Questions tagged [carbocation]
Carbocations are species bearing a positive charge on carbon. They are intermediates generally formed during organic reactions, which can be stabilised by various electronic effects. Less stable carbocations are capable of undergoing rearrangements to form more stable carbocations in the course of a reaction.
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What is the reason for the exceptional stability of the cyclopropylmethyl carbocation?
Can someone explain this to me by drawing resonance structures for the cyclopropylmethyl carbocation please?
Also one more question, is the tricyclopropylmethyl carbocation more stable than tropylium ...
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Why are vinylic and arylic carbocations highly unstable?
I have checked the internet and read quite a few books, but I still am not able to understand why vinylic and arylic carbocations are highly unstable.
What I found while surfing the internet is: For ...
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Which carbocation is more stable, the ethyl- or 1-propyl-carbocation?
$\ce{C2H5+ vs \ C3H7+}$
There are two conflicting trends here.
Inductive effect of ethyl will be higher than that of methyl so carbocation attached to ethyl (3 carbons in total) should be more stable....
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Is the t-butyl carbocation more stable than the benzyl carbocation?
Various authors have different views regarding stability order of the benzyl and t-butyl carbocations.
$$\ce{PhCH2+ ; (CH3)3C+}$$
In my opinion, resonance effect dominates, so the benzylic ...
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Ring contraction in a carbocation due to ring strain and back bonding
Today our teacher told us that the following carbocation rearrangement occurs due to back bonding. I could not really follow what he meant. Can someone please explain what is actually happening during ...
user14857
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Stability of carbocations: CF3+ vs CH3+
Is $\ce{CF_3+}$ more stable than $\ce{CH_3+}$?
In $\ce{CF_3+}$, there is $\ce{C-F}$ back bonding that increases stability of the carbocations. But -I effect of $\ce{F}$ dominates +R effect and this ...
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What is a non-classical carbocation?
What is a non-classical carbocation?
How is it different from a classical carbocation?
I am confused as I have come across this term many times on Chem.SE but there seems to be nothing for my level ...
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Stability Comparison between the Tropylium and Tricyclopropylcarbinyl Carbocation
Why is the Tropylium carbocation less stable than the tricyclopropylcarbinyl carbocation? The tricyclopropylcarbinyl carbocation undergoes a sigma-tropic rearrangement whereas tropylium is highly ...
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Migratory aptitude in pinacol-pinacolone rearrangement
I am confused about the migratory aptitude of various groups, as there are many different orders for the same given in different places, especially about -Ph and -H. I would like to know if someone ...
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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 ...
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Will bridged compounds the undergo SN1 reaction?
$\mathrm{S}_{\mathrm{N}}1$ reaction involves only one molecule in the rate determining step. So, the molecule which undergoes $\mathrm{S}_{\mathrm{N}}1$ reaction should be stable when it forms a ...
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Stability of cyclobutyl methyl carbocation
I know that cyclopropyl methyl carbocation is exceptionally stable compared to say, benzyl carbocation.
But I want to know how stable is cyclobutyl methyl carbocation compared to say, tertiary/...
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Confused about carbocation stability
For which element 'X' is the carbocation $\ce{CH3-X-CH2+}$ the most stable?
A. X = S
B. X = N
C. X = O
I thought since oxygen is the most electronegative among the options, it would create the ...
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Unusual Friedel–Crafts alkylation with pivaloyl chloride
In class we were told of an anomalous Friedel–Crafts reaction with a tertiary acid chloride — $\ce{(CH3)3CCOCl}$, or pivaloyl chloride. When this reacts with benzene in the presence of $\ce{AlCl3}$, ...
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Can hydride shift and methyl shift happen one after another in a carbocation?
Can a hydride shift be followed by a methyl shift for stabilizing a carbocation?
In case both are possible, which will occur first?
user14857