Although C-D bond is stronger than C-H bond, yet (CH_(3))_(3)C^(+)(i) is more stable than (CD_(3))_(3)C^(+) (ii) Why so ?

Although C-D bond is stronger than C-H bond, yet (CH_(3))_(3)C^(+)(i)

1.	Although C-D bond is stronger than C-H bond, yet (CH_(3))_(3)C^(+)(i) is more stable than (CD_(3))_(3)C^(+) (ii) Why so ?
Answer» <html><body><p></p>Solution :Both carbocations (i) and (ii) are stabilized by hyperconjugation as shown below: <br/> <img src="https://d10lpgp6xz60nq.cloudfront.net/physics_images/PR_CHE_02_XI_C12_E16_013_S01.png" width="80%"/> <br/> <img src="https://d10lpgp6xz60nq.cloudfront.net/physics_images/PR_CHE_02_XI_C12_E16_013_S02.png" width="80%"/> <br/> Due to stronger C-D bond, <a href="https://interviewquestions.tuteehub.com/tag/contribution-932552" style="font-weight:bold;" target="_blank" title="Click to know more about CONTRIBUTION">CONTRIBUTION</a> of <a href="https://interviewquestions.tuteehub.com/tag/structures-17929" style="font-weight:bold;" target="_blank" title="Click to know more about STRUCTURES">STRUCTURES</a> (V-VIII) towards stability of carbocations, `(CD_(3))_(3)C^(+)` is less than those of structures (I-IV) for carbocation, `(CH_(3))_(3)C^(+)`, therefore, carbocation (i) is more stable than carbocation (ii). This effec is also sometimes called as `beta-` or secondary isotope <a href="https://interviewquestions.tuteehub.com/tag/effect-966056" style="font-weight:bold;" target="_blank" title="Click to know more about EFFECT">EFFECT</a>.</body></html>