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Karnataka Board PUCPUC Science 2nd PUC Class 12

Which of the following compounds do not undergo aldol condensation?

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Question

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

Short/Brief Note
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Solution

(ii)

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

Explanation:

In these compounds, a-hydrogen is absent. So, aldol condensation does not take place in these compounds.

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Chapter 12: Aldehydes, Ketones and Carboxylic Acids - Multiple Choice Questions (Type - I) [Page 171]

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NCERT Exemplar Chemistry Exemplar [English] Class 12
Chapter 12 Aldehydes, Ketones and Carboxylic Acids
Multiple Choice Questions (Type - I) | Q 13 | Page 171

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