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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Confusion in carbocation rearrangement
In the above dehydration reaction (asked in a competitive examination) I have shown two paths, obviously only one of them is correct.
According to test correct answer is product formed through A but I ...
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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 ...
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What is the hybridization of the carbon atom in cyclopropenyl carbocation?
The hybridization of the carbocation in the cyclopropenyl carbocation (which is aromatic) should be sp as it as the + and also is in a ring. But the carbocation has a sp2 hybridization, why?
For ...
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Which 1,2-methylene shift is more favourable in ring expansions where ring has substituents
In the above reaction, first the -OH group is protonated after which it leaves creating a carbocation intermediate as shown
Now, ring expansion is a more favourable rearrangement, however there is a ...
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Effect of beta branching and carbocation rearrangement on SN1 reaction rates
My book (NCERT class 12 Chemistry) asks
Predict the order of reactivity of the four isomeric bromobutanes in SN1 and SN2 reactions.
The answer given for SN1 is
1-bromobutane < 1-bromo-2-...
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What kind of rearrangement happens between 2,2,5-trimethylcyclopentanol and concentrated sulfuric acid?
Question:
My attempt:
After getting the carbocation after protonation, in order to form a more stable alkene, it rearranged the methyl group on the adjacent carbon so as to get the alkene in the ...
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Why is the carbocation on the left more stable? [closed]
I assume resonance is coming into play here due to the hydroxy group on the carbon adjacent to the positive charge. What about the electron donating effect of the alkoxy groups?
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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 ...
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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 ...
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On what basis is the rate of Sn1 reaction dependent
Does the rate of reaction depend on the stability of the 1st carbocation formed just after the leaving group leaves or the rearranged carbocation's stability? for eg
Here if i compare the stability ...
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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), ...
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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 ...
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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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Are all chiral carbons sp3 hybridised? [closed]
I had this doubt, whether all asymmetric chiral carbons must necessarily be $\mathrm{sp^3}$ hybridized. For sure, we know that double or triple bonded carbon atoms don't shows such chirality, but is ...
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Stability of meta ethyl and meta methyl benzene carbocations respectively
It is known that Methyl has a greater +I effect than Ethyl, but here, in this case, the condition is satisfied in the para benzene carbocations whereas, in the meta forms, it is the opposite. Shouldn'...
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