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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: anay on January 20, 2018, 06:15:15 AM

Title: Aromaticity in Resonance structures
Post by: anay on January 20, 2018, 06:15:15 AM
 c1-c(=o)-c=1>>c2-[c+]([-o])-c=2
(the single arrow shows resonance, I couldn't put a double arrow however I tried)
Hi,
I want to know if the compound on the right is a major contributor in the above resonance. I thought it is not, as carbon atom has an incomplete octet, but the answer given is yes, it is a major contributor. Some of my friends said it is because of Aromaticity in the ring, but I tried searching online and couldn't find anything saying that aromaticity in a resonance structure makes it a major contributor. So, I am asking here. How does Aromaticity help in significance of resonance structures? Any refrences/links with an explanation would be appreciated.
Thanks.
Title: Re: Aromaticity in Resonance structures
Post by: sjb on January 23, 2018, 05:59:05 AM
See e.g. http://www.quirkyscience.com/cyclopropenone-aromatic/  or https://en.wikipedia.org/w/index.php?title=Aromaticity&oldid=817768478 for definitions and discussions around aromaticity