A common product of esterification of a carboxylic acid with methanol under acid catalysis is what?

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Multiple Choice

A common product of esterification of a carboxylic acid with methanol under acid catalysis is what?

In acid-catalyzed esterification, a carboxylic acid reacts with an alcohol to form an ester and water. The alkoxy part of the ester comes from the alcohol used. Since the alcohol here is methanol, the product is the methyl ester of the carboxylic acid (the ester has a -OCH3 group). Mechanistically, protonation of the carbonyl makes it more electrophilic, methanol attacks, a tetrahedral intermediate forms, water leaves, and then deprotonation gives the ester. The equilibrium can be driven toward ester formation by removing water or using excess methanol. Anhydride would come from dehydration of two carboxylic acids, not from reacting with an alcohol. Ethyl ester would require ethanol as the alcohol. A ketone isn’t the product of this esterification.

In acid-catalyzed esterification, a carboxylic acid reacts with an alcohol to form an ester and water. The alkoxy part of the ester comes from the alcohol used. Since the alcohol here is methanol, the product is the methyl ester of the carboxylic acid (the ester has a -OCH3 group).

Mechanistically, protonation of the carbonyl makes it more electrophilic, methanol attacks, a tetrahedral intermediate forms, water leaves, and then deprotonation gives the ester. The equilibrium can be driven toward ester formation by removing water or using excess methanol.

Anhydride would come from dehydration of two carboxylic acids, not from reacting with an alcohol. Ethyl ester would require ethanol as the alcohol. A ketone isn’t the product of this esterification.

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