An organic compound with molecular formula C₉H₁₀O forms 2, 4-DNP derivatives, reduces Tollen’s reagent and undergo canizaro reaction, on vigorous oxidation, it gives 1, 2-Benzene dicarboxylic acid. Structure of aromatic compound is

An organic compound with molecular formula C₉H₁₀O:

• Forms 2,4-DNP derivative, indicating presence of a carbonyl functional group.
• Reduces Tollens' reagent, confirming it is an aldehyde.
• Undergoes Cannizzaro reaction, showing it is a non-enolizable aromatic aldehyde.
• On vigorous oxidation, it yields 1,2-benzenedicarboxylic acid (phthalic acid), indicating two -COOH groups ortho to each other.

From these clues, the aromatic compound structure is:

o-Ethylbenzaldehyde (2-ethylbenzaldehyde) – a benzene ring with an ethyl group at the ortho position relative to the aldehyde.