Is Option 2 the Correct Answer for Huckel's Law?

[Priyadarshini]

Homework Statement

Homework Equations

Huckel's Law: 4n+2=pi electrons

The Attempt at a Solution

I'm not sure what the dash and two dots in the brackets mean, are those lone pair of electrons?
Not including them as pi electrons:
option 1: 4= 4n+2
n=1/2, so no aromatic
option 2: 2= 4n+2
n= 0, so aromatic
option 3: 4=4n+2, n=1/2
so the answer should be option 2?

 

[Suraj M]

I don't know if you were told which electrons to consider when you take the value of n in huckels rule
Does option 1 have just 4 electrons involved in the resonance?

 

[Priyadarshini]

I don't know if you were told which electrons to consider when you take the value of n in huckels rule
Does option 1 have just 4 electrons involved in the resonance?

Doesn't Huckels rule involve pi electrons only? Does it involve all the electrons taking part in the resonating structures?

 

[Suraj M]

Do you think you've considered ALL the pi electrons?

 

[Priyadarshini]

Do you think you've considered ALL the pi electrons?

Oh, but then both option 1 and 3 work out to be aromatic as both have 6 pi electrons.

 

[Suraj M]

Is option 3 even a possible structure? Just look at it
Count the number of electrons on each carbon!

 

[Priyadarshini]

Is option 3 even a possible structure? Just look at it
Count the number of electrons on each carbon!

Ah, I see! Thanks.