Question

Which one of the following would undergo faster SN2 reaction? Explain

CH3 – CH = CH – Cl or CH3CH2CH2 – Cl

Answer 1

In vinyl chloride (CH3-CH=CH-Cl) lone pair of chlorine is in resonance so chlorine will not get removed easily while in case of alkyl chloride resonance is not present.There's no such resonance in propylchloride. Hence, chlorine reacts readily with the nucleophile. CH3-CH2-CH2-Cl is more reactive in sn2 reactions.