What is the actual reason why the hydrogen adds to the carbon withthe most hydro
ID: 687309 • Letter: W
Question
What is the actual reason why the hydrogen adds to the carbon withthe most hydrogens? I heard something about that this makes themost stable carbocation or something is this true???Explanation / Answer
Yes this is true. By adding to H to the carbon with the mosthydrogens, you form a more substituted carbocation. Carbocationstability increases with degrees of substitution. The stabilitytrend is tertiary>secondary>primary>methyl. This is due toan effect called hyperconjugation (partial dissipation of thepositive charge through the sigma bond framework). Also if anyresonance stabilization (allylic or benzyllic) could be achievedfrom one of the positions, the hydrogen will add often add in sucha way to form a carbocation at the resonance stabilizedposition.