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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Hydrogen isotope effect on methyl shift
Consider this typical 1,2 methanide shift in a carbocation:
Which isotopic form of methanide ($\ce{CH3, CD3, or CT3}$) would migrate from secondary carbocation to form more stable tertiary ...
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Comparing stability of CF3+ and CD3+ [duplicate]
This is a question from my text book.
Compare the stability of carbocation between $\ce{CF3^+}$ and $\ce{CD3+}$.
The answer is given $\ce{CF3+}$ due to backbonding.
But I see backbonding as a sort ...
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Strength of nucleophiles among SN1 and SN2 reactions [closed]
As per the theory of chemistry, we say that unstable carbocations undergo SN2 reactions as it involves strong nucleophile. As a consequence, it does not lead to the formation of reaction intermediate, ...
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Acids used in Friedel-Crafts alkylation
I am learning adding alkyl groups to benzene using Fridel-Crafts alkylation:
I know that it is very common to use $\ce{AlCl3/AlBr3}$ as Lewis acid catalyst in this reaction. But I am just wondering ...
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Order of rate of acid catalysed dehydration of alcohols
The relative rate of acid catalysed dehydration of following alcohols would be:
According to me, we have to arrange them in order of their carbocation stability.
Q will be the most stable as it is ...
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Why do electron-rich aryl groups have greater migratory aptitudes?
In the following reaction there are three possible aryl groups that can migrate: an unsubstituted phenyl group, a p-methoxyphenyl group, and a p-nitrophenyl group:
Why does the electron-rich p-...
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Comparison of carbocation stability in bicyclo compounds
Question
Which is the most stable carbocation ?
Answer
My attempt
I answered as 1 as the first one had +M of -O- and hyperconjugation effect as the positive charge is at para position. Why is the ...
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Reaction of styrene oxide with hydrogen iodide
The question is to find the product of the reaction of Styrene Oxide with Hydrogen Iodide.
According to me, this should be the mechanism-
As the benzylic carbocation will be more stable, therefore ...
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Stability of free radicals [closed]
If given a question to compare stability of free radicals, can we always check it by same parameters that we use for stability of cations (since both are electron deficient) or is there any exception ...
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Stability of carbocations with -M groups in beta position
First part
The original question was to arrange the following compounds in the order of their rate of dehydration with conc. $\ce{H2SO4}$:-
(A) $\ce{CH3-CH(OH)-CH2-CH=O}$
(B) $\ce{CH3-CH(OH)-CH2-C(=O)...
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Hyperconjugation and inductive effect on carbocations [duplicate]
(I know there are many related questions, so please tell me which posts can solve my doubts before you close this question, thank you.)
$1$. $\ce{^+CH2F}$ is very unstable. This is because $\ce{F}$ ...
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Rate of solvolysis of allyl and alkyl halides
Suppose I have 2 compounds, 3-chloropropene and 1-bromo-1-methylcyclohexane. Without knowing the values, how can we compare the rate of solvolysis?
My attempt: Resonance is quite dominant character ...
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Stability of α-chlorocarbocations
I'm trying to compare the relative stability of two carbocations:
$$\ce{CH3-\overset{+}{C}H-Cl}\quad\text{vs}\quad\ce{CH3-\overset{+}{C}H2}$$
Does the $\ce{Cl}$ exert a +M effect to stabilise the ...
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Why does ring contraction take place in Wagner–Meerwein rearrangement?
An example of Wagner–Meerwein rearrangement given in my textbook is substitution by $\ce{AgNO2}$ in iodocyclohexane. One of the product, cyclopentylnitromethane is through ring contraction.
I don't ...
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Addition of HBr on alkene
In 1-chloroprop-1-ene(E), if we add HBr, where will the proton add to, C1 or C2? I am asking this because I can't decide whether mesomeric as well as negative inductive effect of Cl will dominate or ...
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