All Questions
Tagged with carbocation rearrangements
19
questions
-3
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0
answers
23
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Stereochemistry of Rearrangements of carbocations [closed]
Suppose in a carbocation ,rearrangement of methyl has to to place to a chiral carbon, forming a stabler cation in the process.But what will be the stereochemistry of the rxn? Will the chiral carbon on ...
0
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1
answer
51
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What nucleophilic reaction takes place in case of bad leaving group as well as 1* alpha carbon?
If we add HI to a substrate Ph-C-C-OH what will be the major product and what reaction mechn. will be followed?
My attempt: as -OH is bad Leaving Group, we cannot just simply proceed with Sn2 and ...
- 23
0
votes
1
answer
772
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Carbocation rearrangement with ring expansion
I was solving a particular question which landed me to a position where I have to decide whether the following ring expansion would take place or not by carbocation rearrangement:
If the expansion ...
- 119
3
votes
4
answers
3k
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Hydride shift or Methyl shift
For the carbocation (A) given in the reaction, first we can rearrange it by ring expansion (4 to 5) then we have two choices either H-shift or methyl-shift. My teacher told me that Hydrogen is the ...
- 187
1
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0
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101
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Why doesn't the protonated propyne rearrange? [closed]
In the reaction of propyne with $\ce{HBr}$ this cation (prop-1-en-2-ylium) was mentioned by my teacher:
$$\ce{H3C-\overset{+}{C}=CH2}$$
He told me that the carbocation will not rearrange as it will ...
- 201
-4
votes
1
answer
103
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Does rearrangement occur in schmidt reaction? [closed]
I recently read about schmidt reaction in which a carboxylic acid is converted to an amine. While forming this, acyl carbocation $(\ce{RCO+})$ is formed, so does rearrangement takes place or reaction ...
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5
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0
answers
67
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Why does this carbocation undergo further rearrangement? [duplicate]
I am trying to figure out the product of this reaction. I initially thought that a carbocation would be formed at where the chlorine leaves
from:
But according to the answer stated by the textbook,...
- 421
0
votes
1
answer
93
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Carbocation rearrangement
I am dealing with some basic reactions in organic chemistry. One of these is the acid reflux of alcohols. Something I came across was hydride shifts. I know how and why they occur, but I don't ...
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1
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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
2
votes
1
answer
303
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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 ...
- 421
0
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0
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97
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Which of the following compound will undergo rearangement?
Question
Attempt
I believe the answer should be B,C and D. In C and D the oxyge(or Nitrogen in D) can rearange by donating lone pair to carbocation.
But the books answer says B. Where am I wrong. ...
- 623
1
vote
1
answer
393
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Intramolecular Reaction with carbocation rearrangement
I came across a question recently which is as follows,
I came up with a mechanism but I am stuck at a step as I am unable to reason out the driving force.
Step(3) has a hydride shift and its next ...
- 1,244
3
votes
1
answer
175
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Rearrangement considerations in feasibility of SN1 in given reactants
I have been asked to compare the feasibility of Unimolecular Nucleophilic Substitution ($\mathrm{S_N1}$) in the following question.
I have received instruction that the reaction will be feasible only ...
4
votes
3
answers
1k
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Which ring expansion in cyclobutyl(cyclopropyl)methanol is favourable?
Predict major product:
In this question first I've protonated the OH group and then water is removed to form a carbocation. Now I have to expand the ring, but I'm confused which ring to choose: 3-...
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5
votes
4
answers
352
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8a-methyl-1,2,3,4,4a,8a-hexahydronaphthalen-4a-ylium carbocation rearrangement
In this reaction after the attack of lone pairs on $\ce{H+}$ ions, a stable $3^{°}$ carbocation is formed. But seeing the six membered ring and the double bonds already present, I can't help but think ...
- 355