What is the major product of the following reaction?

Question

Quizplus · Accepted Answer

The reaction involves substitution of the chloro group by the iodide ion. This is a nucleophilic substitution reaction, SN2 mechanism. Thus, the incoming nucleophile (iodide ion) attacks the carbon atom bearing the leaving group (chloro group) from the opposite side, leading to inversion of configuration of the stereocenter. The major product will be the product that forms with the stereochemistry inverted at the stereocenter, which is option A (1-iodobutane). The other options are either the starting material or minor products that may form due to a mixture of SN2 and SN1 mechanisms or due to the formation of carbocation intermediate in the SN1 reaction.

What Is the Major Product of the Following Reaction