Question

Write hydrocarbon radicals that can be formed as intermediate during monochlorinated of $2$-methylpropane ? Which of them is more stable ? Give reasons .

Answer 1

$2$-methylpropane gives two types of radicals:
(1) $C{H}_3-CH\left(C{H}_3\right){-}^{\ast }C{H}_2$

(2) $C{H}_3{-}^{\ast }C\left(C{H}_3\right)-C{H}_3$

Tertiary $3^{\circ }$ free radical is more stable because it has $9\alpha$ Hydrogen and Due to hyperconjugation structure is stabilized. Primary $1^{\circ }$ free radical is less stable because of only $1\alpha$ hydrogen, and one hyper conjugative structure.

Hence (2) is more stable than (1)