Question

The product formed in Aldol condensation is

• A. an alpha beta unsaturated ester
• B. a beta hydroxy acid
• C. A beta hydroxy aldehyde or a beta hydroxy ketone
• D. an alpha hydroxy aldehyde or ketone

Answer 1

The Correct Option is C

Aldol condensation is a reaction between two carbonyl compounds, typically an aldehyde and/or a ketone, in the presence of a base. It involves the formation of a β-hydroxy aldehyde or a β-hydroxy ketone initially, which can further undergo dehydration to form an α,β-unsaturated aldehyde or ketone.

Let's break down the process:

1. In an aldol condensation reaction, a base (such as hydroxide ion, \text{OH}^-\) is used to deprotonate the α-hydrogen of an aldehyde or ketone to generate a carbanion (enolate ion).
2. This enolate ion acts as a nucleophile and attacks the carbonyl carbon of another molecule of aldehyde or ketone, forming a β-hydroxy aldehyde or ketone.
3. The general reaction for an aldol condensation between two aldehyde molecules can be illustrated as follows:

\begin{align*} \text{RCHO} + \text{CH}_2\text{COR}' & \xrightarrow{\text{Base}} \text{RCH(OH)CH}_2\text{COR}' \end{align*}

Here, the product \text{RCH(OH)CH}_2\text{COR}' is a β-hydroxy aldehyde if the starting materials are aldehydes, or a β-hydroxy ketone if they are ketones.

This addition is followed by dehydration under certain conditions to form an α,β-unsaturated carbonyl compound, but the question specifically asks for the product "formed in Aldol condensation," which is the initial product, i.e., β-hydroxy aldehyde or β-hydroxy ketone.

Hence, the correct answer is: A β-hydroxy aldehyde or a β-hydroxy ketone.