NTA Abhyas JEE Main2020ChemistryGeneral Organic ChemistryPractice
The hyperconjugative stabilities of tertiary − butyl carbocation and but-2−ene, respectively, are due to
Options
- Aσ → p (empty) and σ → π * electron delocalisations.
- Bσ → σ * and σ → π electron delocalisations.
- Cσ → p (filled) and σ → π electron delocalisations.
- Dp (filled) → σ * and σ → π * electron delocalisations.
Correct answer
A. σ → p (empty) and σ → π * electron delocalisations.
Step-by-step solution
Hyperconjugation involves delocalisation of σ electron of α C-H with π empty p-orbital. It increases stability of carbocation, free radical and alkenes by decreasing energy. C H 3 - CH = C H 2 σ - π * e l e c t r o n delocalization