Transcript Brazil: SAXS and High Pressure

Rotaxanes and Catenanes as
Prototypes of
Molecular Machines and Motors
Christiane Dietrich-Buchecker, Maria Consuelo Jimenez-Molero,
Valerie Sartor, and Jean-Pierre Sauvage
Laboratoire de Chimie Organo-Minerale, Faculté de Chimie, Université
Louis Pasteur, Strasbourg Cedex, France
Pure Appl. Chem., Vol. 75, No. 10, pp. 1383–1393, 2003.
Derek Dorman
Macromolecular Studies
December 3, 2004
Outline
I.
Nanotechnology (Introduction)
a.
b.
c.
II.
Why NanoTech?
Founding Fathers?
The idea.
The Article
a.
b.
Part I: Cu(l)-Templated synthesis of Catenanes.
Part II: Rotaxanes as molecular machines.
III. Conclusions
Introduction
• Nanotechnology
– Chemistry is nanoscale!
– The development and practical applications of
structures and devices on a nanometer scale
(between 1 and 100 nanometers).
– Nanoscience is the scientific study of the
properties of the nanometric world.
Feynman the Visionary
"There's Plenty of Room at the Bottom,
An Invitation to Enter a New Field of
Physics"
(presented on December 29th 1959 at the annual meeting of the
American Physical Society at the California Institute of Technology):
"The principles of physics, as far as I can see, do not
speak against the possibility of maneuvering things
atom by atom. It is not an attempt to violate any laws;
it is something, in principle, that can be done; but in
practice, it has not been done because we are too
big.1"
Feynman Challenge
1 The first prize was to reduce the words on a page by 25,000 times so that
it could be read by and electron microscope.
2 “And I want to offer another prize …$1,000 to the first guy who makes an
operating electric motor -- a rotating electric motor which can be controlled
from the outside and, not counting the lead-in wires, that is only 1/64 inch
cube.“
1/64th inch = 0.4 mm = 400 m = 400,000 nm
K. Eric Drexler
• Engines of Creation: The Coming Era of
Nanotechnology6
– Nanobots: Machines that could stack atoms.
• Foresight Institute
AKA Nanoists
– “Foresight Institute's goal is to guide emerging
technologies to improve the human condition.
Foresight focuses its efforts upon nanotechnology, the
coming ability to build products—of any size—with
atomic precision.2”
Molecular Machines
• In Nanosystems by K.
Eric Drexler, many
molecular devices are
proposed such as this
Neon pump7.
The Nano Toolbox
• Top-Down (Miniaturization)
– Lithography
– Nano-machining
– Nano-manipulation
• Bottom-Up (Self-assembly/Synthesis)
– Self-assembly
– Nucleation and growth
– Templating
Nanotechnology Today
• Industry and nanotechnology
– Stain resistant pants (nanofibers blocks the
stains)
– CPU (Moore’s Law)
– Glare-reducing and fog-resistant coatings
– Improved cosmetics and sunscreens
– Tennis rackets (lighter and stronger due to
nanotubes)
Nanofunding
• NNI (National Nanotechnology Initiative)
$849M was requested in 2004 (10% more
than 2003)
• Nanotech Companies ~1335 (www.nanovip.com)
• Lux Research a New York consulting
company estimates that $2.6 trillion worth
of products by 2014.
The Article
• Part 1: making catenane
– Before: long synthetic routes.
– Now: elegant short strategies.
– Obtain interlocking rings by Cu(I)-complex
template.
• Part 2: Creating a muscle-like compound
– Use Cu(I)-complex to create rotaxane that will
mimic a muscle in funtion.
Synthesis of Catenanes
•Cu(I) ions and dpp4
prove to associate
ideally.
•Reaction with the precatenane with the diiodo
derivative of
pentaethylene glycol led
to Cu(1)+ form.
Free the Metal
•The metal free
[2]catenane was obtained
by treatment of Cu(1)+
with KCN in acetonitriledichloromethane-water.
•The X-Ray structure
conforms interlocking
rings.
Part 2: Molecular Machine
•3 was synthesized in several steps
from commercially available
compounds.5
•Reaction of 3 with
[Cu(CH3CN)4]PF6 in CH3CN/CH2Cl2
led qualtitatively to 42+ as its PF6
salt.
•This reaction was slow as the
system reached equilibrium
Molecular Machine in Action
By exchanging
the Cu(I) with
Zn(II), the
complex will
expand and
contract.
From (CPK)
model est., the
compound
changes ~27%.
Conclusion
• Strategies based on phenanthroline-type ligands
entwined around Cu(I) centers successful and
proven effective for preparing gram quantities of
canenanes and rotaxanes.
• New approach using RCM to form the
macrocyclic structures eliminates difficulties with
the Cu(1)+ formation.
• Rotaxanes muscle-like molecule was
synthesized and modeled to show expansion by
CPK modeling.
• This represents the first unimolecular linear array
able to stretch and contract at will under the
action of a chemical stimulus.
Future Work
• Continue research on RCM to synthesis
catenanes and rotaxanes.
• Acquire experimental data to prove the
expansion and contraction of their rotaxane
muscle.
References
1.
2.
3.
4.
5.
6.
7.
www.feynman.com
www.foresight.org
www.imm.org
Belfrekh, N.; Dietrich-Buchecker, C.; Sauvage, J.;
Tetrahedron Letters 2001, 42(15), 2779-2781
Jimenez-Molero, M. C.; Dietrich-Buchecker, C.;
Sauvage, J.; Chem. Commun., 2003, 1613-1616
Drexler, K. E.; Engines of Creation: The Coming Era of
Nanotechnology. New York: Anchor Press/Doubleday.
Drexler, K. E.; Nanosystems: Molecular Machinery,
Manufacturing, and Computation. New York: John
Wiley & Sons.
Questions
Notes/Ideas
• Democritus
Year of Introduction
Transistors
4004
1971
2,250
8008
1972
2,500
8080
1974
5,000
8086
1978
29,000
286
1982
120,000
Intel386™ processor
1985
275,000
Intel486™ processor
1989
1,180,000
Intel® Pentium®
processor
1993
3,100,000
Intel® Pentium® II
processor
1997
7,500,000
Intel® Pentium® III
processor
1999
24,000,000
Intel® Pentium® 4
processor
2000
42,000,000
Intel® Itanium®
processor
2002
220,000,000
Intel® Itanium® 2
processor
2003
410,000,000
www.intel.com
Nanotechnology by Region
Nanotechnology Patents per region
Nanotechnology in the
world—Government
funding (NSF estimation)