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कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

How will you convert ethanal into the following compound? But-2-enal - Chemistry

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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

रासायनिक समीकरण/संरचनाएँ
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उत्तर १

\[\ce{\underset{Ethanal}{2CH3CHO}->[(i) dil.NaOH][(ii) H+, \Delta]\underset{But-2-enal}{CH3CH = CHCHO}}\]

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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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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 8: Aldehydes, Ketones and Carboxylic Acids - Exercises [पृष्ठ २५६]

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एनसीईआरटी Chemistry Part 1 and 2 [English] Class 12
अध्याय 8 Aldehydes, Ketones and Carboxylic Acids
Exercises | Q 8.8 (ii) | पृष्ठ २५६

संबंधित प्रश्न

Write the products formed when CH3CHO reacts with the following reagents: CH3CHO in the presence of dilute NaOH


Describe the following:

Cross aldol condensation


Give reasons  Acetylation of aniline reduces its activation effect.


Write chemical equations of the following reaction : 

Propanone is treated with dilute Ba (OH)2-.


Write chemical equations of the following reaction :
Benzoyl chloride is hydrogenated in the presence of `"Pd"/(BaSO_4)`


What is substituted imine called?


Explain aldol condensation reaction in detail.


Cannizaro’s reaction is not given by ______.


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) \[\begin{array}{cc}
\phantom{}\ce{CH3}\\
|\phantom{...}\\
\ce{CH3 - C - CHO}\phantom{..}\\
|\phantom{...}\\
\phantom{}\ce{CH3}\\
\end{array}\]


Which of the following conversions can be carried out by Clemmensen Reduction?

(i) Benzaldehyde into benzyl alcohol

(ii) Cyclohexanone into cyclohexane

(iii) Benzoyl chloride into benzaldehyde

(iv) Benzophenone into diphenyl methane


Assertion: Aromatic aldehydes and formaldehyde undergo Cannizaro reaction.

Reason: Aromatic aldehydes are almost as reactive as formaldehyde.


When liquid ‘A’ is treated with a freshly prepared ammoniacal silver nitrate solution, it gives bright silver mirror. The liquid forms a white crystalline solid on treatment with sodium hydrogensulphite. Liquid ‘B’ also forms a white crystalline solid with sodium hydrogensulphite but it does not give test with ammoniacal silver nitrate. Which of the two liquids is aldehyde? Write the chemical equations of these reactions also.


Identify A and B from the following reaction:

\[\begin{array}{cc}
\ce{CH3}\phantom{.................}\\
|\phantom{....................}\\
\phantom{}\ce{2CH3 - C = O ->[Ba(OH)2] A ->[Δ] B + H2O}
\end{array}\]


Convert the following:

Acetaldehyde to But-2-enal


Predict the reagent for carrying out the following transformations:

Ethanal to 3-hydroxy butanal


Explain Aldol condensation of ethanal.


Which of the following does not give aldol condensation reaction?


Why is the α-hydrogens of aldehydes and ketones are acidic in nature?


When acetaldehyde is treated with dilute NaOH, the following reaction is observed.

\[\begin{array}{cc}
\ce{2CH3 - CHO ->[dil.NaOH] CH3 - CH - CH2 - CHO}\\
\phantom{...............}|\\
\phantom{.................}\ce{OH}
\end{array}\]

  1. What are the functional groups in the product?
  2. Can another product be formed during the same reaction? (Deduce the answer by doing atomic audit of reactant and product).
  3. Is this an addition reaction or condensation reaction?

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