November 27, 2024, 03:44:16 PM
Forum Rules: Read This Before Posting


Topic: Aromaticity (complex compounds)  (Read 2094 times)

0 Members and 2 Guests are viewing this topic.

Offline Rutherford

  • Sr. Member
  • *****
  • Posts: 1868
  • Mole Snacks: +60/-29
  • Gender: Male
Aromaticity (complex compounds)
« on: May 04, 2013, 07:55:39 AM »
How is the attached compound aromatic? I can't see the conjugated system expanding from the three benzene rings. They look to me like separated with two sigma bonds from each other. Need an explanation.

Offline Dan

  • Retired Staff
  • Sr. Member
  • *
  • Posts: 4716
  • Mole Snacks: +469/-72
  • Gender: Male
  • Organic Chemist
    • My research
Re: Aromaticity (complex compounds)
« Reply #1 on: May 04, 2013, 10:34:55 AM »
The compound has three aromatic rings, but as you point out they are not conjugated with each other. For a compound to be aromatic it need as least one aromatic system, but it could have more.

My research: Google Scholar and Researchgate

Offline Corribus

  • Chemist
  • Sr. Member
  • *
  • Posts: 3551
  • Mole Snacks: +546/-23
  • Gender: Male
  • A lover of spectroscopy and chocolate.
Re: Aromaticity (complex compounds)
« Reply #2 on: May 04, 2013, 12:10:00 PM »
Compounds like this are thought to manifest a special type of aromaticity called Mobius aromaticity.

See: http://en.wikipedia.org/wiki/M%C3%B6bius_aromaticity

The prototype compound, very similar to the one you have here, is barrelene:

http://en.wikipedia.org/wiki/Barrelene
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman

Offline Rutherford

  • Sr. Member
  • *****
  • Posts: 1868
  • Mole Snacks: +60/-29
  • Gender: Male
Re: Aromaticity (complex compounds)
« Reply #3 on: May 04, 2013, 01:32:10 PM »
Thanks for the help.

Sponsored Links