Linked Questions
14 questions linked to/from Why are vinylic and arylic carbocations highly unstable?
-1
votes
2answers
253 views
Perpendicular orbitals in aryl and vinyl carbocations? [duplicate]
This point (iv) has been given under reasons for extremely low reactivity of aryl and vinyl halides. I cannot understand it. First of all, isn't the positive carbon atom in phenyl as well as vinyl ...
0
votes
0answers
55 views
Resonance in benzenylium cation [duplicate]
Why is this type of resonance not possible? My book says that the positive charge is localised, and resonance is not possible.
But I have drawn the resonance structures (though you can note that the ...
0
votes
0answers
20 views
Stability of carbocation on doubly bonded carbon [duplicate]
What can be said about the stability of the following carbocation?
I think that it would have something to do with hybridisation as, clearly one carbon is sp hybridised and the other is sp2.
Can ...
26
votes
2answers
3k views
Which of the following is the more stable carbocation?
Which of the following is the more stable carbocation?
I thought the 1st carbocation would be the more stable one as the pi-electron density of phenyl group can overlap with the vacant orbital on ...
11
votes
2answers
11k views
Why are sp hybridized carbocations high energy?
You don’t see carbocations on double bonds very much, and here's a good reason: compared to sp3, there is more s character in the orbitals, so the empty orbital is held more closely to the nucleus. ...
25
votes
2answers
25k views
Carbocation stability order
I was wondering whether the following order (from here) is correct:
In the first inequality, why did 9 hyperconjugations dominated resonance effect of benzene ring?
In the last inequality doesn't ...
25
votes
1answer
789 views
Do vinyl cations adopt a classical or non-classical structure?
Whilst reading this question today, I remembered something that I had seen previously here. In the second linked question, @Martin provided a reference to suggest that vinyl cations actually adopt a ...
3
votes
2answers
355 views
Alkenes v/s Alkynes in two different reactions
Alkynes are less reactive towards electrophylic addition than alkenes. However, in case of catalytic hydrogenation, alkynes are said to be more reactive. Why? Also, if I want to add H+ as an ...
-2
votes
1answer
347 views
On the stability of carbocations
I have a question regarding the stability of carbocations. It is shown below.
I am confused between options II and III. The structure shown in option II has more resonance structures. Thus, I ...
2
votes
0answers
154 views
Stability of the alkenyl and phenyl cations
One reason often cited for why alkenyl and phenyl halides do not undergo nucleophilic substitution by the $\ce {S_N1}$ mechanism is that the formation of the alkenyl and phenyl cations involve a ...
0
votes
1answer
71 views
Acidic cleavage of an ether
In the following question;
Apparently, an SN2 reaction ensues, where the iodine atom's supposed to cleave off with the less sterically hindered alkyl branch from both the oxygens. This is the ...
1
vote
0answers
115 views
Why is SN1 mechanism followed in diazo aromatic compounds' nucleophilic substitution?
There is considerable evidence that SN1 mechanism is followed in diazo aromatic compounds' nucleophilic substitution. I would like to know the reason for this and why is it preferred to SNAr mechanism ...
1
vote
0answers
80 views
Accounting for Vinylic Carbocation instability [closed]
I read that due to geometrical constraint, positive carbons in an aryl carbocation exhibit sp^2 hybridization instead of sp^1. The empty p-orbital is forced into a hybridized position via geometrical ...
2
votes
0answers
62 views
Organic chemistry, hybridization concept [closed]
Hybridization of phenyl cation and venyl[sic] vinyl cation and acetylene cation ,I am totally confused , I think that the hybridization of both phenyl and the venyl cation is SP , I think that in both ...