MHTCET 16 May 2024 Shift 1 Paper

Concept:For substituted cycloalkanes, the ring is numbered to give the lowest locant set to all substituents.Explanation:The parent chain is cyclobutane.The substituents are methoxy ($-\mathrm{OCH}_3$) and two methyl groups ($-\mathrm{CH}_3$).If the carbon bearing the two methyl groups is numbered $1$, the locants become $1,1,3$ (methyls at $1,1$; methoxy at $3$).If the carbon bearing methoxy is numbered $1$, the locants become $1,3,3$.The set $1,1,3$ is lower than $1,3,3$, so this numbering is preferred.Thus, the gem-dimethyl carbon is at position $1$ and the methoxy carbon is at position $3$.Alphabetically, methoxy comes before methyl.Hence, the correct IUPAC name is $3$-methoxy-$1,1$-dimethylcyclobutane.Answer:Option B: $3$-Methoxy-$1,1$-dimethylcyclobutane.