All Questions
Tagged with carbocation stability
70
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what role does mesomeric effect and inductive effect play in stability of carbocations in presence of halogens
what should be the ideal explanation behind the order of stability of these three compounds?
Case-1
In these three examples the first two structures have a positive mesomeric effect and it is greater ...
-2
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2
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62
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Stability of phenylic carbocations [closed]
Problem:
Structure (1) is more stable than structure (2).
My teacher stated that Structure (1) is more stable than Structure (2). I find this confusing. How can Structure (1) be more stable when ...
- 131
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281
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Can a carbocation ever be more stable than a neutral molecule?
The question is about finding the most stable molecule or species. Now my thought process was that cyclopropenylidene(1) was a carbene so would be unstable even though it is aromatic. Cyclopenta-1,3-...
- 97
2
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186
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How ring expansion is possible here?
Recently I have came across this question.
I went with the 3rd option as ring expansion cannot occur due to the formed stable 3 degree carbocation. But the answer key claims 4th option. How can ...
- 105
-2
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275
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Stability comparison between tropylium, cyclopropylmethylium and dicyclopropylmethylium cations
Write the correct stability order of the following compounds:
I don't have any concern with estimating stability of (1), only (2), (3) and (4). Our teacher said that unless the carbocation has three ...
3
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3
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229
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Comparing reactivity of 3-bromocyclohexa-1,4-diene and 5-bromocyclohexa-1,3-diene towards SN1 reaction
Compare reactivity of 3-bromocyclohexa-1,4-diene (P) and 5-bromocyclohexa-1,3-diene (Q) towards $\mathrm{S_N1}$ reaction.
My teacher claims that the reactivity of P is more than that of Q. He ...
- 299
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3
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344
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Carbocation Stability question
Arrange, the following carbocation on increasing order of stability:
What have I though is that in second it will be most unstable, as $\ce{-OH}$ group will create most inductive effect (negative), ...
- 195
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132
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Carbocation formation and stability from bromo compounds
When heated,the following bromo-species all form carbocations via $\sigma$ bond cleavage. For each structure draw the corresponding carbocation and briefly describe how it is stabilised.
This is my ...
- 29
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1
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763
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Among Benzyl carbocation (Ph-CH2+) and Methyl methoxy carbocation (CH3-O-CH2+), why is the latter more stable?
Benzyl Carbocation could form multiple conjugation, then why isn't that stabler? In Methyl methoxy carbocation, Oxygen donates the lone pairs but so does the double bond in the benzyl Carbocation.
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287
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Choosing hyperconjugation when resonance doesn't give a reason for stability
Which of the following structures would be least stable?
I initially approached it like this:
As both are allylic carbocations, and that both are in fact resonating structures of the same molecule, ...
- 1,218
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479
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Second-step activation energy in SN1 reactions
In SN1 reactions, it's known that there are generally two steps, with the first being the R.D.S step involving carbocation formation and the next having a lower activation energy.
Why does the second ...
- 1,134
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0
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142
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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 ...
- 1,280
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38
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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 ...
- 119
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2
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1k
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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 ...
- 363
3
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1
answer
643
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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 ...
- 357