Question

Suggest a suitable reagent to prepare secondary alcohol with the identical group using a Grignard reagent.

Answer 1

Acetaldehyde reacts with Grignard reagent to give an addition product, which further undergoes acid hydrolysis to yield secondary alcohol, that is isopropyl alcohol.

\[\begin{array}{cc}
\phantom{..}\ce{O}\phantom{........................................}\ce{OMgBr}\phantom{................................}\\
\phantom{.}||\phantom{.........................................}|\phantom{.....................................}\\
\ce{\underset{(Acetaldehyde)}{CH3 - C - H} + \underset{(Methyl magnesium bromide)}{CH3 - Mg - Br} -> CH3 - C - H ->[H^+/H2O] CH3 - CH - OH + MgBr(OH)}\\
\phantom{............................}|\phantom{.....................}|\phantom{.}\\
\phantom{...................................}\ce{CH3}\phantom{.............}\ce{\underset{(isopropyl alcohol)}{CH3}}\phantom{}
\end{array}\]