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Question
Write a chemical equation for the following reaction:
Propanone is treated with dilute Ba( OH)2.
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Solution
This is a self-aldol condensation reaction.
\[\begin{array}{cc}
\phantom{............}\ce{CH3} \phantom{........................}\ce{CH3}\phantom{}\\
\phantom{..........................}|\phantom{............................}|\phantom{.................}\\
\ce{\underset{\text{Acetone or propanone}}{2CH3COCH3}<-->[Dil. Ba(OH)2] CH3-C-CH2-CO-CH3->[ ][\Delta]CH3-\underset{\text{4-methyl pent-3-en-2-one}}{C=CH-CO-CH3 }+ H2O}\\
\phantom{..................................}|\phantom{........................} \text{(Aldol condensation product)}\phantom{..}\\
\ce{\underset{\text{4-Hydroxy-4-methyl pentan-2-one(ketol)}}{OH}}\phantom{...................}\\
\end{array}\]
RELATED QUESTIONS
Write the products formed when CH3CHO reacts with the following reagents: CH3CHO in the presence of dilute NaOH
How will you convert ethanal into the following compound?
But-2-enal
Describe the following:
Cross aldol condensation
Complete the synthesis by giving missing starting material, reagent or product.
\[\begin{array}{cc}
\ce{C6H5CHO}\phantom{............}\\
\phantom{........}\ce{+\phantom{......}\ce{->[dil.NaOH][\Delta]}}\phantom{...}\\
\ce{CH3CH2CHO}\phantom{............}
\end{array}\]
Why is alpha (α) hydrogen of carbonyl compounds acidic in nature?
What is substituted imine called?
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) \[\begin{array}{cc}
\phantom{}\ce{CH3}\\
|\phantom{...}\\
\ce{CH3 - C - CHO}\phantom{..}\\
|\phantom{...}\\
\phantom{}\ce{CH3}\\
\end{array}\]
Give reasons to support the answer:
Presence of Alpha hydrogen in aldehydes and ketones is essential for aldol condensation.
The major product of the following reaction is:

Explain Aldol condensation of ethanal.
