Question – (3) – Which is the correct
order of stability of free radicals among the following options –
Answer with explanation –
The correct order of stability of the free radicals is –
The
carbon atom in a free radical has only seven electrons around it. This means
that its octet is not completed. Therefore, this carbon atom is electron
deficient. The + I effect of alkyl group tends to increase its electron density.
This means that, more the alkyl groups attached to the carbon atom of free
radical, the greater its stability.
The
relative stabilities of the common free radicals is as follow –
Benzyl
> Allyl > Tertiary > Secondary > Primary > Methyl > Vinyl
Here,
the Benzyl and allyl radicals are more stable because of the resonance effect.