Question

For the following reaction, the cyanide nucleophile could reasonably substitute at either of two positions. One mechanism produces 4-cyanoheptane and dimethylsulfide. The competing mechanism produces 4-methylthioheptane and acetonitrile (CH3CN). In practice, only one substitution is observed. Choose the most likely mechanistic pathway for this reaction and draw both of the products. Select whether it proceeds via an SN1 or SN2 mechanism.

This is a Mixed question/ It is worth 4 points / You have unlimited attempts / There is a 5% attempt penalty 20 Question (4 points) See page 447 For the following reaction, the cyanide nucleophile could reasonably substitute at either of two positions. One mechanism produces 4-cyanoheptane and dimethylsulfide. The competing mechanism produces 4-methylthioheptane and acetonitrile (CH3CN). In practice, only one substitution is observed. Choose the most likely mechanistic pathway for this reaction and draw both of the products. Select whether it proceeds via an S1 or S2 mechanism NOCN 14th attempt

Answer 1

Overall reaction is SN2 since for sn2 reaction order : 1°>2°>3°

Hence methyl Caynide is favoured than 4-caynooctane. Since it is formed from 2° alkyl halide.(steric crowd)

While methyl Caynide formed from methyl halide ,no steric crowd.

SN2 No-07 a {dos-