Molecular Machines. Fraser Stoddart

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1 Molecular Machines Fraser Stoddart A molecular machine is a multicomponent system in which the reversible movement of the components can be controlled by an external stimulus. Known examples of molecular machines includes nondegenerate rotaxanes, nondegenerate catenanes, as well as pseudorotaxanes. Control of the motions of the components in those systems has been introduced, which results in a change in properties which produce a signal that allows the operation of the machine to be monitored. The outside stimuli can be photons, electrons, or chemical species, to

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3 PSEUDOROTAXANE ROTAXANE CATENANE

4 HOW SMALL MOLECULAR MACHINES REALLY ARE?

5 HOW SMALL MOLECULAR MACHINES REALLY ARE?

6 HOW SMALL MOLECULAR MACHINES REALLY ARE?

7 HOW SMALL MOLECULAR MACHINES REALLY ARE? Molecules

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9 ATPase is the most Important ROTAXANE in Nature Rastogi & Girvin, Nature, 1999

10 Noji et al., Nature, 1997 Futai et al.,science,1999

11 The function of Kinesin Kawaguchi and Ishiwata Science, 2001

12 The movement mechanisms of Kinesin Hua, Chung and Gelles, Science 2002 Examples of two alternative classes of mechanisms for processive, high-duty ratio movement by kinesin. Kinesin hydrolyzes one molecule of ATP and moves 8 nm along a microtubule protofilament in a single catalytic cycle.

13 ROTAXANE BASED MOLECULAR MOTORS (SHUTTLE)

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15 Signal 1

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19 Signal 2

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24 Bissel, Cordova, Kaifer, Stoddart, Science, 1994

25 Jean-Pierre Sauvage

26 CATENANE BASED MOLECULAR MOTORS

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28 pp Fraser Stoddart

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30 Signal 1

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34 Signal 2

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38 IN ORDER TO REACH MACHINE LIKE BEHAVIOR COMPLEX STRUCTURES WITH MULTIPLE FUNCTIONS MUST BE DESIGNED AND SYNTHETIZED A catenane designed to perform as an electrochemically powered molecular-level rotary motor.

39 (A) Molecular drawing of the bistable [2]catenane used in this work. The voltage-driven circumrotation of co-conformer [A 0 ] to co-conformer [B + ] is the basis of the device.

40 (B) Proposed mechanism for the operation of the device. Co-conformer [A 0 ] represents both the ground-state structure of the [2]catenane and the switch open state of the device. When the [2]catenane is oxidized, the TTF groups (green) are ionized. The coconformer [B + ] is formed. When the voltage is reduced to a near-zero bias, the coconformer [B 0 ] is formed, and this represents the switch closed state of the device. Partial reduction of the cyclophane (+2 V) is necessary to regenerate the [A 0 ] co-conformer. The reduced co-conformer [AB#] is indicated with an unknown oxidation state.

41 Molecular movement induced by Cu(II)/Cu(I) atoms A. Livoreil, C. O. Dietrich-Buchecker, J.-P. Sauvage, J. Am. Chem. Soc. 1994

42 ROTAXANE BASED MOLECULAR MUSCLES

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44 M.-C. JIMENEZ-MOLERO, C. DIETRICH-BUCHECKER, J.-P. SAUVAGE Chem. Comm.,(2003).

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47 Science, Vol. 294, 21 December 2001, p.2442

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49 SUMMARY

50 SUMMARY IT IS EASY TO DESING AND PREPARE (WITH MANY STEPS) FUNTIONAL MOLECULES AND MOLECULAR MACHINES

51 SUMMARY IT IS EASY TO DESING AND PREPARE (WITH MANY STEPS) FUNTIONAL MOLECULES AND MOLECULAR MACHINES THE MOST DIFFICULT AND DEMANDING TASK IS TO COUPLE THE FUNCTIONAL MOLECULES AND MOLECULAR MACHINES TO MACRO WORLD

52 SUMMARY IT IS EASY TO DESING AND PREPARE (WITH MANY STEPS) FUNTIONAL MOLECULES AND MOLECULAR MACHINES THE MOST DIFFICULT AND DEMANDING TASK IS TO COUPLE THE FUNCTIONAL MOLECULES AND MOLECULAR MACHINES TO MACRO WORLD REAL MOLECULAR MACHINES ARE AT PRESENT SCIENCE FICTION, BUT FUNCTIONAL MOLECULES WITH MACHINE-LIKE FUNCTION DO EXIST ALREADY TODAY

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54 The Inauguration of Jyväskylä Nanoscience Center

55 The Inauguration of Jyväskylä Nanoscience Center Fraser Stoddart

56 The Inauguration of Jyväskylä Nanoscience Center Fraser Stoddart Olli Ikkala

57 The Inauguration of Jyväskylä Nanoscience Center David Reinhoudt Fraser Stoddart Olli Ikkala

58 The Inauguration of Jyväskylä Nanoscience Center David Reinhoudt Fraser Stoddart Demonstration Olli Ikkala of a Molecular Machine