Organic Synthesis

Step 1: Hydrogenation of the alkene.
Hydrogenation of the alkene (C) using H and nickel (Ni) produces a saturated compound (A).

Step 2: Esterification.
The compound (A) is then treated with benzoic acid ( ) and water, resulting in esterification to give (B).

Step 3: Nucleophilic Substitution.
In the next step, the ester (B) undergoes nucleophilic substitution with ethanol ( ) to form (C).

Step 4: Grignard Reaction.
The compound (C) is then treated with ethylmagnesium bromide (EtMgBr) in anhydrous ether, followed by water work-up, resulting in the formation of 2-butanol as the final product (D).

Final Answer:

Step 1: Understanding the Reaction.
The reaction involves ozonolysis (using O₃), which cleaves alkenes into two carbonyl-containing compounds. The second step involves hydrogen peroxide (H₂O₂), which can lead to further oxidation or functional group transformations.

Step 2: Analyze the Reaction Mechanism.
- The initial compound undergoes ozonolysis, breaking it into two compounds. The cleavage of a C=C bond likely leads to propanoic acid (A), glutaric acid (B), and acetaldehyde (C).
- In the second step, hydrogen peroxide can oxidize any aldehyde groups to carboxylic acids, but here the aldehyde group remains as acetaldehyde.

Step 3: Conclusion.
Thus, the correct identification of the products is A = Propanoic Acid, B = Glutaric Acid, and C = Acetaldehyde. This corresponds to option (4).

Final Answer: