Question

methyl chloride undergoes Sn2 reaction But Tertiary butyl chloride undergoes Sn1 Reaction why​

Answer 1

Answer:

Why does allyl chloride undergo SN1 reaction whereas n propyl chloride undergoes an SN2 reaction?

See first sn1 and sn2 is substitution and it's preferred nucleophilic substitution so ..

So you see that…

Sn1 mechanism involving In carbocation intermediate both allylic and benzylic halide having resonance so it's increase its stability of there carbocation.and speed up sn1 reaction..so

And sn2 reaction

The pi systems present in allylic and benzylic halides are able to overlap with the pi orbitals of the nucleophile and the leaving group in the 5-coordinate transition state of an SN2 reaction. This orbital overlap lowers the energy of the transition state

And some allyl halide is less sterically hindered than compare to alkyl halide ..

the carbons on the double bond of allyl and benzyl compounds are sp2 hybridized, and so are more electronegative than sp3 carbons. So the sp2 carbons pull alway some electron density from the alpha carbon

making it more electrophilic, and thus increasing SN2 reactivity…so it s hope help full