1. Nanochemistry NAN 601 Dr. Marinella Sandros
Instructor:
Dr. Marinella Sandros
Lecture 8: Supramolecular Chemistry

2. What is Supramolecular Chemistry ?
“Supramolecular chemistry is the chemistry of the
intermolecular bond, covering the structures and
functions of the entities formed by the association
of two or more chemical species”
J.-M- Lehn
"Supramolecular chemistry is defined as chemistry
‘beyond the Molecule’, as chemistry of tailor
shaped inter-molecular interaction.”
F. Vögtle

3. What is Supramolecular Chemistry?
“Chemistry beyond the molecule”
“Chemistry of molecular assemblies and of the intermolecular bond.”
“The Chemistry of non-covalent bond.”

4. Molecules Supermolecules
Supramolecular chemistry involves investigating molecular systems in which the most important feature is that components are held together by intermolecular forces, not by covalent bonds.
Atoms Molecules
Molecules Supermolecules
Covalent Interactions
Non-Covalent Interactions

5. Supramolecular Chemistry

6. Supramolecular Chemistry
Where did it come from?
Inspired from biology and built on the shoulders of traditional synthetic organic chemistry.
Why does it deserve to be a field of study all its own?
The next logical step in synthetic chemistry; understanding and interface with the biological world; nanotechnology

9. Lock and Key Principle

11. Beyond Host/Guest Chemistry
Molecular Self-Assembly:
Process by which 2 or more molecules interact from a larger structure or organization.
Super-Molecule:
A complex formed by molecular self- assembly which contains a discrete number of subunits.

12. Covalent Bond Energies

13. Non-Covalent Interactions: Electrostatic

14. Hydrogen-Bonded Interactions

15. Hydrogen Bond

16. -  Interactions

17. Dispersion Forces

18. Hydrophobic Effect

19. Coordination Bonds

20. Supramolecular: Biology
The study of non-covalent interactions is crucial to understanding many biological processes from cell structure to vision that rely on these forces for structure and function. Biological systems are often the inspiration for supramolecular research.

21. Example :DNA

23. How to make a receptor ?
people.bio.aau.dk/.../PowerPoint/Supramolecular%20chemistry.ppt

24. Biotin-Streptavidin
malina.ichf.edu.pl/educ/.../WYKLAD_SUPRA_NANO1_2005.ppt

27. Answer???

30. Forces Involved in Self-Assembly:

31. Interaction Energies

32. Chelate Effect Two donor atoms linked together = a chelate (claw)
Chelate ligands form much more stable metal complexes than monodentate related ligands (up to 105 times as stable)
Ni L Formation Constants:
L = NH3 en trien 2,3,2
better
complementarity
faculty.swosu.edu/tim.hubin/InorganicLects/InorgCh12.2.ppt

33. Chelate Effect Why is favorable??
Thermodynamic Reasons for the Chelate Effect = Entropy

34. Macrocylic Effect
Macrocyclic chelate complexes are up 107 times more stable than non-cyclic chelates with the same number of donors
Ni(trien) H Ni H4trien t½ = 2 seconds
Ni(cyclam) H Ni H4cyclam t½ = 2 years
Connecting all of the donors (having no end group) makes k-2 important
Breaking the first M—L bond requires major ligand deformation
The increase in Ea required greatly slows down k-2
faculty.swosu.edu/tim.hubin/InorganicLects/InorgCh12.2.ppt

35. Macrocylic Effect
The result is a very stable complex as kd becomes miniscule

37. Valinomycin

38. Self-Assembly

39. Supramolecular Assembly
They allow access to nanoscale objects using a bottom-up approach in far fewer steps than a single molecule of similar dimensions.
The process by which a supramolecular assembly forms is called molecular self-assembly. Some try to distinguish self-assembly as the process by which individual molecules form the defined aggregate. Self-organization, then, is the process by which those aggregates create higher-order structures.

41. Self-Organization and Self-Assembly

42. Important Features

43. Molecular Imprinting

44. Imprinted Polymer-coated QCM Sensors

45. Molecular Imprinted Polymers