Question

Methyl ester reacts with $EtMgBr$ to give $3^o$ alcohol (figure). The ester is:

• A. Methyl propanoate
• B. Methyl butanoate
• C. Methyl ethanoate
• D. Methyl formate

Answer 1

The correct option is B Methyl butanoate

The ester is Methyl butanoate. It reacts with 2 moles of ethyl magnesium bromide to form the tert alcohol.
$3^o$ alcohol is shown in the first figure, with two $\left(Et\right)$
Group obtained from G.R. Therefore, $(Pr-)$ group has come from the ester.
So, the ester is given in second figure (methyl butanoate). Hence, the answer is $\left(B\right)$.