Advertisements
Advertisements
प्रश्न
Which of the following compounds will undergo self-condensation in the presence of dilute NaOH solution?
विकल्प
C6H5CHO
CH3CH2CHO
(CH3)3C – CHO
H – CHO
Advertisements
उत्तर
CH3CH2CHO
Explanation:
Aldehydes and ketones having at least one α-hydrogen undergo a reaction in the presence of dilute alkali as catalyst to form β-hydroxy aldehydes (aldol) or β-hydroxy ketones (ketol), respectively. This is known as Aldol reaction.
Because of the presence of α-hydrogen, CH3CH2CHO undergoes an aldol reaction.
APPEARS IN
संबंधित प्रश्न
What is meant by the following term? Give an example of the reaction in the following case.
Aldol
How will you bring about the following conversion in not more than two steps?
Ethanol to 3-Hydroxybutanal
Cannizaro’s reaction is not given by ______.
Which product is formed when the compound 
is treated with concentrated aqueous \[\ce{KOH}\] solution?
Assertion: Aromatic aldehydes and formaldehyde undergo Cannizaro reaction.
Reason: Aromatic aldehydes are almost as reactive as formaldehyde.
Which of the following gives aldol con~ensation reaction?
Identify A and B from the following reaction:
\[\begin{array}{cc}
\ce{CH3}\phantom{.................}\\
|\phantom{....................}\\
\phantom{}\ce{2CH3 - C = O ->[Ba(OH)2] A ->[Δ] B + H2O}
\end{array}\]
Predict the reagent for carrying out the following transformations:
Ethanal to 3-hydroxy butanal
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?
