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Aldehydes and ketones react reversibly with two equivalents of alcohol in the presence of an acid catalyst to give acetals. Alcohols are poor nucleophiles, and so protonation of the carbonyl oxygen is used to make the carbonyl carbon a stronger electrophile. Addition of the first equivalent of alcohol gives a hemiacetal, a hydroxyether. Addition of the second equivalent of alcohol is accompanied by loss of water to yield the product acetal. Draw curved arrows to show the movement of electrons in this step of the mechanism.

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Answer:

Aldehyde and ketone both react with alcohols (2 equivalent) in the presence of acid catalyst to give acetals.

Step-by-step explanation:

Alcohols are poor nucleophiles and so protonation of the carbonyl oxygen used to make the carbonyl carbon a stronger electrophile. Addition of the first equivalent of alcohols gives a hemiacetal,

Addition of the second equivalent of alcohol is accompanied by loss of one molecule water to yield the produce acetal.

Aldehydes and ketones react reversibly with two equivalents of alcohol in the presence-example-1
Aldehydes and ketones react reversibly with two equivalents of alcohol in the presence-example-2
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