The correct order of increasing reactivity of C- X bond towards nucleophile in the following compounds is

Question

The correct order of increasing reactivity of C- X bond towards nucleophile in the following compounds is (A) I < II < IV < III (B) II < III < I < IV (C) IV < III < I < II (D) III < II < I < IV

Tardigrade Admin · Accepted Answer

Alkyl halides are more reactive towards nucleophilic substitution. Reactivity depends upon the stability of carbocation intermediate formed.
Among the given halides, aryl halide (

C_{6} H_{5} X

) is least reactive towards nucleophile due to the possible four reason
(i) Reasonance effect
(ii) Hybridisation
(iii) Unstability of phenyl cation
(iv) Double bond character

C - X

bond acquire some double bond character due to resonance. Presence of electron withdrawing groups like -

N O_{2}

at ortho and para-positions facilitate the nucleophilic displacement of

- X

of aryl halide. Among alkyl halides,

3^{\circ}

halides are more reactive as compared to

2^{\circ}

halides due to the formation of more stable carbocation. Hence, the order of reactivity of

C - X

bond towards nucleophile is as

Q. The correct order of increasing reactivity of C−X bond towards nucleophile in the following compounds is

I < II < IV < III

II < III < I < IV

IV < III < I < II

III < II < I < IV

Q. The correct order of increasing reactivity of $C - X$ bond towards nucleophile in the following compounds is