An organic compound with the molecular folmula `C_(9)H_(10)O` form 2,4-DNP derivative, reduces Tollens reagent, and undergoes Cannizaro reaction. On vigorous oxidation, it gives 1,2-benzenedicarboxylic acid. Identify the compound.

Explanation

(i) Since the given compound with M.F. `C_(9)H_(10)O` forms a 2,4-DNP derivative and reduces tollens' reagent, it must an aldehyde.
(ii) Since it undergoes Cannizzaro reaction, therefore, CHO group is directly attached to the benzene ring.
(iii) Since on vigorous oxidation, it gives 1,2-benzenedicarboxylic acid, therefore, it must be an ortho-substituted benzaldehyde, the only o-substituted aromatic aldehyde having M.F. `C_(9)H_(10)O` is 2-ethylbenzaldehyde. All the reactions can now be explained on the basis of the structure.
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