Question

Rank decreasing order of stability of free radicals formed by the breaking of the bonds indicated with the arrows.

• A. c > a > b
• B. a > b > c
• C. b > a > c
• D. b > c > a

Answer 1

The correct option is C b > a > c

Free radical stability $\propto$ Number of $\alpha$-H


The free radical formed by breaking of bond a has 4 $\alpha$-H, b has 7 $\alpha$-H, and c has only 1 $\alpha$-H. Therefore, the stability order of free radicals formed is:
b > a > c