Chemistry Carbocations Stability: Compare 2 & 3 for Electron Induction

[duchuy]

Homework Statement

Which carbocation is more stable

Relevant Equations

Inductive effect

Hi,
I have to determine which molecule ( 2 and 3) is more stable.
I tried to determine the stability using the inductive effect, but when I tried to that, I ended with molecule 2 being more stable than molecule 3 since:
x3 ch3 will push electrons towards c+
Whilst in the 2nd molecule the is a H, which have no inductive effect on C+ therefore it's more stable which is incorrect.
Please tell me where I misunderstood the problem thank you!
The molecules are attached to this thread.

 

[Mayhem]

Generally, tertiary carbocations are more stable than secondary carbocations. So you're definitely right that compound 2 being more stable is incorrect. Carbon is electron donating compared to hydrogen. So a carbocation placed next to three carbon atoms will be more stable than one placed next to two carbon atoms and one hydrogen with that reasoning.

 

[duchuy]

Generally, tertiary carbocations are more stable than secondary carbocations. So you're definitely right that compound 2 being more stable is incorrect. Carbon is electron donating compared to hydrogen. So a carbocation placed next to three carbon atoms will be more stable than one placed next to two carbon atoms and one hydrogen with that reasoning.

Thank you for your reply sir!