Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 41, 2014
Previous Article Next Article

Heavy atom tunneling in the automerization of pentalene and other antiaromatic systems

Author affiliations

Abstract

Cyclobutadiene is a well-known system that can automerize (i.e. undergo a π bond-shifting) by a heavy atom tunneling mechanism. To understand the rules that allow this process, a theoretical study has been carried out on the contribution of tunneling to the automerization reactions of several other molecules with antiaromatic π systems: pentalene, heptalene, acepentalene, and substituted pentalenes. The calculations find that automerization of molecules such as pentalene, which have planar structures, are most likely to proceed by rapid carbon tunneling from the lowest vibrational state, since such molecules have relatively low activation energy and narrow barriers. However, if a molecule is not planar (thus formally “non-aromatic”) and/or requires large geometry changes in order to reach the automerization transition state, then the tunneling will be strongly hindered. In some cases, such as heptalene and tri-tert-butylpentalene, the rearrangement of the reactant requires a modest amount of thermal energy, which can be followed by the π bond-shifting through a tunneling mechanism (“thermally activated tunneling”).

Graphical abstract: Heavy atom tunneling in the automerization of pentalene and other antiaromatic systems

Back to tab navigation

Supplementary files

Article information


Submitted
13 Mar 2014
Accepted
02 May 2014
First published
05 May 2014

RSC Adv., 2014,4, 21650-21656
Article type
Paper
Author version available

Heavy atom tunneling in the automerization of pentalene and other antiaromatic systems

S. Kozuch, RSC Adv., 2014, 4, 21650
DOI: 10.1039/C4RA02191F

Social activity

Search articles by author

Spotlight

Advertisements