Supramolecular Chemistry

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The supramolecular chemistry is a branch of chemistry that deals with the association of molecules busy parent (supra) structures. It deals with processes of self-assembly and the host-guest chemistry ( English host-guest chemistry ) and the resulting supramolecular systems . Knowledge about aggregates of enzymes and their substrates were formative for this area . Interdisciplinary methods from all areas of chemistry and physics are used to research supramolecules . For their contributions, Donald J. Cram , Jean-Marie Lehn and Charles Pedersen were honored with the Nobel Prize in Chemistry in 1987 and also the Nobel Prize in 2016 to Jean-Pierre Sauvage , J. Fraser Stoddart and Bernard L. Feringa related to molecular machines and mechanics interlocking molecules (such as catenanes , rotaxanes ) represent an important area of ​​supramolecular chemistry.

[18] Krone-6, a crown ether

Cram explained host-guest complexes as follows:

“These complexes consist of two or more molecules or ions whose unique structures are held together by forces other than covalent bonds. [...] These electrostatic forces include hydrogen bonds , ion pair formation, acid - base interactions, metal - ligand interactions , Van der Waals forces and hydrophobic interactions. "

The most widely studied classes of compounds in supramolecular chemistry include the crown ethers , the cryptands and cryptates , along with the associated metalla topomers , as well as the cyclodextrins and calixarenes . But inorganic hosts such as zeolites and polyoxovanadates are also possible.

The investigation of these associates pursues several goals: It tries both to provide deeper insights into the nature of enzyme-substrate complexes and to provide access to improved catalysts and analytical methods. Furthermore, supramolecular chemistry strives to synthesize new materials with properties that are as tailored as possible. Mention may be made to molecular machines such as a molecular switch or a synthetic molecular motor . The most important tool of supramolecular chemistry is spontaneous self-assembly (self-grouping) and self-organization .

Metallo-supramolecular chemistry

In the sub-area of ​​metallo-supramolecular chemistry, metal ions are used as important structure-forming assemblies. The structures obtained in this way (for example lattice-shaped metal complexes ) are referred to as metallo- topomers in comparison with the purely organic structures of the same topology .

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