Advertisements
Advertisements
Question
Convert the following:
Acetaldehyde to But-2-enal
Advertisements
Solution
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
RELATED QUESTIONS
How will you convert ethanal into the following compound?
Butane-1, 3-diol
Write chemical equations of the following reaction :
Propanone is treated with dilute Ba (OH)2-.
What is substituted imine called?
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.
Assertion: Aromatic aldehydes and formaldehyde undergo Cannizaro reaction.
Reason: Aromatic aldehydes are almost as reactive as formaldehyde.
Cross aldol condensation occurs between
Identify A and B from the following reaction:
\[\begin{array}{cc}
\ce{CH3}\phantom{.................}\\
|\phantom{....................}\\
\phantom{}\ce{2CH3 - C = O ->[Ba(OH)2] A ->[Δ] B + H2O}
\end{array}\]
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.
Which one of the following undergoes reaction with 50% sodiumhydroxide solution to give the corresponding alcohol and acid:
