Transesterification of ethyl benzoate with methanol under acid catalysis yields which ester?

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Multiple Choice

Transesterification of ethyl benzoate with methanol under acid catalysis yields which ester?

Transesterification is the exchange of the alkoxy group of an ester with the alcohol present, under acid or base catalysis. Here, ethyl benzoate (benzoic acid ethyl ester) reacts with methanol. The acid catalyst activates the carbonyl, methanol adds to form a tetrahedral intermediate, and the ethoxy group leaves as ethanol. The carbonyl then reforms with the methoxy group, giving methyl benzoate and ethanol as a byproduct. If methanol is in excess and ethanol is removed, the equilibrium favors the methyl ester. The other options would require hydrolysis or a different substitution pattern, so the product is methyl benzoate.

Transesterification is the exchange of the alkoxy group of an ester with the alcohol present, under acid or base catalysis. Here, ethyl benzoate (benzoic acid ethyl ester) reacts with methanol. The acid catalyst activates the carbonyl, methanol adds to form a tetrahedral intermediate, and the ethoxy group leaves as ethanol. The carbonyl then reforms with the methoxy group, giving methyl benzoate and ethanol as a byproduct. If methanol is in excess and ethanol is removed, the equilibrium favors the methyl ester. The other options would require hydrolysis or a different substitution pattern, so the product is methyl benzoate.

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