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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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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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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Why are tertiary carbocations the most reactive, if they're already stable?
This may seem silly, but doesn't it seem weird for a compound that's stable (in this context, the tertiary carbocation) to be the most reactive?
I mean, wouldn't it be the least, given that it's ...
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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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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 ...
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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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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 ...
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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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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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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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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 ...
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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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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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Precedence of 1,2 carbocation rearrangement
How can one choose which group has more shifting tendency in 1,2 carbocation rearrangement? The obvious order is via the stability of the carbocation of the group. But, phenylic groups have high ...
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