More alkyl groups you're attached to means you are more energetically

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Discussion Overview

The discussion revolves around the relationship between the stability of carbocations, specifically tertiary carbocations, and their reactivity in chemical reactions involving alkenes. Participants explore the implications of stability on reaction rates and activation energy, seeking to clarify the underlying principles of chemical kinetics.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants assert that more alkyl groups attached to a carbocation increase its stability, with tertiary carbocations being the most stable.
  • There is a proposal that the increased stability of carbocations correlates with increased reactivity, though the reasoning behind this relationship is questioned.
  • One participant suggests that less stable carbocations, such as primary ones, may revert to their original form, thus deterring reactions.
  • Another participant emphasizes that the stability of the intermediate ion influences the activation energy of the reaction, although the connection between activation energy and the intermediate ion remains unclear to some.
  • Clarification is sought regarding the specific reaction type being discussed, with a suggestion that it may involve electrophilic reactions with alkenes.
  • A later reply indicates that the rapid formation of stable carbocations, rather than their reactivity, is what limits the reaction velocity.

Areas of Agreement / Disagreement

Participants express confusion and seek clarification on the relationship between stability and reactivity, indicating that there is no consensus on this topic. The discussion remains unresolved regarding the specifics of the reaction and the implications of activation energy.

Contextual Notes

Participants note the need for clearer definitions and specifics regarding the reactions being discussed, as well as the potential for misunderstanding due to the phrasing of questions. The relationship between activation energy and the stability of intermediate ions is also highlighted as an area needing further exploration.

Kurokari
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In alkenes, the more alkyl groups you're attached to means you are more energetically stable, and that we know the reactivity increases as the stability of the intermediate carbocation increases (with tertiary the most stable)

I'm puzzled by this relationship, how is it that when it is more stable, the reactivity increases.

I suspect that it is because when a primary carbocation is less stable, it tends to revert back to its previous form, thus deterring the reaction while a tertiery carbocation is more readily formed and react with other substances.

I would appreciate it deeply if anyone who can clear my doubts :)

EDIT: There was a mention that the stability of the intermediate ions governs the activation energy for the reaction. (It would be nice to explain this line too!)
 
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Maybe you can formulate your question more clearly. First you mention stability of alkenes, then you talk of carbocations and then you are taking about some unspecified reaction.
For some basic chemical kinetics, this article in wikipedia may be a starting point:
http://en.wikipedia.org/wiki/Transition_state_theory
 


I'm sorry for the poorly-phrased question, give me another try at this.

An intermediate ion with tertiary carbocation is the most stable right? This is because it has the most alkyl group attached to it, thus making it stable.

There is also a mention that the more stable the intermediate ion(that is the tertiary carbocation in this case) is, the better the reactivity(means the faster it reacts). I'm confused how is it that a more stable compound can be more reactive.

Also there is a line that says that the intermediate ion governs activation energy, I feel that this line may help me understand my question better, however I fail to see any significant relationship between the activation energy and the intermediate ion.

I hope this is better.
 


I asked you to specify the reaction you have in mind. I suppose you are taking about some reaction of an alkene with an electrophilic.


Kurokari said:
An intermediate ion with tertiary carbocation is the most stable right? This is because it has the most alkyl group attached to it, thus making it stable.
Yes
There is also a mention that the more stable the intermediate ion(that is the tertiary carbocation in this case) is, the better the reactivity(means the faster it reacts). I'm confused how is it that a more stable compound can be more reactive.
The point is not that the carbocation reacts more rapidly but that it is formed more rapidly which is the step which limits the velocity of the reaction.
 

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