Which of the following represents the correct IUPAC name for the compounds concerned?
(i) 2,2-dimethylpentane or 2-dimethylpentane
(ii) 2,4,7-trimethyloctane or 2,5,7-trimethyloctane
(iii) 2-choloro-4-methylpentane or 4-chloro-2-methylpentane
(iv) But -3-yn-l-ol or But-4-ol-l-yne
(i) 2,2-dimethylpentane (because for the two alkyl groups on the same carbon, its locant is repeated twice)
(ii) 2, 4, 7-trimethyloctane (because 2, 4, 7-locant set is lower than 2, 5, 7).
(iii) 2-chloro-4-methylpentane. (Alphabetical order of substituents)
(iv) But-3-yn-l-ol (because lower locant for the principal functional group, i.e., alcohol).