Which of the following is least reactive in a nucleophilic substitution reaction?

Step-by-step solution

Chlorine of vinyl chloride ( CH ₂= . CHCl ) is non-reactive (less reactive) towards nucleophile in nucleophilic substitution reaction because it shows resonance due to + M effect of - Cl atom. In structure II, Cl-atom have positive charge and partial double bond character with C of vinyl group, so it is more tightly attracted towards the nucleus and it does not get replaced by nucleophile in S _ N reaction. Related Theory s p^3 -hybridized electrophile must have a leaving group ( X ) in order for the reaction to ta