Good organization of scientists and engineers dedicated to the furtherance of science and its use for general welfare. 12-3 JSM program highlights; It was established in 1863 by a congressional act of IMS sessions at JSM incorporation signed by Abraham Lincoln that calls on 14-5 JSM tours; More things to the Academy to act as an official adviser to the federal do in DC government, upon request, in any matter of science or 16 Accepting rejections technology.
    [Show full text]
  • Rise of the Molecular Machines Euan R
    Angewandte. Essays International Edition: DOI: 10.1002/anie.201503375 Supramolecular Systems German Edition: DOI: 10.1002/ange.201503375 Rise of the Molecular Machines Euan R. Kay* and David A. Leigh* molecular devices · molecular machines · molecular motors · molecular nanotechnology Introduction inspirational in general terms, it is doubtful whether either of these manifestos had much practical influence on the devel- “When we get to the very, very small world … we have a lot of opment of artificial molecular machines.[5] Feynmans talk new things that would happen that represent completely new came at a time before chemists had the synthetic methods and opportunities for design … At the atomic level we have new kinds analytical tools available to be able to consider how to make of forces and new kinds of possibilities, new kinds of effects. The molecular machines; Drexlers somewhat nonchemical view problem of manufacture and reproduction of materials will be of atomic construction is not shared by the majority of quite different … inspired by biological phenomena in which experimentalists working in this area. In fact, “mechanical” chemical forces are used in a repetitious fashion to produce all movement within molecules has been part of chemistry since kinds of weird effects (one of which is the author) …” conformational analysis became established in the 1950s.[6] As Richard P. Feynman (1959)[2] well as being central to advancing the structural analysis of complex molecules, this was instrumental in chemists begin- It has long been appreciated that molecular motors and ning to consider dynamics as an intrinsic aspect of molecular machines are central to almost every biological process.
    [Show full text]
  • Probing the Dynamics of the Imine-Based Pentafoil Knot and Pentameric Circular Helicate Assembly † ‡ ‡ § ‡ † ‡ Jean-Francoiş Ayme, , Jonathon E
    This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited. Article Cite This: J. Am. Chem. Soc. 2019, 141, 3605−3612 pubs.acs.org/JACS Probing the Dynamics of the Imine-Based Pentafoil Knot and Pentameric Circular Helicate Assembly † ‡ ‡ § ‡ † ‡ Jean-Francoiş Ayme, , Jonathon E. Beves, , Christopher J. Campbell, and 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 *S Supporting Information ABSTRACT: 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.
    [Show full text]
  • Weak Functional Group Interactions Revealed Through Metal-Free Active Template Rotaxane Synthesis
    ARTICLE https://doi.org/10.1038/s41467-020-14576-7 OPEN Weak functional group interactions revealed through metal-free active template rotaxane synthesis Chong Tian 1,2, Stephen D.P. Fielden 1,2, George F.S. Whitehead 1, Iñigo J. Vitorica-Yrezabal1 & David A. Leigh 1* 1234567890():,; 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. 1 Department of Chemistry, University of Manchester, Manchester M13 9PL, UK. 2These authors contributed equally: Chong Tian, Stephen D. P. Fielden. *email: [email protected] NATURE COMMUNICATIONS | (2020) 11:744 | https://doi.org/10.1038/s41467-020-14576-7 | www.nature.com/naturecommunications 1 ARTICLE NATURE COMMUNICATIONS | https://doi.org/10.1038/s41467-020-14576-7 he bulky axle end-groups of rotaxanes mechanically lock To explore the scope of this unexpected method of rotaxane Trings onto threads, preventing the dissociation of the synthesis, here we carry out a study of the reaction with a series of components even if the interactions between them are not related electrophiles.
    [Show full text]
  • Volume 70, No. 3, October 2006
    Inside Volume 70, No.3, October 2006 Articles and Features 70 Structure Determination of New Algal Toxins using NMR Methods Alistair L. Wilkins*,a and Christopher O. Milesb,c 74 Faecal Sterols and Fluorescent Whiteners as Indicators of the Source of Faecal Contamination Megan Devane,* Darren Saunders and Brent Gilpin 78 The Curious Case of Phosphate Solubility Andrew J. Pratt 82 Water Oxidation by Ruthenium Dimers Matthew I. J. Polson 85 Fluorinated Analogues of Biological Molecules: Accessing New Chemical, Physical and Biological Properties Michael Edmondsa and Victoria Peddieb 88 Drug Discovery in the New Millennium Steven G. Aitken 93 2006 NZIC Salary Survey Summary 98 Chemical Processes In New Zealand – Where To From Here? 101 38th International Chemistry Olympiad Regular Columns 99 Patent Proze 102 NZIC News 108 Conference Calendar Advertisers Index Cover Shimadzu Scientific Instruments Ltd Back Cover Shimadzu Scientific Instruments Ltd Inside Front Cover Global Science Inside Back Cover Pacific Laboratory Products 81 NZIC Conference 84 Graham B Jackson: Certified Reference Materials Disclaimer The New Zealand Institute of Scientific Editor The views and opinions expressed in Chemistry Incorporated Professor B. Halton, FRSNZ, Hon, FNZIC Chemistry in New Zealand are those of the PO Box 39-112 School of Chemical and Physical Sciences individual authors and are not necessarily those Harewood, Christchurch Victoria University of the publisher, the Editorial Board or the PO Box 600 Phone: +64 3 359 7275 New Zealand Institute of Chemistry. Whilst Wellington, New Zealand Fax: +64 3 359 7248 the publisher has taken every precaution to Email: NZIC.Offi[email protected] Phone: +64 4 463 5954 ensure the total accuracy of material contained Fax: +64 4 463 5241 in Chemistry in New Zealand, no responsibility Managing Editors and Publishers Email: [email protected] for errors or omissions will be accepted.
    [Show full text]
  • Top-25 Publications
    David Leigh (University of Manchester, UK) – 25 most significant publications (reverse chronological order) 1. "A catalysis-driven artificial molecular pump", S. Amano, S. D. P. Fielden and D. A. Leigh, Nature 594, 529-534 (2021). 2. "A molecular endless (74) knot", D. A. Leigh, J. J. Danon, S. D. P. Fielden, J.-F. Lemonnier, G. F. S. Whitehead and S. L. Woltering, Nat. Chem. 13, 117-122 (2021). 3. "Self-assembly of a layered 2D molecularly woven fabric", D. P. August, R. A. W. Dryfe, S. J. Haigh, P. R. C. Kent, D. A. Leigh, J.-F. Lemonnier, Z. Li, C. A. Muryn, L. I. Palmer, Y. Song, G. F. S. Whitehead and R. J. Young, Nature 588, 429-435 (2020). 4. "Tying different knots in a molecular strand", D. A. Leigh, F. Schaufelberger, L. Pirvu, J. Halldin Stenlid, D. P. August and J. Segard, Nature 584, 562-568 (2020). 5. "Rotary and linear molecular motors driven by pulses of a chemical fuel", S. Erbas-Cakmak, S. D. P. Fielden, U. Karaca, D. A. Leigh, C. T. McTernan, D. J. Tetlow and M. R. Wilson, Science 358, 340-343 (2017). Cited 154 times as of 23.6.21 (GooSch). 6. "Stereodivergent synthesis with a programmable molecular machine", S. Kassem, A. T. L. Lee, D. A. Leigh, V. Marcos, L. I. Palmer and S. Pisano, Nature 549, 374-378 (2017). Cited 113 times as of 23.6.21 (GooSch). 7. "Braiding a molecular knot with eight crossings", J. J. Danon, A. Krüger, D. A. Leigh, J.-F. Lemonnier, A. J. Stephens, I.
    [Show full text]
  • Rotaxanes and Catenanes by Click Chemistry
    Mini Review Rotaxanes and Catenanes by Click Chemistry Ognjen Sˇ. Miljanic´a, William R. Dichtela, b, Ivan Aprahamiana, Rosemary D. Rohdeb, Heather D. Agnewb, James R. Heathb* and J. Fraser Stoddarta* a California NanoSystems Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, 405 Hilgard Avenue, Los Angeles, California 90095, USA, E-mail: [email protected] b Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA, E-mail: [email protected] Keywords: Catenanes, Click chemistry, Interlocked molecules, Rotaxanes, Self-assembly, Surface chemistry Received: June 1, 2007; Accepted: July 11, 2007 DOI: 10.1002/qsar.200740070 Abstract Copper(I)-catalyzed Huisgen 1,3-dipolar cycloaddition between terminal alkynes and azides – also known as the copper (Cu)-catalyzed Azide-Alkyne Cycloaddition (CuAAC) – has been used in the syntheses of molecular compounds with diverse structures and functions, owing to its functional group tolerance, facile execution, and mild reaction conditions under which it can be promoted. Recently, rotaxanes of four different structural types, as well as donor/acceptor catenanes, have been prepared using CuAAC, attesting to its tolerance to supramolecular interactions as well. In one instance of a rotaxane synthesis, the catalytic role of copper has been combined successfully with its previously documented ability to preorganize rotaxane precursors, i.e., form pseudoro- taxanes. The crystal structure of a donor/acceptor catenane formed using the CuAAC reaction indicates that any secondary [p···p] interactions between the 1,2,3-triazole ring and the bipyridinium p-acceptor are certainly not destabilizing. Finally, the preparation of robust rotaxane and catenane molecular monolayers onto metal and semiconductor surfaces is premeditated based upon recent advances in the use of the Huisgen reaction for surface functionalization.
    [Show full text]
  • The Magic of Chemistry David Leigh Has a Love of Chemistry...And Magic
    Chemical Science Interview The magic of chemistry David Leigh has a love of chemistry...and magic. Alison Stoddart finds out more Who inspired you to become a scientist? You like to practice magic. What is the most magical My high school chemistry teacher Dave Clarke. I thing about chemistry to you? think that’s a common thing amongst chemists. Chemistry allows you create things that never He made chemistry seem fun and exciting. There were and to change the world and change society, were several others from my class who went on and that’s an amazing thing. James Clerk Maxwell, to do chemistry. Barry Moore, on the chemistry the 19th century Scottish physicist, came up with faculty at Strathclyde, also went to my high school. the theory that light was really electromagnetic radiation. A feat of which Richard Feynman said, What motivated you to study molecular machines? ‘…ten thousand years from now - there can be little I worked in Fraser Stoddart’s group before he doubt that the most significant event of the 19th made any catenanes or rotaxanes. We made our century will be judged as Maxwell’s discovery of first catenane about five years after Fraser did. I the laws of electrodynamics.’ I think there are still could see that there was nothing interesting about those kinds of things to be discovered and there is a catenane or a rotaxane in itself. The interesting still that impact to be had on society. thing about them is the possibility to control a well-defined, large-amplitude motion. That’s How long have you been a magician? what you need to make a molecular machine.
    [Show full text]
  • The Metastability of an Electrochemically Controlled
    [28]W. L. Jorgensen, J. Tirado-Rives, J. Am. Chem. Soc. 1988, 110, 1657. guise of bistable [2]rotaxanes in which the ring component can [29]Gaussian 98 (Revision A.11.3), M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. be induced[5] to move relative to the dumbbell-shaped one by Scuseria, M. A. Robb, J. R. Cheeseman, V. G. Zakrzewski, J. A. Montgomery, R. E. Stratmann, J. C. Burant, S. Dapprich, J. M. Millam, A. D. Daniels, K. N. altering the redox characteristics of the molecules. Such Kudin, M. C. Strain, O. Farkas, J. Tomasi, V. Barone, M. Cossi, R. Cammi, B. precisely controllable nanoscale molecular machines and Mennucci, C. Pomelli, C. Adamo, S. Clifford, J. Ochterski, G. A. Petersson, switches have attracted a lot of attention[2, 3] because of their P. Y. Ayala, Q. Cui, K. Morokuma, D. K. Malick, A. D. Rabuck, K. Raghava- potential to meet the expectations of a visionary[6] and to act as chari, J. B. Foresman, J. Cioslowski, J. V. Ortiz, B. B. Stefanov, G. Liu, A. Liashenko, P. Piskorz, I. Komaromi, R. Gomperts, R. L. Martin, D. J. Fox, T. some of the smallest components for the engineering of Keith, M. A. Al-Laham, C. Y. Peng, A. Nanayakkara, C. Gonzalez, M. nanoelectromechanical systems (NEMs) and the fabrication of Challacombe, P. M. W. Gill, B. G. Johnson, W. Chen, M. W. Wong, J. L. nanoelectronic devices.[7] Andres, M. Head-Gordon, E. S. Replogle, J. A. Pople, Gaussian, Inc., Although the redox-switching properties of numerous bista- Pittsburgh, PA, 2002.
    [Show full text]
  • Making Molecular Machines
    CONVERSATIONS WITH SCIENTISTS David A. Leigh: Making Molecular Machines "In the field of molecular machines I think the most important development of the last 20 years is the understanding of how to get directional motion from random Brownian motion. It is the key to making molecular motors and, ultimately, all sophisticated molecular machines." University of Manchester David A. Leigh is a Royal Society Research Professor and, since 2014, the Sir Samuel Hall Chair of Chemistry at the University of Manchester in the United Kingdom. Born in 1963 in Birmingham, England, Leigh earned a bachelor's degree in chemistry from the UK's University of Sheffield in 1984 and received a Ph.D from the same institution in 1987. For the next two years, Leigh worked as a postdoctoral research associate at the National Research Council of Canada in Ottawa. He returned to Britain in 1989 to lecture in organic chemistry at the University of Manchester Institute of Science and Technology. In 1998, Leigh moved on to a chair in synthetic chemistry at the University of Warwick and, in 2001 accepted a chair in organic chemistry at the University of Edinburgh. In 2012, Leigh joined the University of Manchester faculty. Leigh is the recipient of numerous honors and awards. He has received research fellowships from the Engineering and Physical Science Research Council and from the European Research Council. His awards include the Feynman Prize for Nanotechnology, the Descartes Prize for Research, and several awards from the Royal Society of Chemistry. He is a fellow of such prestigious associations as the Royal Society of London and the Academia Europaea.
    [Show full text]
  • Molecular Nanoelectronics
    Proceedings of the IEEE, 2010 1 Molecular Nanoelectronics Dominique Vuillaume photo-, electro-, iono-, magneto-, thermo-, mechanico or Abstract—Molecular electronics is envisioned as a promising chemio-active effects at the scale of structurally and candidate for the nanoelectronics of the future. More than a functionally organized molecular architectures" (adapted from possible answer to ultimate miniaturization problem in [3]). In the following, we will review recent results about nanoelectronics, molecular electronics is foreseen as a possible nano-scale devices based on organic molecules with size way to assemble a large numbers of nanoscale objects (molecules, nanoparticules, nanotubes and nanowires) to form new devices ranging from a single molecule to a monolayer. However, and circuit architectures. It is also an interesting approach to problems and limitations remains whose are also discussed. significantly reduce the fabrication costs, as well as the The structure of the paper is as follows. Section II briefly energetical costs of computation, compared to usual describes the chemical approaches used to manufacture semiconductor technologies. Moreover, molecular electronics is a molecular devices. Section III discusses technological tools field with a large spectrum of investigations: from quantum used to electrically contact the molecule from the level of a objects for testing new paradigms, to hybrid molecular-silicon CMOS devices. However, problems remain to be solved (e.g. a single molecule to a monolayer. Serious challenges for better control of the molecule-electrode interfaces, improvements molecular devices remain due to the extreme sensitivity of the of the reproducibility and reliability, etc…). device characteristics to parameters such as the molecule/electrode contacts, the strong molecule length Index Terms—molecular electronics, monolayer, organic attenuation of the electron transport, for instance.
    [Show full text]
  • Supramolecular Chemistry of Nanomaterials
    Supramolecular Chemistry of Nanomaterials Joachim Steinke Ramon Vilar Lecture 6 – Towards the Development of Molecular Machines Department of Chemistry Imperial College of Science, Technology and Medicine [email protected] [email protected] Lecture 6 - Outline •Concepts and introduction •Natural molecular machines •ATP synthase •Supramolecular springs •Developing synthetic molecular machines •Molecular muscle •Molecular wires •Insulated molecular wires •Current problems for the development of molecular machines Definitions Machine: Any system, usually of rigid bodies formed and connected to alter, transmit, and direct applied forces in a predetermined manner to accomplish a specific objective such as the performance of useful work. Motor: Device that converts any form of energy into mechanical energy. Molecular motors convert chemical energy into mechanical force and movement. As for their macroscopic counterparts, molecular machines are characterised by: (i) the kind of energy input supplied to make them work (ii) the kind of movement performed by their components (iii) the way in which their operation can be controlled (iv) the possibility to repeat the operation at will (v) the time scale needed to complete a cycle of operation (vi) the function performed Although molecular machines are widespread in Nature, the development of synthetic molecular machines is still in the very early stages. To date, several components of such potential machines have been produced, but there is still a lack of actual molecular machines. Some of such components are schematically shown in this slide: From previous lecture: Molecular level plug Molecular Switch (Logic Gate) Balzani et al. Acc. Chem. Res., 34 (6), 445 -455, 2001 Photocontrollable Abacus V.
    [Show full text]