Question

According to IUPAC convention, name of the following compound is:

A. 3-chloro-5-ethyl benzoate
B. ethyl-3-chloro-5-ethyl benzoate
C. meta chloro-meta methyl ethyl ethyl benzoate
D. both 'B' and 'C' are correct

Answer 1

Identify the parent compound and the substituents present. Identify the order of priority of groups for numbering the benzene ring.

Complete answer:
The option A is incorrect because it says that the alkyl part of the alcohol from which benzoate easter was obtained, contains chloro substituent which is incorrect.
The option C is incorrect because in the IUPAC system, the prefix meta is not used. Instead the carbon atoms of benzene ring are numbered. So, you can rule out both options C and D.
Draw the structure of given organic compound as shown below:

In the above compound, the parent compound is ethyl benzoate. Write the structure of parent compound as shown below:

In the parent compound, ethyl ester of benzoic acid is present.
The given compound is the derivative of ethyl benzoate with two substituents on the benzene ring, one is chlorine atom and other is ethyl group.
You can start the numbering of the benzene ring from the carbon atom bearing ester substituent and then go in the direction that gives the lowest locant to the chlorine atom.

The correct IUPAC name of the given compound is ethyl 3-chloro-5-ethyl benzoate.

**Hence, the correct option is the option B.

Note:**
Benzoic acid contains a carboxyl group linked to benzene rings. When it reacts with ethanol in presence of sulphuric acid catalyst, ethyl benzoate is obtained.