All Questions
Tagged with carbocation nucleophilic-substitution
17
questions
2
votes
0
answers
37
views
Relation between formation of carbocation and availability of nucleophile
Many sources suggest that in SN1 reactions the leaving group first exits the molecule, and the resulting carbocation is subsequently attacked by the nucleophile, suggesting that there is no relation ...
- 161
0
votes
1
answer
51
views
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
1
vote
0
answers
311
views
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-...
- 11
3
votes
3
answers
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
2
votes
1
answer
449
views
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 ...
- 69
1
vote
1
answer
136
views
Carbocation stability + determining position of attack on a carbocation in SN1 reaction
It's implied that the right structure is the more stable carbocation because it undergoes the second half of an SN1 reaction, but I'm not entirely sure why:
I'm also not sure why the $\ce{MeOH}$ ...
- 101
3
votes
1
answer
479
views
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
3
votes
1
answer
404
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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, ...
5
votes
1
answer
427
views
What is the product of reaction between 3,3-dimethyl butanal and SeO2 followed by conc. OH- ions?
So basically first step will be replacement of $\ce{-CH2 -}$ by a ($\ce{=O}$ bond) making a aldehyde and ketone side by side. Now what should I do after this? I tried attacking the aldehyde first as ...
- 517
3
votes
1
answer
175
views
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 ...
11
votes
1
answer
1k
views
Is isobutyl chloride or ethyl chloride more reactive in an SN1 reaction?
Compare the rate of $\mathrm{S_N1}$ reaction in the following compounds:
We see that both compounds form primary carbocations. However, there is more hyperconjugation in the second compound as ...
- 745
1
vote
0
answers
850
views
Effect of solvent polarity on SN1 reactions of different charge types
On the topic of the ionisation mechanism (i.e. $\mathrm{S_N1}$), Carey & Sundberg (2007) discuss the effect of polarity of solvent on the rate of $\mathrm{S_N1}$ reactions of different charge ...
- 10.7k
4
votes
2
answers
1k
views
Determining the stereochemistry of the product(s) when an alkyl shift in a carbocation generates a chiral carbon
Consider this carbocation:
We know that this carbocation would immediately rearrange - by a methyl shift - to form the more stable carbocation.
Now, notice that the migration will produce a chiral ...
- 9,881
3
votes
0
answers
5k
views
Nucleophilic Substitution rate comparison 1-bromobutane and 2-bromo-2-methylpropane with NaOH
I want to ask a question about the hydrolysis of haloalkanes to form alcohols.
I have been presented with a flowchart diagram of possible reactions of haloalkanes below:
Now, I have been presented ...
- 1,230
9
votes
1
answer
2k
views
What is the reaction mechanism of nitrogen leaving from diazo compounds?
When a diazo compound is formed, and then a nucleophile is added to the mixture. Will nitrogen gas leave first or will the nucleophile have to "do" a substitution reaction? What I mean is will the ...
- 151