Suggest the appropriate reagents to carry out the following transformations.
(d)

Verified step by step guidance

1. Identify the functional group transformation: The starting material is an alcohol, and the product is an alkyl bromide. This indicates a substitution reaction where the hydroxyl group (-OH) is replaced by a bromine atom (Br).
2. Consider the stereochemistry: The starting alcohol has a specific stereochemistry, and the product is racemic, indicating that the reaction proceeds with loss of stereochemistry, likely through a carbocation intermediate.
3. Select a reagent that can convert an alcohol to an alkyl bromide: A common reagent for this transformation is phosphorus tribromide (PBr₃), which can convert alcohols to alkyl bromides with inversion of configuration. However, since the product is racemic, a different approach is needed.
4. Choose a reagent that forms a carbocation intermediate: Using hydrobromic acid (HBr) in the presence of heat can lead to the formation of a carbocation intermediate, allowing for the racemization of the stereocenter.
5. Verify the mechanism: The alcohol reacts with HBr, forming a carbocation after the loss of water. The carbocation can then be attacked by bromide ion, leading to the formation of the racemic alkyl bromide product.

Key Concepts

Reagents in Organic Reactions

Reagents are substances that are added to a chemical reaction to cause a transformation. In organic chemistry, selecting the appropriate reagents is crucial for achieving the desired product. Different reagents can facilitate various types of reactions, such as oxidation, reduction, substitution, or elimination, and understanding their roles helps predict the outcome of the reaction.

Functional Groups

Functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. Recognizing functional groups is essential for predicting how a compound will react with different reagents. For example, alcohols, carboxylic acids, and amines each have distinct reactivity patterns that guide the choice of reagents for transformations.

Reaction Mechanisms

A reaction mechanism is a step-by-step description of how a chemical reaction occurs at the molecular level. Understanding mechanisms helps chemists predict the products of reactions and the conditions required for them. Familiarity with common mechanisms, such as nucleophilic substitution or electrophilic addition, is vital for selecting the right reagents and conditions for a given transformation.