0
$\begingroup$

enter image description here

I have read in Solomon's Fryhle that +I effect of D is more than H but here in this problem it is given that (CH3)3C+ is more stable. How is it possible when Deuterium enriches the electron density over central Carbon resulting in diminishing of + charge eventually making second structure more stable. Second explanation can be on the basis of hyperconjugation which says that -CH3 is better in showing hyperconjugation than -CD3, but WHY? Please explain.

$\endgroup$
3
$\begingroup$

$\ce{C-D}$ bonds are stronger. Hyperconjugation is thus more easily seen with hydrogen rather than deuterium.
Hyperconjugation> Inductive effects at stabilization.I believe you can reason the rest out by yourself.
To see why $\ce{C-D}$ bonds are stronger.
See this

$\endgroup$
  • 2
    $\begingroup$ While true, this answer is extremely unsatisfying. The link from bond strength to hyperconjugation is not obvious to me at all. (And I'm not saying I have any better explanation. This is something which I have never seen a good explanation for.) $\endgroup$ – orthocresol Jan 28 '18 at 18:33
  • 1
    $\begingroup$ @orthocresol Maybe this contains the required answer. $\endgroup$ – Apoorv Potnis Jan 29 '18 at 5:51

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.