Q. Names of some compounds are given. Which one is not correct in IUPAC system ?
A) CH₃–CH(OH)–CH(CH₃)–CH₃ : 3-methyl-2-butanol
B) CH₃–C≡C–CH(CH₃)₂ : 4-methyl-2-pentyne
C) CH₃–CH₂–C(=CH₂)–CH(CH₃)–CH₃ : 2-ethyl-3-methyl-but-1-ene
D) CH₃–CH₂–CH₂–CH(CH₂CH₃)–CH(CH₃)–CH₂CH₃ : 3-methyl-4-ethyl heptane
Explanation
[Solution from source] For CH₃CH₂CH₂–CH(C₂H₅)–CH(CH₃)–CH₂CH₃ the substituents must be cited alphabetically: 4-ethyl-3-methylheptane, so '3-methyl-4-ethyl heptane' is incorrect. The other three names correctly identify the parent chain and lowest locants. Answer (4).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.