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प्रश्न
Convert the following:
Acetaldehyde to But-2-enal
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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
Write structural formulas and names of four possible aldol condensation products from propanal and butanal. In each case, indicate which aldehyde acts as nucleophile and which as electrophile.
Compounds A and C in the following reaction are:
\[\ce{CH3CHO ->[(i) CH3MgBr][(ii) H2O] (A) ->[H2SO4, Δ] (B) ->[Hydroboration oxidation] (C)}\]
Compound ‘A’ was prepared by oxidation of compound ‘B’ with alkaline \[\ce{KMnO4}\]. Compound ‘A’ on reduction with lithium aluminium hydride gets converted back to compound ‘B’. When compound ‘A’ is heated with compound B in the presence of \[\ce{H2SO4}\] it produces fruity smell of compound C to which family the compounds ‘A’, ‘B’ and ‘C’ belong to?
Why are carboxylic acids more acidic than alcohols or phenols although all of them have hydrogen atom attached to a oxygen atom \[\ce{(-O-H)}\]?
Which of the following gives aldol con~ensation reaction?
Predict the reagent for carrying out the following transformations:
Ethanal to 3-hydroxy butanal
\[\ce{CH3-CH2-CHO ->[dil][alkali] Product}\]
The product in the above reaction is:
The major product of the following reaction is:

Explain the aldol condensation of ethanal.
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.
