The hyperconjugative stabilities of tertiary − butyl carbocation and but-2−ene, respectively, are due to

Question

The hyperconjugative stabilities of tertiary − butyl carbocation and but-2−ene, respectively, are due to (A) σ arrow p (empty) and σ arrow π * electron delocalisations. (B) σ arrow σ * and σ arrow π electron delocalisations. (C) σ arrow p (filled) and σ arrow π electron delocalisations. (D) p (filled) arrow σ * and σ arrow π * electron delocalisations.

Tardigrade Admin · Accepted Answer

Hyperconjugation effect is a permanent effect in which localization of σ electrons of C-H bond of an alkyl group directly attached to an atom of the unsaturated system or to an atom with an unshared p orbital takes place. It increases stability of carbocation, free radical and alkenes by decreasing energy.
Solution

C H_{3} - C H_{2} - C H = C H_{2} (σ - π *

electron

)

del ocalization.

Q. The hyperconjugative stabilities of tertiary − butyl carbocation and but-2−ene, respectively, are due to

$σ \to p$ (empty) and $σ \to π *$ electron delocalisations.

$σ \to σ *$ and $σ \to π$ electron delocalisations.

$σ \to p$ (filled) and $σ \to π$ electron delocalisations.

$p$ (filled) $\to σ $ and $σ \to π $ electron delocalisations.

Q. The hyperconjugative stabilities of tertiary − butyl carbocation and but-2−ene, respectively, are due to

σ→p (empty) and σ→π∗ electron delocalisations.

σ→σ∗ and σ→π electron delocalisations.

σ→p (filled) and σ→π electron delocalisations.

p (filled) →σ∗ and σ→π∗ electron delocalisations.

$σ \to p$ (empty) and $σ \to π *$ electron delocalisations.

$σ \to σ *$ and $σ \to π$ electron delocalisations.

$σ \to p$ (filled) and $σ \to π$ electron delocalisations.

$p$ (filled) $\to σ $ and $σ \to π $ electron delocalisations.