Draw structures for A-D for each of the following: b.

Verified step by step guidance

1. Identify the starting material as a carboxylic acid.
2. React the carboxylic acid with LiAlH4 followed by H2O to reduce it to the corresponding primary alcohol (Compound i).
3. Convert the primary alcohol (Compound i) to the corresponding acid chloride (Compound ii) using SOCl2 in the presence of pyridine.
4. React the acid chloride (Compound ii) with triphenylphosphine (P(C6H5)3) and butyllithium (C4H9Li) to form the corresponding ketone (Compound iii).
5. Identify Compound iv as the starting material, which is a ketone, and recognize that it is the same as Compound iii.

Key Concepts

Reduction Reactions

Reduction reactions involve the gain of electrons or the decrease in oxidation state by a molecule. In organic chemistry, this often refers to the conversion of carbonyl compounds (like aldehydes and ketones) to alcohols. The reaction shown in the image uses lithium aluminum hydride (LiAlH4), a strong reducing agent, to reduce a carboxylic acid to an alcohol, which is a key step in synthesizing various organic compounds.

Formation of Acid Chlorides

Acid chlorides are derived from carboxylic acids by replacing the hydroxyl (-OH) group with a chlorine atom. This transformation is typically achieved using reagents like thionyl chloride (SOCl2) in the presence of a base such as pyridine. Acid chlorides are highly reactive intermediates in organic synthesis, allowing for further transformations into other functional groups, as illustrated in the reaction scheme.

Grignard Reagents

Grignard reagents are organomagnesium compounds that are highly reactive and used to form carbon-carbon bonds in organic synthesis. They are generated by reacting alkyl or aryl halides with magnesium metal. In the reaction scheme, the Grignard reagent (C4H9Li) reacts with an electrophile to form a new carbon-carbon bond, demonstrating their utility in building complex organic molecules.