Question

The stability if `Me_2 C=CH_2` is more than that of `MeCH_2CH=CH_2` due to A. Inductive effect of `Me` group B. Resonance effect of `Me` group C. Hyperconjugative effect of `Me` group D. Resonance as well as inductive effect of `Me` group ?

Answer 1

`Me_2C=CH_2` is more stable than `MeCH_2CH=CH_2` because of the Hyperconjugation.

Explanation:

In `Me_2C=CH_2` with respect to Alkene the number of `alpha`-Hydrogen atoms are `6` (ie the number of hydrogen atoms taking part in hyperconjucation ).

While in `MeCH_2CH=CH_2` , the number of `alpha`-Hydrogen atoms are `2`.

So, the extent of hyperconjugation is more in `Me_2C=CH_2` than in `MeCH_2CH=CH_2`.

Thus, `Me_2C=CH_2` si more stable than `MeCH_2CH=CH_2`.

Hyperconjucation as explained in book by Paula Y. Bruice :-