A compound X (C8H8O) gives an orange precipitate with 2,4-DNP, gives a yellow precipitate with NaOH/I2 and does not reduce Tollens reagent. Clemmensen reduction of X gives a hydrocarbon that on vigorous oxidation gives benzoic acid. X is

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A compound X ( $C X_{8} H X_{8} O$ ) gives an orange precipitate with 2,4-DNP, gives a yellow precipitate with $NaOH / I X_{2}$ and does not reduce Tollens reagent. Clemmensen reduction of X gives a hydrocarbon that on vigorous oxidation gives benzoic acid. X is

A2-methylbenzaldehyde
B4-methylbenzaldehyde
Cacetophenone
Dphenylethanal

Answer: C

DNP indicates a carbonyl compound, the iodoform test shows

CH X_{3} CO X^{-}

, and negative Tollens excludes aldehydes. This leaves

C X_{6} H X_{5} COCH X_{3}

(DoU = 5, fits). Clemmensen gives ethylbenzene, which is oxidised to benzoic acid. The three aldehydes of the same formula would all be Tollens positive and iodoform negative.

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A compound X (CX8​HX8​O) gives an orange precipitate with 2,4-DNP, gives a yellow precipitate with NaOH/IX2​ and does not reduce Tollens reagent. Clemmensen reduction of X gives a hydrocarbon that on vigorous oxidation gives benzoic acid. X is

Answer: C

More questions on Structure determination from reaction sequences

A compound X ( $C X_{8} H X_{8} O$ ) gives an orange precipitate with 2,4-DNP, gives a yellow precipitate with $NaOH / I X_{2}$ and does not reduce Tollens reagent. Clemmensen reduction of X gives a hydrocarbon that on vigorous oxidation gives benzoic acid. X is