Question

Which of the following compounds gives a secondary alcohol upon reaction with methylmagnesium bromide?

• A. Butyl formate
• B. 3-pentanone
• C. Pentanal
• D. Methyl butanoate

Hint:

Aldehydes react with Grignard reagents to form secondary alcohols, while ketones lead to tertiary alcohols.

Answer 1

The Correct Option is C

Methylmagnesium bromide \text{CH}_3\text{MgBr}
is a Grignard reagent. It adds to carbonyl groups, producing an alcohol. In this reaction, pentanal, an aldehyde, will react with methylmagnesium bromide to yield a secondary alcohol, whereas other reactants will not produce a secondary alcohol.