Methyl group attached to a positively charged carbon atom stabilizes the carbocation due to

Question

Professor PC Thomas Classes · Answer

(c) : Alkyl groups directly attached to the positively charged carbon stabilise the carbocations due to hyperconjugation effect. Example : $\mathrm{CH}_3 \mathrm{CH}_2^{+}$(ethyl cation) in which the positively charged carbon atom has an empty $p$-orbital. One of the $\mathrm{C}-\mathrm{H}$ bonds of the methyl group can align in the plane of this empty $p$-orbital and the electrons constituting the $\mathrm{C}-\mathrm{H}$ bond in plane with this $p$-orbital can then be delocalised into the empty p-orbital. \  This type of overlap stabilises the carbocation because electron density from the adjacent $\sigma$ bond helps in dispersing the positive charge.