Doubt from aromaticity

27 i think it should be D because , in all other cases lone pair of atoms like O,N are required for aromaticity but in case of benzene a complete double bond is available

@Raghav_2020 d is non aromatic

For 33 ) it should be B because there is no complete conjugation

  1. it should be A because there are 2 double bond and 1 vacent orbital of B which act as +ve charge

Oh thanks

Question 34,35,36 and 37 in 34 why b option is not possible

Q34)
Option C should be correct because , only then complete conjugation will take place and the condition of 4n+2 electrons will be fulfilled

Option B is incorrect because with these number of carbon , if you’ll add 2 more double bond then you can’t conjugate them , they will form cumulative allenes instead

  1. it should be A because Alcl3 takes out cl and this leaves a + charge and hence 2 double bond + 1 -ve charge + 1 positive charge forms aromatic compound

  2. it should be A i think ,lone pair of O of OH will attack on H+ of HCL and form H2O+ and it will leave forming + charge and hence compound will become aromatic

  3. it should be B i think , because then + charge will be formed at sp3 position

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How is this aromatic ?

what book is this?

@Raghav_2020 here O has a lone pair(acts like a -ve charge) which will be in conjugation, and B has vacancy (acts like a +ve charge )
Now you can see that there is complete conjugation , and it has 4n+2 pie electrons

But in answer key it says b for 36 and a for 37

@abhijit_2020
In the above post by mistake i have written 36 for 37 and 37 for 36
I.e the explanation that i have written under 36 is actually the explanation for 37 and vice versa ,
You can see , in 36 i have explained why Hcl will be used , it is actually explanation of 37
My bad :sweat_smile:

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Question no 45 can you help in identifying compounds in which i have marked a question mark what are they aromatic,antiaromatic or non aromatic


U meant like this ? But is the compound stable.
There will be a positive charge on O

Why do you think it will be unstable ?

Also in the structure you drew, there will be +on O and - on B

Please help in question 45 i am getting x as 6.5 but its a numerical based and answer should be 6 actually problem is that i am getting 5 antiaromatic compounds but i think 4 would be correct and there are 6 aromatic compounds that is correct please check i have marked what are they

Yes ,understood .
Thanks

@abhijit_2020


the only mistake that you have done is , you have taken this compound as anti aromatic , whereas it is non aromatic

Oh thanks so this compound is non aromatic but it's tautomeric form is antiaromatic

When tautomeric form becomes anti aromatic then it doesn’t prefer to stay in it’s enol form , don’t check whether it’s tautomer is anti aromatic or not , simply check for it’s given form only