a. Show the reagents required to form the primary alcohol in each of the following reactions.

Verified step by step guidance

1. Identify the target compound: The primary alcohol (RCH2OH) is the desired product in each reaction. The goal is to determine the reagents required to convert the given starting materials into this alcohol.
2. For aldehydes (RCHO): Use a reducing agent such as sodium borohydride (NaBH4) or lithium aluminum hydride (LiAlH4) to reduce the aldehyde to a primary alcohol. The reaction involves the addition of hydrogen to the carbonyl group.
3. For carboxylic acids (RCOOH): Use a strong reducing agent like lithium aluminum hydride (LiAlH4) to reduce the carboxylic acid to a primary alcohol. Note that NaBH4 is not effective for carboxylic acids.
4. For esters (RCOOR'): Use lithium aluminum hydride (LiAlH4) to reduce the ester to a primary alcohol. The reaction involves breaking the ester bond and forming the alcohol.
5. For alkyl halides (RCH2Br): Use a nucleophilic substitution reaction with hydroxide ions (OH-) or water (H2O) to replace the halide group with a hydroxyl group, forming the primary alcohol.

Key Concepts

Reagents for Alcohol Formation

To synthesize primary alcohols, specific reagents are required depending on the starting materials. Common reagents include reducing agents like lithium aluminum hydride (LiAlH4) or sodium borohydride (NaBH4) for reducing carbonyl compounds, and halogenated compounds can be converted to alcohols through nucleophilic substitution reactions.

Nucleophilic Substitution Reactions

Nucleophilic substitution is a fundamental reaction in organic chemistry where a nucleophile replaces a leaving group in a molecule. This process is crucial for converting alkyl halides or other electrophiles into alcohols, as the nucleophile (often hydroxide ion, OH-) attacks the carbon atom bonded to the leaving group, resulting in the formation of an alcohol.

Reduction of Carbonyl Compounds

The reduction of carbonyl compounds (aldehydes and ketones) to primary alcohols is a key transformation in organic synthesis. This process involves the addition of hydrogen or hydride ions to the carbonyl carbon, effectively converting the carbonyl group (C=O) into a hydroxyl group (C-OH), thus forming an alcohol. Common reducing agents include NaBH4 and LiAlH4.