Cyclohexanone is subjected to the…

Cyclohexanone is subjected to the following transformations.

One or more options correct

Cyclohexanone is subjected to the following transformations. The correct statement(s) is/are

A. Treatment with $\mathrm{NH_2OH}$ , followed by heating of the oxime with conc. $\mathrm{H_2SO_4}$ , gives a seven-membered cyclic amide of molecular formula $\mathrm{C_6H_{11}NO}$ .
B. Reaction with $\mathrm{PhMgBr}$ followed by $\mathrm{H_3O^+}$ gives a tertiary alcohol that, on heating with conc. $\mathrm{H_2SO_4}$ , gives mainly $1$ -phenylcyclohexene.
C. Wolff-Kishner reduction ( $\mathrm{N_2H_4}$ , $\mathrm{KOH}$ , ethylene glycol, heat) gives cyclohexanol.
D. Treatment with $\mathrm{I_2}$ and $\mathrm{NaOH}$ gives a yellow precipitate of iodoform and sodium cyclohexanecarboxylate.

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Answer: A, B

(A) True. The oxime undergoes Beckmann rearrangement; the group anti to the

\mathrm{OH}

migrates to nitrogen, expanding the six-membered ring to

\varepsilon

-caprolactam,

\mathrm{C_6H_{11}NO}

. (B) True. Grignard addition gives 1-phenylcyclohexan-1-ol; acid-catalysed dehydration proceeds through a tertiary benzylic carbocation and the conjugated, more substituted alkene 1-phenylcyclohexene is the major product (Saytzeff product). (C) False. Wolff-Kishner converts

\mathrm{C{=}O}

into

\mathrm{CH_2}

, giving cyclohexane, not an alcohol. (D) False. The haloform reaction requires a

\mathrm{CH_3C{=}O}

group or a group oxidisable to it; cyclohexanone has no methyl ketone unit, and the ring would not be cleaved to give a cyclohexanecarboxylate. Correct: A and B.

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