About Us
Recent articles
Fascinating Facts
Contact Us

Importance of Annulenes

Two electron systems
  • Huckel rule predicts cyclopropenyl cation to be aromatic. It has two electrons (n=0) involved in cyclic delocalisation.
  • Many stable substituted systems have been prepared. Among others the trichloro, diphenyl, and dipropyl derivatives are known.
  • Tricyclopropyl cyclopropenyl cation is one among the more stable cations known.
Annulenes - Two Electron System, 2 Annulenes

Four electron systems

  • A closed loop of 4n systems is anti aromatic, less stable than the corresponding open chain counterpart.
  • They have been studied by trapping them in solid matrices at low temperatures.
  • Substituted cyclobutadienes of varying degrees of stability have been prepared.
  • These molecules are relatively stable because dimerisation is sterically hindered.
  • Annulenes - Four Electron System, 4 Annulenes

    Six electron systems

    Annulenes - Six Electron System, 6 Annulenes
    Copyrights: 2005 www.chemvista.org All Rights Reserved
    Home | Recent Articles