Q. Which nomenclature is not according to IUPAC system?
A) CH₃–CO–CH₂–CH₂–CH₂–COOH : 5-oxohexanoic acid
B) Br–CH₂–CH=CH₂ : 1-Bromo-prop-2-ene
C) CH₃–CH₂–C(Br)(CH₃)–CH₂–CH(CH₃)₂ : 4-bromo-2,4-dimethylhexane
D) (CH₃)₂CH–CH(C₆H₅)–CH₂CH₃ : 2-methylpentan-3-ylbenzene
Explanation
[Solution from source] Br–CH₂–CH=CH₂ must be numbered to give the double bond the lowest locant, so its IUPAC name is 3-bromoprop-1-ene, not 1-bromoprop-2-ene. The other names are correct: 5-oxohexanoic acid, 4-bromo-2,4-dimethylhexane (locants 2,4,4 beat 3,3,5) and (2-methylpentan-3-yl)benzene. Answer (2).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.