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Karnataka Board PUCPUC Science 2nd PUC Class 12

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

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Questions

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

Chemical Equations/Structures
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Solution 1

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

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Solution 2

\[\ce{\underset{Ethanal}{2CH3CHO}->[dil.NaOH][Aldol condensation]\underset{Hydroxybutanal}{\overset{4}{C}H3 - \overset{3}{C}HOH - \overset{2}{C}H2 - \overset{1}{C}HO}->[H3O+/\Delta][-H2O]\underset{But-2-enal}{CH3 - CH = CH - CHO}}\]

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Chapter 8: Aldehydes, Ketones and Carboxylic Acids - Exercises [Page 256]

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NCERT Chemistry Part 1 and 2 [English] Class 12
Chapter 8 Aldehydes, Ketones and Carboxylic Acids
Exercises | Q 8.8 (ii) | Page 256

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