Question

What is the correct IUPAC name of α-Methylcyclohexanone?

(a) Methylcyclohexanone

(b) Methylcyclohexan-2-one

(c) 2-Methylcyclohexanone

(d) Cyclomethylhexan-2-one

This question was addressed to me in an interview.

The query is from Nomenclature and Structure of Carbonyl Groups in division Aldehydes, Ketones and Carboxylic Acids of Chemistry – Class 12

Answer 1

Correct answer is (c) 2-Methylcyclohexanone

For explanation I would say: Alpha represents the presence of a substituent on the carbon next to the carbon of the CO group. The ketone group is given the lower number in case of substituted ketones hence the number 2 is associated with the methyl group in this case.