Question

Which of the following reactions can be used to prepare above given product ?

• A.
• B.
• C.
• D.

Answer 1

The correct option is B

Grignard reagent is a strong nucleophile. It undergoes nucleophilic addition reaction when it reacts with aldehyde, ester and ketone.
Grignard reagent react with formaldehyde to form $1^{\circ }$ alcohol.
Grignard reagent react with aldehyde except formaldehyde to form $2^{\circ }$ alcohol.
Grignard reagent react with ketone to form $3^{\circ }$ alcohol.
The given compound is tertiary $\left(3^{\circ }\right)$ alcohol with one methyl and 2 ethyl group so to prepare it we need ketone and grignard reagent which is in option (a) and (b) but to get the 2 ethyl group and one methyl group reaction (b) is suitable. Hence correct option is (b).
The reaction is as follow: