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Question
Describe the following:
Cross aldol condensation
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Solution
When aldol condensation is carried out between two different aldehydes and/or ketones, it is called cross aldol condensation. If both of them contain a-hydrogen atoms, it gives a mixture of four products. This is illustrated below by the aldol reaction of a mixture of ethanal and propanal.
Ketones can also be used as one component in the cross-aldol reactions.
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RELATED QUESTIONS
What is meant by the following term? Give an example of the reaction in the following case.
Aldol
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(i) \[\ce{CH3 - CHO}\]
(ii) 
(iii) \[\begin{array}{cc}
\phantom{}\ce{O}\\
\phantom{}||\\
\ce{CH3 - C - CH3}
\end{array}\]
(iv) \[\begin{array}{cc}
\phantom{}\ce{CH3}\\
|\phantom{...}\\
\ce{CH3 - C - CHO}\phantom{..}\\
|\phantom{...}\\
\phantom{}\ce{CH3}\\
\end{array}\]
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\[\begin{array}{cc}
\ce{2CH3 - CHO ->[dil.NaOH] CH3 - CH - CH2 - CHO}\\
\phantom{...............}|\\
\phantom{.................}\ce{OH}
\end{array}\]
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