Advertisements
Advertisements
प्रश्न
Convert the following:
Acetaldehyde to But-2-enal
Advertisements
उत्तर
Aldol condensation (in presence of dil. \[\ce{NaOH}\]) followed by dehydration.
\[\begin{array}{cc}
\phantom{}\ce{\underset{Acetaldehyde}{CH3CHO} ->[dil. NaOH] CH3 - CH - CH2 - CHO ->[Δ][-H2O] \underset{\underset{(Adol condensation product)}{But-2-enal}}{CH3 - CH} = CH - CHO}\\
|\phantom{.........................}\\
\ce{\underset{\underset{(Adol)}{3-Hydroxybutanal}}{OH}}\phantom{.......................}\\
\end{array}\]
APPEARS IN
संबंधित प्रश्न
How will you bring about the following conversion in not more than two steps?
Ethanol to 3-Hydroxybutanal
Describe the following:
Cross aldol condensation
Write a chemical equation for the following reaction:
Propanone is treated with dilute Ba( OH)2.
Which product is formed when the compound 
is treated with concentrated aqueous \[\ce{KOH}\] solution?
Assertion: The α-hydrogen atom in carbonyl compounds is less acidic.
Reason: The anion formed after the loss of α-hydrogen atom is resonance stabilised.
Which of the following gives aldol con~ensation reaction?
\[\ce{CH3-CH2-CHO ->[dil][alkali] Product}\]
The product in the above reaction is:
Assertion (A): The final product in Aldol condensation is always α, β-unsaturated carbonyl compound.
Reason (R): α, β-unsaturated carbonyl compounds are stabilised due to conjugation.
When acetaldehyde is treated with dilute NaOH, the following reaction is observed.
\[\begin{array}{cc}
\ce{2CH3 - CHO ->[dil.NaOH] CH3 - CH - CH2 - CHO}\\
\phantom{...............}|\\
\phantom{.................}\ce{OH}
\end{array}\]
- What are the functional groups in the product?
- Can another product be formed during the same reaction? (Deduce the answer by doing atomic audit of reactant and product).
- Is this an addition reaction or condensation reaction?
What is aldol condensation? Explain it with suitable examples.
