Question

The IUPAC name of

is:

• A. 2-Chlorocarbonyl ethylbenzoate
• B. Ethyl-2-(chlorocarbonyl)benzoate
• C. 2-Carboxyethyl benzoyl chloride
• D. Ethyl-1-(chlorocarbonyl)benzoate

Answer 1

Answer: (B)

Ethyl-2-(chlorocarbonyl)benzoate

Answer 2

The given structure is a benzene ring substituted with an ethyl ester group ($-\text{COOC}_2\text{H}_5$) and an acid chloride group ($-\text{COCl}$) at adjacent (ortho) positions.

According to IUPAC nomenclature rules for esters, the alkyl group attached to the oxygen atom of the ester is named first, followed by the name of the carboxylate anion. In this case, the alkyl group is ethyl, and the carboxylate part is derived from benzoic acid. Therefore, the parent ester name is ethyl benzoate.

The two substituents are at ortho positions. Let's assign position 1 to the carbon atom bearing the ethyl ester group. Then, the carbon atom bearing the acid chloride group is at position 2. The $-\text{COCl}$ group is named as a chlorocarbonyl substituent.

Combining these, the IUPAC name is Ethyl 2-(chlorocarbonyl)benzoate.