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@Dexter
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option C
Chemistry Stack Exchange
Why is the nitroso group a deactivating group for electrophilic aro...
Does the lone pair of nitrogen in nitrosobenzene take part in resonance? If not, then why? If it takes part in resonance then the hybridisation of nitrogen is sp. Can a sp hybridised atom be attach...
2 different explanations given both convincng
It is -M and a meta director, I suppose.
The reason backing my ans would be since it is a withdrawing group, which would generate +ve charges over ortho and para positions due to resonance.
lone of pair of N can be in conjugation too
For that, it has been said by our teacher that generally, double bond-double bond resonance is more prioritized over lone par-double bond.
why
Nitroso is +M iirc. There is a lone pair on Nitrogen which can be donated.
Nitro is different because nitrogen has an empty p orbital because it gives away the lp with a coordinate covalent bond to oxygen.
I don't really have a reason for this though.
does it make a sure thing that electrons will be withdrawn
yes ig because if oxygen gives electon to N it will
go in the empty orbital
preventing resonanc
If you have a vacant orbital on the ring-connected atom, then yeah, it's for sure EWG
Not happening. Valency of oxygen.
Only time oxygen gives electrons with a dative bond is in carbon monoxide or alike species.
Iirc.
There might be exceptions, but this is not one.
+electronegativity of O
That too. Oxygen does not like sharing.
true
so nitro is for sure ewg
nitroso confusion remains
Nitroso is EDG. Lp on Nitrogen can be donated.
Just like in NH2
nitro (no2) is shows very good -m effect
very good ewg
Nitroso mb. Typo.
but then ans to this will be 4 , (given 3 in module)
fiitjee module so idk bout trusting the key
Then I guess they're using the logic that (-) charge is more stable on oxygen.
Shifting double bond to oxygen
Nitro so is op director
I think it can act as both, ortho-para and meta director, depending over other groups.
In the end the matter is to become more stable/more electron density in ring. Whatever goes best with it would do.
NO is a deactivator but a ortho para director like halogens
with this in regard and following the ans key we can conclude nitroso is meta directing
T-T
nitro is meta directing too
Let me check my class note a etc
Cuz I learnt this pretty sure
Yah it’s given NO I’d a deaftivator of EAS but op
Deactivtaor*
Let me read the question
But this doesnt imply that it shouldn't be considered an o/p director? I suppose.
it tends more towards meta directing nature
I see.
Ans?
given 3
Yah NO is op
It is an exception like halogens
.
Nvm didn’t read the Q fully
Say, I consider a benzene ring with a group having withdrawing characteristic, and NO attached to ortho position. NO here should be donating in nature to increase the electron density in the ring, which is what is favorable. Would be opposite for a donating group being attached with NO.
its both +M and -M btw
depends on the Degree of both of them
if the +M factor is more then it should be o/p
and if -M is more than Meta directing it is
i think that it should deactivate the ring as of total because -I bhi hai
right..