Pi Bonds Going All the Way Around a Ring

Whenever we have alternating double and single bonds, we refer to the alternating bond system as conjugated  

When we have a conjugated system that wraps around in a circle, then we can always move die electrons around in a circle  

It does not matter whether we push our arrow s clockw ise or counterclockwise (either way gives us the same result, and remember that the electrons are not really moving anyway). 

Now we are ready to go back to some problems. Let s try to draw resonance structures again. Only this time, let s try to focus on recognizing some patterns. Look at the examples below, and see if you can recognize any of the patterns we just discussed  

A pi bond between two atoms, where one of those atoms is electronegative. 

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