Question

The order of stability of the carbon radicals $3^{\circ },2^{\circ },1^{\circ }$ and $\dot{C}{H}_3$ is:

• A. $1^{\circ }>2^{\circ }>3^{\circ }>\dot{C}{H}_3$
• B. $\dot{C}{H}_3>1^{\circ }>2^{\circ }>3^{\circ }$
• C. $3^{\circ }>2^{\circ }>1^{\circ }>\dot{C}{H}_3$
• D. $\dot{C}{H}_3>3^{\circ }>2^{\circ }>1^{\circ }$

Answer 1

The correct option is C $3^{\circ }>2^{\circ }>1^{\circ }>\dot{C}{H}_3$

Increasing the number of alkyl groups on the carbon bearing the free radical increases its stability due to electron releasing $+I$ effect of alkyl group. Radical stability increases in the order methyl < primary < secondary < tertiary.