Aromatic question

[kingseven]

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Hey guys, I was doing Chad's aromatic quiz and I don't understand why I got this question wrong. Can anyone please explain this to me. Thanks

 

[virajpatel]

Well the oxygen has 2 lone pairs and one of them contributes to the structure giving it 6 pi electrons thereby following Huckels rule and the plus charge on the carbon indicates that it is sp2. So since it is cyclic, planar, sp2 and obeys huckels rule you can determine that it is aromatic.

 

[DatRav27]

Since the lone pairs (pi electrons) on the oxygen are not associated with a double bond, they are able to participate in resonance. Therefore the 4 delocalized electrons in the ring and 2 from the oxygen make a total of 6 delocalized electrons able to perform resonance. With the help of the "+" charge on the allylic carbon, the molecule is an aromatic compound

 

[kingseven]

I was first thinking about the lone pairs on the oxygen and then i was like since its not mentioned I should look at it without the lone pairs. But I guess on the real DAT you have to be careful even if the lone pairs are not mentioned. Thanks guys