Question

What is a major product of the reaction in the box?​

Answer 1

Answer:

Molecule C

Explanation:

In this case, on the first reaction, we will have the production of a Grignard reagent. This molecule will react with $D_2O$ and a deuterium atom will be transferrred to the benzene ring. Then at the top of the molecule, we will have an acetal structure. This acetal can be broken by the action of the acid $DCl$, In the mechanism at the end, we will obtain a carbonyl group bonded to a hydrogen atom. Therefore we will have in the final product the aldehyde group. See figure 1 to further explanations.

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