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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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