Êtes-vous un étudiant de l'EPFL à la recherche d'un projet de semestre?
Travaillez avec nous sur des projets en science des données et en visualisation, et déployez votre projet sous forme d'application sur Graph Search.
Concept
Pi-interaction
Résumé
In chemistry, π-effects or π-interactions are a type of non-covalent interaction that involves π systems. Just like in an electrostatic interaction where a region of negative charge interacts with a positive charge, the electron-rich π system can interact with a metal (cationic or neutral), an anion, another molecule and even another π system. Non-covalent interactions involving π systems are pivotal to biological events such as protein-ligand recognition.
The most common types of π-interactions involve:
Metal–π interactions: involves interaction of a metal and the face of a π system, the metal can be a cation (known as cation–π interactions) or neutral
Polar–π interactions: involves interaction of a polar molecule and quadrupole moment a π system.
Aromatic–aromatic interactions (π stacking): involves interactions of aromatic molecules with each other.
Arene–perfluoroarene interaction: electron-rich benzene ring interacts with electron-poor hexafluorobenzene.
π donor–acceptor interactions: interaction between low energy empty orbital (acceptor) and a high-energy filled orbital (donor).
Anion–π interactions: interaction of anion with π system
Cation–π interactions: interaction of a cation with a π system
C–H–π interactions: interaction of C-H with π system: These interactions are well studied using experimental as well as computational techniques.
Metal–π interactions play a major role in organometallics. Linear and cyclic π systems bond to metals allowing organic complexes to bond to metals.
Ethylene – π
In the most simple linear π systems, bonding to metals takes place by two interactions. Electron density is donated directly to the metal like a sigma bond would be formed. Also, the metal can donate electron density back to the linear π system (ethylene) from the metal’s d orbital to the empty π* orbital of ethylene.
Allyl–π
Allyl groups can bond to metals as trihapto or monohapto ligands. Monohapto ligands bind mostly sigma orbitals and trihapto ligands bind using delocalized π orbitals.
Source officielle
À propos de ce résultat
Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.