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प्रश्न
How will you convert ethanal into the following compound?
But-2-enal
Carry out the following conversion:
Ethanal to But-2-enal
How will you bring about the following conversion?
Ethanal to but-2-enal
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उत्तर १
\[\ce{\underset{Ethanal}{2CH3CHO}->[(i) dil.NaOH][(ii) H+, \Delta]\underset{But-2-enal}{CH3CH = CHCHO}}\]
उत्तर २
\[\ce{\underset{Ethanal}{2CH3CHO}->[dil.NaOH][Aldol condensation]\underset{Hydroxybutanal}{\overset{4}{C}H3 - \overset{3}{C}HOH - \overset{2}{C}H2 - \overset{1}{C}HO}->[H3O+/\Delta][-H2O]\underset{But-2-enal}{CH3 - CH = CH - CHO}}\]
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संबंधित प्रश्न
Which of the following compounds would undergo aldol condensation, which the Cannizzaro reaction and which neither? Write the structures of the expected products of aldol condensation and Cannizzaro reaction.
- Methanal
- 2-Methylpentanal
- Benzaldehyde
- Benzophenone
- Cyclohexanone
- 1-Phenylpropanone
- Phenylacetaldehyde
- Butan-1-ol
- 2, 2-Dimethylbutanal
How will you bring about the following conversion in not more than two steps?
Ethanol to 3-Hydroxybutanal
How will you bring about the following conversion in not more than two steps?
Benzaldehyde to 3-Phenylpropan-1-ol
Complete the synthesis by giving missing starting material, reagent or product.
\[\begin{array}{cc}
\ce{C6H5CHO}\phantom{............}\\
\phantom{........}\ce{+\phantom{......}\ce{->[dil.NaOH][\Delta]}}\phantom{...}\\
\ce{CH3CH2CHO}\phantom{............}
\end{array}\]
Give reasons Acetylation of aniline reduces its activation effect.
Write a chemical equation for the following reaction:
Propanone is treated with dilute Ba( OH)2.
What is substituted imine called?
Which product is formed when the compound 
is treated with concentrated aqueous \[\ce{KOH}\] solution?
Which of the following compounds do not undergo aldol condensation?
(i) \[\ce{CH3 - CHO}\]
(ii) 
(iii) \[\begin{array}{cc}
\phantom{}\ce{O}\\
\phantom{}||\\
\ce{CH3 - C - CH3}
\end{array}\]
(iv) \[\begin{array}{cc}
\phantom{}\ce{CH3}\\
|\phantom{...}\\
\ce{CH3 - C - CHO}\phantom{..}\\
|\phantom{...}\\
\phantom{}\ce{CH3}\\
\end{array}\]
Why are carboxylic acids more acidic than alcohols or phenols although all of them have hydrogen atom attached to a oxygen atom \[\ce{(-O-H)}\]?
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?
Convert the following:
Acetaldehyde to But-2-enal
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:
Which of the following does not give aldol condensation reaction?
Why is the α-hydrogens of aldehydes and ketones are acidic in nature?
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?
