H3C-H vs. R3C-H, which is a stronger bond?

[johnwandering]

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I am kind of confused by this scenario.

The R3C-H bond should be much stronger, considering the attached alkyl groups are electron donating... hence strengthening the bond.

However, a tertiary carbocation is much more stable than a methyl cation.



Any thoughts?

 

[chiddler]

I am kind of confused by this scenario.

The R3C-H bond should be much stronger, considering the attached alkyl groups are electron donating... hence strengthening the bond.

However, a tertiary carbocation is much more stable than a methyl cation.



Any thoughts?

should be weaker. EDG make stuff more acidic. click.

ask if you need more explanation.

 

[johnwandering]

EDG make stuff more acidic.

Could I get more information on this?

1.) EN groups make compounds more acidic.
2.) EDG stabilize alkene double bonds.

Why are these traits ignored?

 

[chiddler]

Could I get more information on this?

1.) EN groups make compounds more acidic.
2.) EDG stabilize alkene double bonds.

Why are these traits ignored?

click for #1.

for #2, that doesn't apply because this is not an alkene.

 

[syoung]

terrible handwriting 😛

 

[folktale]

EDG makes stuff more acidic?? Huhh?? I thought it's the other way around?

 

[chiddler]

crap. i mixed it up.

EDG makes stuff less acidic. EWG makes stuff more acidic.

my gorgeous drawing illustrated it correctly though. and my example that i linked with wolframalpha.

sorry.

 

[folktale]

Back to the topic, I think that the stability of the tertiary carbocation and the stronger bond of R3C-H is correct. What is the confusion here??

The tertiary carbocation is more stable because the EDG methyl groups will help diminish the positive charge on the carbocation, and on the R3C-H, the C-H bond is strengthened by the same EDG methyl groups. Both are more stable than the methyl cation and H3C-H, respectively.