MHTCET 22 Apr 2025 Shift 1 Paper

Concept:The principal functional group $-\mathrm{COOH}$ decides the parent name; all other groups are written as prefixes.Explanation:The given compound contains $-\mathrm{COOH}$, $-\mathrm{CHO}$ and $-\mathrm{CH}_3$ groups attached to the benzene ring.Since $-\mathrm{COOH}$ has higher priority than $-\mathrm{CHO}$, the parent is benzoic acid and $-\mathrm{CHO}$ is named as formyl.Number the ring from the carbon bearing $-\mathrm{COOH}$.To get the lowest locants, $-\mathrm{CH}_3$ takes position 2 and $-\mathrm{CHO}$ takes position 5.Alphabetically, formyl is written before methyl.Hence the correct IUPAC name is 5-formyl-2-methylbenzoic acid.Answer:5-Formyl-2-methylbenzoic acidCorrect option: D.