Final answer:
Grignard reagents can add to aldehydes, ketones, and esters. These reactions occur due to the carbonyl group in these compounds being susceptible to nucleophilic attack from Grignard reagents, ultimately forming alcohols.
Step-by-step explanation:
Grignard reagents are highly reactive organometallic compounds that can react through nucleophilic addition with several functional groups containing a carbonyl group. Specifically, Grignard reagents can add to aldehydes, ketones, and esters. The reactivity towards these functional groups arises from the polar carbon-oxygen double bond present in each of these compounds.
In aldehydes and ketones, the carbonyl carbon is partial positive which makes it susceptible to nucleophilic attack by the Grignard reagent, leading to the formation of an alcohol upon subsequent work-up. Although esters also contain a carbonyl group, the reaction with Grignard reagents proceeds differently compared to aldehydes and ketones, involving two equivalents of the reagent and leading ultimately to a tertiary alcohol after a series of steps.