In question 5 i think option C should be answer but answer key says option B is correct
Why not B ? It's got phenyl resonance(even though it's 2°)
Do you guys have any theory regarding it. I have read only that 3° gives the fastest reaction never encountered this type of questions
aromaticity is dominating factor alawys..
Carbocation is formed in the reaction and we need to see its stabality.
Thats why 3degree gives instantly and 1 degree does not happen
So what will be your choice of answer
@Sneha_2021 I do not agree with you aromatocity is not dominating factor always, Chemistry is known for exceptions and there are many cases where aromatocity is neglected.
Yeah, In lucas test carbocation is formed. So, now this question becomes more difficult as some people say that 3° carbocation is more stable and some says phenyl carbocation!!
I would have marked B as it is reso stabalized carbocation
can u give me any example where aromaticity is neglected @Gaurav_2020_3 i m willing to know
There is no Br in question.......
please apologise me all i was answering question 4 as both i saw that question only
option b is correct i m so so sorry
resonance will make it more stable..
@Ritwik_2019 thanks for pointing my error..
That is taken into consideration when you are comparing 3degree vs 2 degree vs 1degree , whiteout any other factors affecting .
Here , clearly option B is correct because of resonance
At first place , Here , there is nothing related to aromaticity , it’s just that the C+ is in resonance nothing else , C+ stability due to aromaticity is said when due to formation of C+ the ring becomes aromatic .
Here the C+ is stabilised due to resonance, not aromaticity
You might got my post wrong @Shwetanshu_2018 I know aromatocity is not related to this question, I just want to say my point to Sneha that aromatocity is not **Always ** dominant.
Now coming to the question, I still feels the doubt because of several discussions in our class about carbocation stability among the 3° and phenyl!! Are you sure that phenyl carbocation will be more stable in every case!!
I know that in your notes or class you must have been taught separately (as an exception) that among benzyl and t-butyl carbocations , t-butyl carbocation is more stable, but mostly this fact is never used in jee , because there is very less energy differences between the two , until and unless it is specifically asked just to test this knowledge of yours , never ever try to apply this in any question .
During my preparation, even i landed with few wrong answers because I considered this , and then when I discussed with my teacher, he told me , that somewhere in you mind keep that exception in you mind , but in general questions , never use it , rather use resonance > hyperconjugation
Oh!!! Thanks. You were right it is in my notes.