Organic Chemistry> Why is a 3 degree carbocation more stable...

Why is a 3 degree carbocation more stable than a 2 or 1 degree carbocation?
And why is a 1 degree carbanion more stable than a 2 or 3 degree carbanion?

Satviki Pathak , 10 Years ago

Grade 11

3 Answers

Gaurav

Last Activity: 10 Years ago

Hello Student
3 degree carbocation more stable than a 2 or 1 degree carbocation due to the fact that in case of 3 degree carbocation there are three methyl group which increase the stability of carbocation due to its electron donating nature. In care of two degree carbocation there are two methyl groups while in case of primary carbocation there is only one methyl group.

But in case of anions the effect is inverse because the electron donating nature of methyl group decreases the stability of anion.

Kushagra Madhukar

Last Activity: 5 Years ago

Dear student,

Please find the answer to your question.

3 degree carbocation more stable than a 2 or 1 degree carbocation due to the fact that in case of 3 degree carbocation there are three methyl group which increase the stability of carbocation due to its electron donating nature. In care of two degree carbocation there are two methyl groups while in case of primary carbocation there is only one methyl group.

But in case of anions the effect is inverse because the electron donating nature of methyl group decreases the stability of anion.

Thanks and regards,

Kushagra

Srinivasan S

Last Activity: 5 Years ago

Any charged species, carbocation or carbanion, can be stable to the extent in which the charge is delocalized over full molecule.

For a carbocation, the delocalization occurs due to both +I effect of alkyl groups as also hyperconjugation, which is higher in order tert > sec > primary. so the order of stabiity is also same, tert > sec > primary carbocation.

In a carbanion, with added alkyl groups attached to the charged C, which are all +I donating, there is increased concentration of charge & no delocalization. This makes stability of tert