Question

Consider the following aldol condensation reaction $C{H}_{3}CHO\underset{\Delta }{\overset{\left(i\right)Dil.NaOH,5^{o}C}{\to }}C{H}_{3}CH=CHCHO$
The nucleophile is:

• A. $\stackrel{-}{C}{H}_{2}CHO$
• B. $C{H}_2=CH{O}^{-}$
• C. $C{H}_2=CHOH$
• D. None of the above

Answer 1

The correct option is A $\stackrel{-}{C}{H}_{2}CHO$

Aldol condensation occurs in aldehydes having α-hydrogen with a dilute base to give β-hydroxy aldehydes called aldols. This reaction is most commonly known as aldol condensation. If the condensation reaction occurs between two different carbonyl compounds it is called crossed aldol condensation.

Aldol Condensation can be defined as an organic reaction in which enolate ion reacts with a carbonyl compound to form β-hydroxy ketone or β-hydroxy aldehyde, followed by dehydration to give a conjugated enone. Aldol Condensation plays a vital role in organic synthesis, creating a path to form carbon-carbon bonds.

General reaction of aldol condensation is as follows:
Mechanism involves 4 steps:
1) Enolate formation

2) Addition of the enolate

3) Formation of an aldol
4) Condensation
Hence, the correct answer is option (a).