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Assertion : 2,3-dimethyl but-2-ene is mo...

Assertion `:` `2,3-`dimethyl but`-2-`ene is more stable than but`-2-`ene.
Reason `:` `2,3-`dimethyl but`-2-` ene possesses `12 alpha-` hydrogen atoms whereas but `-2-`ene possesses only `6 alph-`hydrogen atms and therefore former shows more pronounced hyperconjugation.

A

If both assertion and reason are true and the reason is the correct explanation of the assertion.

B

If both assertion and reason are true but reason is not the correct explanation of the assertion.

C

If assertion is true but reason is false.

D

If assertion is false but reason is true.

Text Solution

Verified by Experts

The correct Answer is:
A

The phenomenon of displacement of electrons by conjugative mechanism involving `sigma -` and `pi-` electron is called hyperconjugation. It happens when alkyl groups having at least one of the `alpha-`carbon atoms attached to an unsaturated carbon atom is able to release electron due to delocalization of `sigma-` and `pi-` bond. It is more pronounced as `alph-H` atoms are more in number . Thus, stability of alkenes has been explained in terms of hyperconjugation.
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