Q48E - Organic Chemistry (Mcmurry)

Question

Question: (R)-2-Bromooctane undergoes racemization to give ($\pm$)-2-bromooctane when treated with NaBr in dimethyl sulfoxide. Explain.

Step-by-Step Solution

Answer

Answer:

Step 1: S N 2 reaction

It is a nucleophilic substitution reaction in which an old bond is broken and a new bond has formed both processes occur simultaneously. Hence, it’s a single-step reaction.

The two reacting species are involved in the rate-determining steps.

Step 2: Definition of Nucleophiles and Stereochemistry

Nucleophiles are the negatively charged ions or the neutral species having the lone pair of electrons that are ready for bonding.

Stereochemistry - It is a study of the arrangement of atoms in a space that forms a molecule.

Step 3: Chemical reaction

When the 2 bromooctane react 50% then leads to the formation of 50% of R and 50% of S in the reaction. Thus, the reacting species is completely racemized.