ABC26OR0012 · General Organic Chemistry
Subject: Organic Chemistry · Chapter: General Organic Chemistry · Topic: Nomenclature Polycyclics · Exam: CSIR-NET JUNE 2012 · Marks: 2 · Difficulty: Medium
The IUPAC name of the compound given below is: 
(a)ethyl (R)-2-methyl-4-oxocyclohex-2-enecarboxylate
(b)ethyl (S)-2-methyl-4-oxocyclohex-2-enecarboxylate
(c)(R)-4-ethoxycarbonyl-3-methylcyclo-hex-2-enone
(d)(S)-4-ethoxycarbonyl-3-methylcyclo-hex-2-enone
Answer
Answer (as printed): B
Explanation
• Ester is the main functional group of the above compound. Thus the numbering of carbon chain starts from ester carbon. Also note, in the nomenclature of the compound with multiple substituents, alphabetical order is followed while writing. Since e comes before m, ethyl is written first followed by methyl. • The configuration of the chiral centre is identified by using CIP rules.
Explanation as extracted from the printed page; notation may be imperfect.