Identify the correct order of reactivity of the following compounds towards the S _ N 1 reaction. (I) (II) (III)

Step-by-step solution

The reactivity of alkyl halides towards the S _ N 1 reaction depends on the stability of the carbocation intermediate formed after the departure of the leaving group (chloride ion). The carbocations formed from the given compounds are: (I) Cyclopropylmethyl cation (II) Tricyclopropylmethyl cation (III) Dicyclopropylmethyl cation The cyclopropylmethyl cation is exceptionally stable due to the delocalization of the -electrons of the bent bonds (banana bonds) of the cyclopropyl ring into the vacant p-orbital of the ad